Dissertations / Theses on the topic 'Animal reproduction and breeding'

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1

Taylor, Eric Clayton. "Reproductive parameters of dorper ewes during the breeding and non-breeding seasons in south Texas." Thesis, Texas A&M University - Kingsville, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1590222.

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There have been many changes in the United States sheep industry over the years. Decreasing profitability of wool production has shifted the focus of many producers to strictly meat production. In south Texas, extreme high summer temperatures add an additional challenge in raising wool breeds of sheep. Hair sheep are gaining popularity in lamb-only production systems as they are more adapted to hot climates and eliminate shearing costs. The Dorper is the most popular breed of hair sheep throughout Texas due to superior lamb carcasses. Maximizing reproductive efficiency is critical for increasing the profitability of sheep production. Accelerated lambing systems can produce 3 lamb crops every two years versus 1 lamb crop per year. For this to be accomplished, ewes must be capable of breeding early post-partum and at all times of the year. We determined the reproductive characteristics of Dorper ewes. In the absence of a ram, Dorper ewes were anestrous from March until May. We observed considerable variation of ewes when both entering and ending anestrous. During the initial breeding season, 7-d CIDR® treated ewes, which conceived 1st service, had a significantly lower mean day of birthing (3.2 ± 2.1 d) compared to (10.1 ± 1.9 d) control ewes, resulting in a shorter lambing duration. During the seasonal anestrous period both CIDR® treated and control post-partum Dorper ewes were stimulated to ovulate while in the presence of the ram. However, during this time, 9-d CIDR® treatment significantly shortened both overall ram to lambing interval (152.8 ± 3.2d vs.165.7 ± 3.0 d) and first service ram to lambing interval (149.3 ± 1.3 d vs. 160.7 ± 1.5 d). Fall-born Dorper ewes with known birth dates had a mean age of puberty of 306.5 ± 4.9 d. Fall-born yearlings and spring-born ewe lambs were exposed to a ram during the first fall breeding season following their birth. While no difference was found in overall conception rate, fall-born yearlings had a significantly greater first service conception rate (83.3 %) compared to spring-born lambs (28.6 %). The findings of this study illustrate that Dorper ewes have the potential to be utilized in accelerated lambing systems in south Texas. By achieving a high conception rate post-partum simultaneous to the anestrous season, we were able to maintain an 8 mo lambing interval during the first two breeding season. We conclude that the reproductive attributes of the Dorper ewe makes them an excellent choice for sheep producers throughout South Texas.

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Schmalz-Peixoto, Karin E. von. "Factors affecting breeding in captive Carnivora." Thesis, University of Oxford, 2003. http://ora.ox.ac.uk/objects/uuid:64687fe3-f6ca-4d9b-90d8-b6f1e565711a.

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Captive carnivores pose a challenge for conservationists and institutions alike, presenting many problems that range from diseases to poor welfare and unsuccessful breeding. Available databases of captive populations are rich sources of information that can help determine which factors can affect breeding success and the real potential of these populations in conservation programmes. Some species, such as tigers Panthera tigris, seem to preserve in captivity the same reproductive parameters seen in wild animals, making captive individuals extremely useful in the research of reproductive biology, that can be applied in evolutionary and physiological studies of the order Carnivora. Specific reproductive characteristics, mainly connected with the altriciality of the young, can make some species more prone to lose young in captivity than others, and these factors must be taken into consideration when developing ex situ conservation programmes. Infant mortality in captivity seems to be primarily caused by inadequate maternal behaviour, which can be connected to biological factors as well as to individual characteristics such as origin and rearing methods. Maternal infanticide, either passive or active, is also affected by biological and ecological characteristics of the species, and there may be an effect of the origin of the females, i.e. if they were wildcaught or captive-born. Housing conditions and individual history affect infant mortality, with females that suffered transfer between institutions exhibiting lower breeding success. Also, institutions with thriving research programmes presented higher infant mortality overall, independently of their latitude or management system, which can indicate an effect of human interference. Further research, both in the wild and in captivity, is needed to fully understand the factors affecting breeding success of captive carnivores.
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3

Real, Garcia Enric. "Influence of predictable anthropogenic food subsides on seabird´s breeding investment." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/668552.

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Recent policies on the ban of fishing discards and the closure of open-air landfills are expected to reduce amount of predictable anthropogenic food subsidies (PAFS) for seabirds. To forecast the ecological consequences of these policies, it is necessary to understand the influence that each of these resources has on ecological parameters and how this can be mediated by density-dependent mechanisms. Besides, for those species exploiting both types of resources, it is important to consider whether or not their effects act synergistically. Finally, it is also important to understand how the ecological interactions between seabirds and PAFS can be influenced by other potentially important environmental factors, such as for example, the abundance of natural prey or the one of foraging conditions. In the first chapter of this thesis, I reviewed the current knowledge on the ecological interactions between seabirds and fishery discards, with the aim of identifying the main knowledge gaps and to propose new challenges to improve our understanding of the ecological role of PAFS availability to seabirds. In the second chapter, I assessed the relative role of fishery discards and open-air landfills in the breeding investment of a generalist seabird, investigating the possible interplay with density-dependent mechanisms. In the third chapter I collaborated to investigate the role of PAFS in buffering environmental stochasticity and disrupting the natural synchronous dynamics between two seabirds. Finally, in the last chapter, I assessed the importance of several environmental factors in the breeding investment of three seabirds with contrasting life-history strategies. In particular, I considered local environmental variables (food abundance, competition and sea state) during breeding as well as the influence of winter conditions summarized by a large-scale climatic index, the North Atlantic Oscillation (NAO). Considering these variables simultaneously allowed me to assess the relative importance of natural and anthropogenic food resources, intra- and inter-specific competition and foraging conditions in the form of detectability and accessibility of food. This thesis shows that the main knowledge gaps on seabird-discard ecological interactions are related to survival, dispersal and reproduction, the resilience of their populations against perturbations and the role of individual specialization in the foraging process. Results showed that both fishery discards and open-air landfills can significantly increase seabirds’ breeding investment. However, the landfill effect was weaker than the effect of fishing discards, probably due to the lower quality of waste as food resource. It is also shown that these effects can be masked by density-dependence processes. In addition, the thesis highlights the importance of considering the possible influence of socio-economic factors on the availability of these PAFS depending on the geographic area considered. I showed that PAFS can alter natural stochasticity, increasing the breeding investment of generalist species, which in turn, may alter the community structure. Finally, this thesis makes evident that foraging conditions in the form of detectability and accessibility of food can play a very important role in key demographic parameters such as breeding investment. This implies that in contrast to what is commonly assumed, food abundance does not directly translate into food intake. Finally, the results also suggest that the influence that the winter North Atlantic Oscillation has on breeding investment in some seabirds is limited to winter months and acts in spring as a ‘carry-over’ effect of winter conditions.
Las recientes políticas en materia de prohibición de descartes y cierre de vertederos, supondrán una importante reducción de la disponibilidad de los recursos antropogénicos predecibles (PAFS) para las aves marinas. Para entender mejor las consecuencias ecológicas de esta reducción y proponer nuevos retos futuros, en esta tesis se revisa el conocimiento actual sobre las interacciones ecológicas que se dan entre las aves marinas y los descartes de la pesca. Por otra parte, también se evalúa cómo los PAFS y otros factores ambientales influyen en la inversión que las aves marinas hacen en la reproducción. Los resultados muestran que los principales vacíos de conocimiento en relación a las interacciones entre aves marinas y descartes, son los relacionados con la supervivencia, la dispersión, la reproducción, la resiliencia de las poblaciones frente a las perturbaciones y la especialización individual en el proceso de forrajeo. También se muestra que tanto los descartes de la pesca como la basura de los vertederos incrementan la inversión en la reproducción. Sin embargo, este efecto es menos marcado en los vertederos, probablemente debido a su menor calidad como recurso alimentario. También se ha observado que estos efectos pueden quedar enmascarados por procesos de densodependencia. La tesis también demuestra la importancia de considerar los factores socioeconómicos al evaluar la disponibilidad de los PAFS, dependiendo del área geográfica considerada. También se muestra que los PAFS pueden alterar la estocasticidad natural, incrementando la inversión en reproducción en especies generalistas, lo cual puede alterar la estructura de la comunidad. También se muestra cómo los factores ambientales que condicionan la detectabilidad y accesibilidad del alimento pueden jugar un papel muy importante en la inversión en la reproducción. Esto implica que el hecho de que el alimento sea abundante, no implica que esté disponible para los organismos. Finalmente, los resultados también sugieren que la influencia de la Oscilación del Atlántico Norte en la inversión en la reproducción de algunas aves marinas, se limita a los meses de invierno y se manifiesta en primavera en forma de efectos de tipo carry-over.
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Duckworth, Janine Alma. "Studies of seasonality in red deer (Cervus elaphus) : with special emphasis on the reproductive physiology of red deer hinds." Lincoln University, 1992. http://hdl.handle.net/10182/2267.

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Four trials were conducted to investigate factors controlling the seasonal onset of reproductive activity in red deer hinds. Firstly (Chapter 4), the role of photorefractoriness to long daily photoperiods in the initiation of the seasonal reproductive activity in breeding red deer hinds was examined. Red deer hinds (n=10) were prematurely exposed to a long daily photoperiod of 15.3 h from 22 July to 8 November 1986 i.e. winter-spring (EPW), or maintained under natural photoperiods (NP). Six hinds experienced the natural changes in daily photoperiod until mid-summer but were exposed to a 15.5 h of light each day from 30 January to 30 April 1987, i.e. summer-autumn (EPS), whilst hinds in the other groups experienced naturally decreasing daily photoperiods. On 5 occasions (July 1986, January, February, March and April 1987), blood samples were collected from 4 NP and 4 EPW hinds every 20 minutes for 4 h to monitor secretion of luteinising hormone and half hourly for another 4 h following an i.v. injection of 2 µg GnRH to measure pituitary responsiveness. In January, March and April 1987 EPS hinds were also intensively sampled for 4 h. Plasma progesterone concentrations and mean date of calving indicated that the onset of breeding activity was not affected by light treatment in the EPW hinds but was delayed by 3 weeks in the EPS hinds. In contrast, supplementary lighting caused a premature elevation of plasma prolactin concentrations and advanced pelage moulting in EPW hinds only. Plasma LH secretion patterns indicated that LH pulse frequency and mean LH concentrations were greater during the breeding season than during pregnancy or, seasonal or postpartum, anoestrus. The reduction in LH secretion was partially explained by a diminished pituitary responsiveness to GnRH. Daily plasma melatonin secretion patterns indicated that the duration of the nocturnal increase in melatonin concentrations was responsive to changes in photoperiod and provided a suitable endocrine signal for measuring day length. The results suggest that, unlike the sheep and prepubertal red deer hind, the onset of seasonal breeding activity in breeding red deer hinds is not affected by long daily photoperiods in spring but is delayed if the autumnal decrease in daily photoperiod is delayed. Therefore neither the development of photorefractoriness nor the spring increase in daily photoperiods initiated the transition from seasonal anoestrus to reproductive activity in the breeding hind. However, long daily photoperiods may have entrained the annual cycle of pelage shedding and prolactin secretion. It is possible that the neuroendocrine pathway by which photoperiodic signals entrain the seasonal cycle of reproduction is separate from those which regulate other seasonal events in the breeding red deer hind. Secondly (Chapter 5), in a study of seasonality of reproduction, 4 pubertal hinds were monitored for live weight and plasma LH and progesterone concentrations from December 1987 to October 1988 (i.e. 12-22 months of age). In addition the pattern of LH secretion was also studied in 4 ovariectomised pubertal hinds implanted s.c. with controlled release implants containing 12 mg oestradiol-17β between 4 March and 25 May and between 15 June and 19 September, 1988. On several occasions (15 December, 29 February, 15 March, 24 April, 14 June, 29 June, 18 September (all hinds) and 3 October (ovariectomised hinds only) blood samples were collected every 20 minutes for 4 h to monitor secretion of luteinising hormone and following an i.v. injection of 2 µg GnRH to measure pituitary responsiveness. Plasma progesterone profiles indicated that 4-6 ovarian cycles, lasting about 19 d each, occurred in each intact hind. Regular ovarian cycles commenced in late April (26 April ± 3.4 d, mean ± s.e.m.) and ceased 3 months later in July (21 July ± 7.2 d). The number of LH pulses in the intact hinds was higher in June (1-2 pulses/4 h) than in the non-breeding season (< 1 pulse/4 h) probably due to a seasonal increase in GnRH secretion. It appears that the seasonal increase in LH pulsatility and onset of reproductive activity in the entire hinds were temporally related to a reduction in the sensitivity of LH secretion to the negative feedback effects of oestradiol in ovariectomised pubertal hinds. In the third trial (Chapter 6), 20 male and 20 female red deer calves were immunised at birth against a melatonin conjugate or injected with adjuvant only (controls). Booster injections were given on 5 occasions over the next 2 years. Stags which produced significant melatonin binding activity in response to immunisation, were heavier than the controls between 7 and 11 months of age and at 16, 20, 30 and 34 months of age. A similar but smaller effect on live weight was seen in the immunised hinds. Immunisation against melatonin did not affect the calving date of the hinds or antler development and time of casting of antlers in the stags. These results indicated that disruption of the photoperiodic signal by immunisation against melatonin may have prevented the entrainment of annual rhythms in feed intake and growth but without affecting the seasonal cycles in antler growth and ovarian activity. Finally in a series of 3 trials (Chapter 7), anoestrous red deer hinds were induced to ovulate with the GnRH analogue, buserelin. Hinds were pre-treated with intravaginal devices containing 0.6 g progesterone (CIDR-Type S) for 14 days prior to CIDR withdrawal on 4 March. In Year 1, 15 hinds were treated with 1 CIDR each and 8 hinds were injected i.m. with 4 µg buserelin (a GnRH analogue) at CIDR removal followed by 2nd injection of 10 µg 48 h later. In Year 2, 16 hinds were treated with 2 CIDRs each and 8 hinds were injected Lm. with 4, 3, 2, 2 and 10 µg buserelin at -48, -24, 0, 24 and 48 h respectively from CIDR withdrawal. In Year 3, 15 hinds were treated with 2 CIDRs and 11 hinds (Groups Band BO) injected with buserelin identical to the protocol in Year 2. At CIDR withdrawal 6 of these buserelin treated hinds (Group BO) and 4 other progesterone-primed hinds (Group 0) were injected with 500 µg oestradiol benzoate. In addition, during the breeding season, 4 hinds (Group C) were treated with double CIDRs only for 14 d from 1 April. When oestrous behaviour and the pattern of plasma LH secretion were monitored in Year 3, oestrous behaviour was less noticeable and delayed in Group B hinds and peak LH levels were lower and increased later relative to Group 0, BO and C hinds. Two weeks after CIDR withdrawal, 6 buserelin-treated hinds in both Year 1 and Year 2, and 3/5 B, 2/4 0, 3/6 BO and 4/4 C group hinds in Year 3 had a single corpus luteum present. Plasma progesterone concentrations were elevated for about 12 d in most hinds with a corpus luteum in Year 2 and in most B, BO and C Group hinds in Year 3. However, progesterone secretion was low in several Year 1 and all Group 0 hinds in Year 3 indicating that the induced corpora lutea in these hinds were functionally subnormal. There was no evidence that any of the buserelin-induced ovulations resulted in pregnancy, probably because the induced ovulations were not accompanied by normal hormonal and behavioural patterns. The experiments described in this thesis have contributed to our understanding of the regulation of seasonal breeding in red deer hinds. This knowledge may eventually enable reproductive activity to be effectively manipulated, thereby improving the efficiency of deer production systems.
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Mercadante, Maria Eugênia Zerlotti. "Análise de um experimento de seleção para crescimento em bovinos nelore: respostas direta no peso ao sobreano e correlacionadas no tamanho e reprodução das matrizes." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-12052003-135023/.

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Foram estudados dados provenientes do experimento de seleção estabelecido na Estação Experimental de Zootecnia de Sertãozinho (IZ - SP), com o objetivo de avaliar a resposta direta no peso ao sobreano de machos e fêmeas e as respostas correlacionadas no tamanho e caracteres reprodutivos das matrizes. O experimento iniciou em 1978, com três rebanhos da raça Nelore, seleção (NeS), tradicional (NeT) e controle (NeC), sendo os dois primeiros selecionados para maior peso ao sobreano e o terceiro para a média deste peso. O NeT diferencia-se de NeS por ter recebido, eventualmente, touros de outros rebanhos, inclusive comerciais. Registros de dias ao parto foram analisados separadamente nas novilhas, vacas e vacas e novilhas sem incluir e incluindo as fêmeas não paridas. Nenhuma diferença significativa (P<0,05) foi detectada entre os desempenhos das fêmeas dos rebanhos selecionados (NeS e NeT) e as do controle (NeC). As herdabilidades variaram de 0,02 a 0,16, sendo as mais altas obtidas em arquivos nos quais foram incluídos os registros das fêmeas não paridas. Os registros repetidos de dias ao parto de vacas e novilhas incluindo as fêmeas não paridas foram também analisados por modelo de regressão aleatória com polinômios ortogonais (Legendre) da idade na monta (em anos) como a covariável independente, para avaliar este caracter longitudinalmente durante a vida produtiva das fêmeas. As herdabilidades estimadas aumentaram de 0,08 a 0,28 da 1 a à 6 a monta. A seleção para peso não alterou o valor genético médio das vacas de NeS e NeT, entretanto os valores genéticos das vacas do NeC mostraram tendência de queda no decorrer dos anos, além de longitudinalmente, com o avanço da idade. Registros de peso ao sobreano dos animais nascidos de 1978 a 1998, e da altura na garupa ao sobreano das fêmeas nascidas a partir de 1985 foram analisados por modelo animal para obter a tendência genética de 1981 a 1996. Médias de peso, altura e escore de condição corporal na entrada da monta, dias ao parto e sucesso ao parto das matrizes nascidas nos últimos 4 anos foram contrastadas entre os selecionados e o NeC, em análise de quadrados mínimos. As tendências genéticas médias obtidas em 16 anos foram 1,7±0,2; 2,3±0,2 e –0,1±0,1 kg/ano nos machos e 1,9±0,2; 2,4±0,2 e –0,1±0,1 kg/ano nas fêmeas para peso, e 0,25±0,03; 0,24±0,04 e –0,04±0,03 cm nas fêmeas para altura ao sobreano, respectivamente em NeS, NeT e NeC. Novilhas e vacas de NeS e NeT foram 19% e 15% mais pesadas e 4% mais altas na entrada da monta, em relação às do NeC. Não foram detectadas diferenças significativas (P<0,05) no desempenho reprodutivo das matrizes selecionadas em relação ao NeC. Os resultados indicaram que a seleção para peso corporal promoveu respostas altas e consistentes nos pesos e alturas ao sobreano e em idades mais tardias, sem comprometer o desempenho reprodutivo das matrizes.
Data from a selection experiment, carried out AT Experimental Station of Sertãozinho, State of São Paulo, Brazil, were analyzed in order to evaluate the direct response of yearling weight and the correlated responses of the size and reproduction traits of cows. The experiment started in 1978, with three lines of Nelore cattle, selection (NeS), traditional (NeT), both selected for greater yearling weight, and control (NeC), selected for mean yearling weight. The NeT line is different from the NeS one because sires from another herds were eventually introduced into the NeT line. Records of days to calving were analyzed separately for heifers, cows and cows and heifers with and without non-calver females. There were no significant differences (P<0.05) between the performance of females from the selection lines (NeS and NeT) and those from the control line (NeC). The heritabilities were between 0.02 and 0.06, and the higher estimates were from data sets including non-calver females. The repeated records of days to calving of cows and heifers with non-calvers, were too analyzed using a random regression model, with orthogonal polynomials (Legendre) of age in the breeding season (in years) as the independent covariable, to order to evaluate this trait longitudinally during the herd life of the females. The estimates of heritability increased from 0.08 to 0.28, from first up to 6 th breeding season. The selection for weight did not alter the average breeding value of cows from NeS and NeT, although the average genetic breeding values of cows declined throughout the years, and too longitudinally, with advancing age. Yearling weight of the animals born from 1978 to 1998, and the yearling hip height of females born from 1985 to 1998, were evaluated using an animal model, in order to obtain the genetic trends for the years 1981 to 1996. The averages for weight, height and body condition score at the start of the breeding season, days to calving and calving success of cows born in the last 4 years, were contrasted between the selected (NeS and NeT) and control lines. The genetic trends obtained after 16 years were 1.7±0.2; 2.3±0.2 and –0.1±0.1 kg/year for males and 1.9±0.2; 2.4±0.2 e –0.1±0.1 kg/year for females with respect to weight, and 0.25±0.03; 0.24±0.04 and –0.04±0.03 cm for females with respect to yearling height for the NeS, NeT and NeC lines, respectively. Heifers and cows from NeS and NeT were 19% and 15% heavier and 4% taller at the start of the breeding season than those from NeC. Significant differences (P<0.05) were not detected with respect to the reproductive performance between selected (NeS and NeT) and control females. The results indicated that the selection according to body weight gave high and consistent responses for weight and height both at the yearling and later ages, without compromised the reproductive performance of the cows.
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Krebs, Elizabeth Ann. "Reproduction in the cattle egret (Bubulcus ibis ibis) : the function of breeding plumes." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60507.

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This study investigates the colonization of Barbados, the seasonality of breeding, and the function of breeding plumes in the cattle egret Bubulcus ibis ibis. Colonization occurred around 1956, and the island now has 4 colonies. Numbers of birds at each colony are still increasing. Colonies are evenly spaced around the island. Plumage scores varied seasonally, and males had higher scores than females. Breeding activity peaked in July-August and November-March. Conspecific interference may force poorly plumed birds to breed when environmental conditions are poor. Chick mortality was primarily from starvation during periods of low breeding activity, and primarily from conspecific attack during high breeding activity. Fledging success did not increase with breeding activity. Plumage scores correlated positively in breeding pairs. Well-plumed males fed chicks more often than poorly plumed males and had the higher fledging success. Males contributed more to nest and nestling attendance when their mates were well plumed. Plumes appear to indicate the potential paternal care and the genetic quality of a mate.
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McLaren, Elizabeth B. 1962. "Clutch size in pigeon guillemots : an experimental manipulation and reproductive success in one and two egg clutches." Thesis, Thesis (M.S.)--University of Oregon, 1991, 1991. http://hdl.handle.net/1794/9928.

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Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 63-68). Description: viii, 68 leaves : map ; 29 cm.
The ability of the Pigeon Guillemot Cepphus columba to rear an additional chick was tested by manipulating clutch sizes. The effect of the manipulations on growth, and hatching, fledging, and egg success was measured in chicks from experimental, natural, and control nests. No significant differences were observed between the nest types. Data from 1983, 1984, 1985, and 1989 were analyzed for potential differences in reproductive success of one and two egg clutches. The ratio of one to two eggs was significantly higher in 1985 and 1989. Hatching and fledging success was significantly higher for two egg clutches in 1985 and 1989. No significant differences were observed for egg success. Egg volume was significantly greater in two egg clutches in 1983 and 1984. Egg volume was correlated with fledging but not with hatching success.
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Persson, Ylva. "Breeding soundness evaluation of young beef bulls /." Uppsala : Dept. of Clinical Sciences, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200718.pdf.

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Vergamini, Marie. "Managing Sociality of a Captive Female Bornean Orangutan from Breeding to Post-partum at The Smithsonian's National Zoo." VCU Scholars Compass, 2017. https://scholarscompass.vcu.edu/etd/5161.

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The Association of Zoos and Aquariums’ Orangutan Species Survival Plan® aims to maintain 100 Bornean orangutans (Pongo pygmaeus) in captivity. Because investment in breeding these lineages is high, properly managing sociality of potential mothers is essential. This study assessed how behaviors of a captive breeding female at the Smithsonian’s National Zoo changed from pre-gestation through the offspring’s sixth month of age to improve breeding recommendations. The infant Bornean orangutan was born September 2016. Results indicate that during breeding, the mother socialized most with two adult females. During pregnancy, the pregnant female socialized in less energy-consuming ways, i.e. grooming. Post-partum socialization and proximity data suggest a shift in female affiliation. The presence of another female with maternal experience may be beneficial to the rearing of new offspring. These results can help guide socialization management for pregnant captive orangutans to improve breeding outcomes.
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Peixoto, José Eduardo. "Aspectos comportamentais da Perdiz (Rhynchotus rufescens) em cativeiro durante a fase reprodutiva: um estudo de caso." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-02042003-163413/.

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A espécie Rhynchotus rufescens, ave nativa do Brasil, denominada popularmente perdiz ou perdigão tem mostrado facilidade de adaptação ao cativeiro, e um ótimo potencial para ser explorada zootecnicamente, com a possibilidade da utilização de sua carne como fonte alternativa de proteínas, já que a carne de animais silvestres é uma alternativa alimentar em muitos países, inclusive nos desenvolvidos. A criação de perdizes de maneira racional poderia aumentar as opções da avicultura brasileira e a produção alternativa de proteína animal. O presente trabalho, identificou ritmos diários de atividades da perdiz e seu esquema de alocação temporal em uma situação de cativeiro. O conhecimento destes dados é de fundamental importância para o manejo alimentar e reprodutivo destes animais. Os dados coletados de cada lote foram feitos através de filmagem durante 12 horas ininterruptas, do amanhecer ao entardecer, por três dias consecutivos, totalizando 36 horas de filmagens. O material resultante das filmagens foi observado para obtenção da série de dados utilizados para as análises temporais, utilizando-se o sistema de amostragem temporal (time sampling) para a observação dos comportamentos das aves. Neste trabalho, determinou-se alguns padrões comportamentais de perdizes (Rhynchotus rufescens), nas condições propostas. Os ritmos associados às atividades e sua distribuição temporal foram quantificados e avaliados. Mostrou-se como a organização estrutural dos comportamentos ocorrem. Questões mais complexas como a distribuição espacial, o uso do espaço físico e social, com suas interações agonísticas e de dominância foram abordadas, e indicaram problemas de bem estar, provavelmente comprometendo a eficiência reprodutiva destes animais no cativeiro. Trabalhos futuros deverão estar atentos a estas questões. A investigação de um sistema de acasalamento eficaz é considerado fundamental para obter-se sucesso na criação desta espécie, e então partirmos para sua seleção, lembrando contudo, de estabelecer limites para esta, baseados em índices comportamentais da espécie, a fim de não incorrer-se nos erros que agora são nítidos com relação às aves especializadas para corte e postura.
The species Rhynchotus rufescens, a native bird of Brazil, popularly denominated partridge or pellet, has been showing easy adaptation to captivity and a great potential to be explored zootechnically, with the possibility of the use of its meat as an alternative source of proteins, since the meat of wild animals is a nourishment alternative in many countries, including developed ones. The breeding of partridges in a rational way could increase the options of Brazilian avilculture and the alternative production of animal protein. The present work identified the daily rhythms of activities of the partridge and its scheme of temporary allocation in a situation of captivity. The knowledge of these data is of fundamental importance for the alimentary and reproductive handling of these animals. Data related to each lot were collected through twelve uninterrupted hours of filming, from dawn to dusk, for three consecutive days, totalizing thirty-six hours of work. The material resultant from the filmings was observed in order to obtain the series of data used for the temporary analyses, having the system of temporary sampling (time sampling) been used for the observation of the behaviour of the birds. In this work, it was determined some standard behaviour of partridges (Rhynchotus rufescens), under the proposed conditions. The rhythms associated with the activities and their temporary distribution were quantified and appraised. It was shown how the structural organization of their behaviour take place. More complex subjects as space distribution, the use of physical and social space, with its agonistic and dominance interactions were approached, and they indicated problems of well being which probably interfered in the reproductive efficiency of these animals in captivity. Future works should be aware of and pay attention to these subjects. The investigation of a system of effective copulation is considered fundamental to obtain success in the breeding of this species, leading, then, to its consequent selection. Nevertheless, it is essential that limits based on behavioural indexes of the species be established, which will avoid incurring in the mistakes that are now clear in relation to specialized birds for slaughter and posture.
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11

Ash, Hayley. "Assessing the welfare of laboratory-housed marmosets (Callithrix jacchus) : effects of breeding and infant rearing background." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/21794.

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The common marmoset is the most frequently used New World primate in laboratory research and testing. In the UK, their use is strictly controlled by the Animals (Scientific Procedures) Act, which is underpinned by the principles of humane science: Replacement, Reduction and Refinement. Despite their use, there are a number of problems associated with the breeding of marmosets, including low dam longevity and increasing litter sizes. Large litters have led to high infant mortality and the need for human intervention to improve infant survival, which involves removal from the family for substantial periods of time. Previous research in a range of primate species shows that early life family separation is associated with numerous adverse behavioural and physiological effects. This project therefore sought to systematically investigate the effects of breeding and infant rearing practices, integrating a number of measures to assess the welfare of laboratory- housed marmosets. Potential predictors of dam longevity and litter size were first identified in three captive UK colonies, over four decades. Dam longevity was found to be approximately 6 years, with heavier dams living longer, but overall there was no consistent improvement in longevity over the decades. As longevity varied widely between colonies and over time, environment may be one of the most important factors. Approximately half of all births at each colony were litters larger than two, and these larger litters had greater infant mortality. Only dam weight at conception was useful in predicting litter size, with heavier dams producing larger litters. The consequences of large litters and early separation from the family for supplementary feeding were then investigated. Although twins had lower body weight than 2stays (two infants remaining with the family after death of the other littermate/s) and supplementary fed triplets, they also had the fewest health problems. There was also some evidence that animals from larger litters were more at risk of suffering from extreme low weight. Some minor differences were found in behavioural development between litter sizes. Singleton infants received more rejective rearing, while 2stays received more protective rearing, perhaps following the loss of an infant. While twin infants gained independence earlier than singletons or 2stays, they did not appear to cope better with stress in adulthood, displaying more significant increases in stress-related behaviour following the routine stressor of capture and weighing, compared to 2stays and supplementary fed triplets. While overall cortisol unexpectedly decreased from baseline to post capture, there were only significant fluctuations in 2stay marmosets. Instead, there were some increases in positive behaviour in supplementary fed triplets following the stressor, suggesting enhanced coping ability. However, in another group of supplementary fed triplets, there were subtle increases in depressive-like symptoms, measured using cognitive bias and preference tests, suggesting a reduced expectation of and interest in rewards. There were however no differences between family-reared and supplementary fed marmosets in time to learn a visual discrimination task, or in responses to temperament tests. Therefore, while it was hypothesised that early family separation would have adverse developmental consequences, there were actually very little differences between marmosets of different litter sizes and rearing backgrounds, across the range of measures. Results suggest that the current supplementary feeding programme, along with a regular human socialisation programme, minimises any potential negative effects. However, we should always be finding ways to improve the lives of animals in our care. Possible Refinements include reducing dam weight to increase twin births and improve infant survival, and training to allow supplementary feeding on the carrier’s back, to prevent infant separation and reduce disruption to the family. These Refinements could reduce fear and allow monkeys to become more resilient to the laboratory environment.
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12

Nyström, Per-Erik. "Quantitative trait loci in pig production /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5712-2.pdf.

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13

Anderson, Greg Muir. "Role of thyroid hormones in the neuroendocrine control of seasonal reproduction in red deer hinds." Lincoln University, 1997. http://hdl.handle.net/10182/2139.

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A series of eight experiments was conducted to investigate the requirement for thyroid hormones in neuroendocrine processes which lead to the seasonally anoestrous state in red deer hinds. The first two experiments used thyroidectomized, ovariectomized, oestradiol-treated hinds which received various thyroid hormone replacement treatments (n=5 per group) to investigate the timing and dose-responsiveness of thyroid hormones in bringing about seasonal oestradiol-induced suppression of plasma LH concentration. A significant seasonal decline in mean plasma LH concentration during September (coinciding with the onset of anoestrus in entire cycling hinds in New Zealand) was observed in all thyroidectomized hinds in both experiments regardless of T₄ or T₃ treatment. When oestradiol implants were removed in November or December, mean plasma LH concentrations increased significantly in all but one of hinds in which T₄ had been administered at very low doses by subcutaneous implants, and mean plasma LH concentrations and LH pulse amplitude increased in approximately half of hinds administered T₃ at varying doses by subcutaneous injections over a one-week period in October. These results suggested that thyroid hormones are not required for steroid-dependent reproductive suppression, but could possibly play a role in steroid-independent suppression of LH secretion. Because problems were encountered in delivering appropriate doses of thyroid hormones in both experiments, further confirmation of these findings was required. Therefore in the next experiment the role of thyroid gland secretions was examined in euthyroid (n=5) and thyroidectomized (n=4) ovariectomized hinds treated with oestradiol implants. These implants were removed for about one month on three occasions to examine the effect of thyroidectomy on steroid-independent control of seasonal LH secretion. During the non-breeding season basal and GnRH-induced plasma LH concentrations declined in all hinds in the presence of oestradiol, but returned to breeding season levels when oestradiol was withdrawn in November. In a concurrent experiment, thyroidectomy of ovary-entire hinds (n=7) during the breeding season prevented the cessation of oestrous cyclicity in spring; this was in contrast to oestrous cyclicity in T₄replaced (n=4) or euthyroid control (n=5) hinds which ceased to occur in early September. Collectively, these results indicate that thyroid hormones are required for the termination of the breeding season in cycling red deer hinds and that this action occurs via steroid-independent neuroendocrine pathways. Two experiments were conducted using neurotransmitter receptor agonists and antagonists to identify neural pathways in the brain which mediate LH suppression by oestradiol and by steroid-independent mechanisms, and to test if the thyroid gland is required for activation of these pathways during the non-breeding season. It was concluded from the lack of plasma LH responses to dopaminergic and opioidergic agonists and antagonists in ovariectomized and ovariectomized, thyroidectomized hinds (n=5) that neural pathways involving dopamine-D₂receptors do not mediate oestradiol-induced seasonal suppression of plasma LH concentrations, and neither dopaminergic or opioid neural pathways mediate non-steroidal suppression of plasma LH concentrations. However preliminary evidence was obtained for a stimulatory role of serotonergic neural pathways in controlling LH secretion. Another experiment was conducted to identify when the steroid-independent mechanisms which suppress LH concentrations during the non-breeding season are responsive to thyroid hormones. T₄treatment at the beginning of or during the non breeding season was effective in bringing about suppression of plasma LH concentration in thyroidectomized, ovariectomized hinds (n=5 per group), but this action of thyroid hormones did not occur during the breeding season. These results show that the steroid-independent mechanisms which contribute to seasonal suppression of plasma gonadotrophin concentrations require thyroid hormones to be present only from around the time of the end of the breeding season for their normal expression, and they remain responsive to thyroid hormones after this period. Lastly, the feasibility of achieving out-of-season breeding using thyroidectomized hinds (n=9) was evaluated by comparing oestrous behaviour, ovulation and pregnancy rates to those of euthyroid control hinds (n=7) following synchronization of oestrous cycles. There was a non-significant trend for a greater occurrence of oestrous behaviour and ovulation in thyroidectomized hinds compared with euthyroid controls during the non-breeding season, but the pregnancy rate following out-of season mating with a thyroidectomized stag was low, suggesting that a side effect of thyroidectomy may be impaired fertility. Six out-of-season pregnancies were obtained from eight matings, however because three of these pregnancies occurred in euthyroid control hinds no improvement in out-of-season reproductive performance could be attributed to thyroidectomy. It is likely that if the actions of the thyroid glands are to be exploited as a tool for achieving out-of-season breeding in this species, techniques will have to be developed for specifically blocking or overcoming the effects of thyroid hormones on the reproductive neuroendocrine centres without causing general hypothyroidism and its associated side-effects.
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14

Martin, Meghan S. "The Role of Mate Preference and Personality on Reproductive Performance in an Ex-Situ Conservation Breeding Program for the Giant Panda (Ailuropoda melanoleuca)." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/2096.

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Successful captive-breeding and re-introduction programs must have the ability to breed a surplus of genetically suitable animals for release into the wild. Unfortunately, many individuals in captive breeding programs often do not reproduce even when they are apparently healthy and presented with genetically appropriate mates. Mate choice can affect multiple parameters of reproductive sperformance, including mating success, offspring production, survival, and fecundity. We investigated the role of mate preference and personality on the reproductive performance of male and female giant pandas (Ailuropoda melanoleuca) as measured by intromission success and litter production. We conducted these studies on giant pandas at the China Conservation and Research Center for the Giant Panda (Bifengxia, Sichuan, China.) from February-May 2011, 2012, and 2013. In Chapter 2, we compared reproductive performance between individuals mated with preferred and nonpreferred males of the focal female (female preference), the focal male (male preference), and mutual mate choice perspective. There were four types of reproductive pairings in our mutual mate choice analyses: females and males that preferred each other (P-P), females that preferred the male but the male did not prefer the female (P-NP), females that did not prefer the male but the male preferred the female (NP-P), and females and males that did not prefer each other (NP-NP). Pairing giant pandas with a preferred partner increased the probability of intromission success and producing a cub. Of the 25 females mated to a preferred partner, 72% had successful intromission, 64% produced cubs, and 52% reared their own cubs versus 31%, 12%, 12% for females mated to their nonpreferred partner (N = 16). Male giant panda mate preference showed similar results. Of the 24 males that were mated with their preferred females, 75% had successful intromission, 77.8% produced cubs, and 92.9% produced cubs that were maternally reared versus 31%, 60%, 66.7% for males mated with their nonpreferred females (N = 16). There was a statistically significant difference in intromission success and cub production for P-P pairings versus NP-NP pairings. Of the twelve P-P mate dyads 83% had successful intromission, 90% produced cubs, and 88.9% had mothers rear their cubs. Of the four P-NP mate dyads 50% had successful intromission, 50% produced cubs, and 100% had the mother rear their cub. Of the seven NP-P mate dyads 57% had successful intromission, 50% produced cubs, and 100% had the mothers rear their cubs. Of the three NP-NP mate dyads 0% had successful intromission resulting in 0% producing cubs and having mother-rear cubs. In addition, we took into account various life and breeding history factors that may have affected reproductive performance such as birth location, rearing, previous sexual history with the opposite sex and familiarity status directly prior to breeding. Mate pairings that were familiar with each other as measured by successfully producing a cub in the past, had increased intromission success. Females mated to heavier males had more intromissions and produced more cubs than females mated to smaller males. In Chapter 3 and 4, we investigated the effect of personality on reproductive performance measurements. Recently, personality of individual animals has been implicated in the failure or success of captive management and breeding of threatened and endangered species. Measurements of personality included novel object tests (where behaviors of individual giant pandas were scored toward a novel object for one hour) and keeper surveys (where the primary keeper rated giant pandas on 23 adjectives describing personality); both measures significantly correlated with variation in long-term and specific mating dyad reproductive performance. In Chapter 3 we evaluated the effect of personality on long-term reproductive performance. Our results show that for both male and female giant pandas, `fearful' individuals had lower natural mating success and cub production. In addition, `aggressive' female giant pandas had increased natural mating success but decreased cub production. Males did not show these relationships between `aggressive' personality types and reproductive performance. Female giant pandas that were labeled as `aggressive' had higher frequencies of positive mating behaviors but `fearful of conspecifics' females had lower frequencies. Males labeled `fearful of conspecifics' and with high `playful-clever' component scores had a lower frequency of positive mating behaviors. In Chapter 4 we further investigated the effects of personality within a specific mating dyad. Recent studies suggest that mate compatibility within personality types can improve reproductive performance measurements such as mating success, offspring survivorship, and offspring quality. We investigated the effect of personality compatibility on reproductive performance through analyzing mate dyad similarity in personality (similar versus dissimilar), specific personality combinations, and relative personality scores (male scores higher or lower than female scores). The specific personality combinations were: females and males that were both low on the personality component (L_L), females were low but males were high (L_H), females were high but males were low (H_L), and females and males were both high (H_H). Our results suggest that giant pandas appear to be assortatively mating based on aggressive, fearful, and stereotypical-excitable personality traits. Mate dyads that were dissimilar on the stereotypical-excitable component score were more likely to have successful intromission than pairs that were similar. L_H mate dyads on the aggressive and stereotypical-excitable personality traits had increased intromission success and cub production than all other possible personality combinations. L_L on fearfulness had higher intromission success but not higher cub production than all other possible personality combinations. Mate dyads composed of males ranked high on the aggressive component relative to the female resulted in higher reproductive performance and cub production. In captive breeding programs, mates are traditionally selected solely on the basis of genetic parameters to minimize loss of genetic diversity and inbreeding coefficients. Our results suggest that integrating genetic with behavioral measures of preference, breeding history factors, and personality would increase the reproductive output of the giant panda captive-breeding program. We stress the importance of considering husbandry practices to accommodate personality traits and ultimately increase reproductive performance in the captive population while simultaneously maintaining both genetic and behavioral diversity.
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15

Holm, Dietmar Erik. "The economic effects of an oestrus synchronisation protocol using prostaglandin and reproductive tract scoring in beef heifers in South Africa." Electronic thesis, 2006. http://upetd.up.ac.za/thesis/available/etd-05042007-162414/.

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16

Gates, Peter J. "Analyzing categorical traits in domestic animal data collected in the field /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5473-5.pdf.

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17

Gocek, Cagri. "Breeding Success And Reproductive Behavior In A White Stork ( Ciconia Ciconia) Colony In Ankara." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607791/index.pdf.

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White Stork ( Ciconia ciconia, Linnaeus, 1758) is a summer visitor and passage migrant in Turkey. Although being widespread in summer near wetlands of Turkey, except for the eastern and western parts of the Black Sea Region, there has been no research on this species involving regular monitoring of nests. In this study, breeding success and survival of nestlings in a population in Kizilcahamam-Ankara as well as behavioral differences among nests and their probable consequences on breeding success were studied. Regular field observations throughout six-month long breeding seasons between 2003 and 2006 were carried out to determine parent and young behavior patterns at nest. Clutch size, and numbers of chicks hatched and fledged fluctuated throughout 2003-2006 for pairs that bred while fledgling success (average fledgling per successful nests with egg laid) were 2.63 in 2003, 3.82 in 2004, 1.89 in 2005 and 3.13 in 2006. These values are in good agreement with those recorded in northern Europe. The relationship between beginning date of incubation and both clutch size and brood size were found to be different for 2004 and 2005. Such a relationship may be significant in breeding seasons colder than usual. For 2004 and 2005, the amount of food brought and caring towards young by parents were compared with breeding success (proportion of hatched young that were fledged), and breeding success was found to increase with increasing amount of food provisioning. However, this result may be suggested to be related with weather conditions. In conclusion, Kizilcahamam White Stork population has been found to be not restricted by food or nest site availability and with a reproductive output above the European average, although annual climatic stochasticity was found to affect reproductive output.
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18

Chan, Tin-Yam. "The role of male competition and female choice in the mating success of a Lek-breeding Southern African Cichlid fish Pseudocrenilabrus Philander (Pisces: Cichlidae)." Thesis, Rhodes University, 1988. http://hdl.handle.net/10962/d1002049.

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A lek-breeding cichlid fish Pseudocrenilabrus philander was studied experimentally. Females in choice-chamber experiments showed no active choice for male size and colour, or for other male attributes, but preferred males which courted most actively. In a laboratory lek, the significant determinants of the strongly skewed mating success in males were territory size, side-shake and female chasing frequency. Together these three variables explained 79% of the variation in male mating success, with territory size alone accounting for 75% of the variation and the other two variables each accounting for 2% of the remaining variation. As there was no difference in territory quality in the laboratory lek, territory size became the principal measure of the effect of male-male competition since it was directly related to dominance. Both side-shake and female chasing could be identified as the basic factors influencing female choice, as they had an immediate effect on the display-response mating system of females. Thus, the relative importance of these three variables indicated that sexual selection in this particular lek mating species operated chiefly through the agency of intrasexual competition for dominance. However, both female behaviour and their requirement for a prolonged pre-spawning courtship had the effect of promoting male rivalry and favouring mating with dominant males. Although the intense male competition excluded subordinate males from practising normal courtship behaviour, competitively inferior males might "make the best of a bad situation" by facultatively adopting an alternative sneaking tactic to gain access to females. Spawning intrusions by females to steal freshly-laid eggs also occurred frequently. However, territorial males appeared to be relatively more tolerant of female intruders than male sneakers. Interference during spawning could lead to a longer pre-spawning courtship and even multiple-mating by females. The results of the present study and the behavioural evidence shown by males and females did not support the ʺrunaway selection modelʺ of the mating pattern in terms of sexual selection in leks, but conformed to the rival ʺwar propaganda modelʺ
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19

Kluska, Sabrina. "Análise de características reprodutivas, tratadas como variáveis categóricas, em bovinos da raça Nelore." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2477.

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O presente trabalho teve como objetivo estimar parâmetros genéticos, em uma população de bovinos da raça Nelore, para as características probabilidade de parto até os 39 meses de idade (PC39), probabilidade de permanência no rebanho (stayability), considerando três partos até 5,2 (STAY5,2) e três partos até 6,2 anos (STAY6,2), e os quatro primeiros intervalos entre partos (IEP1, IEP2, IEP3 e IEP4), tratando- as como variáveis categóricas, e para os perímetros escrotais à desmama (PED) e ao sobreano (PES), tratando-as como variáveis contínuas. Foram usados procedimentos bayesianos, em análises unicaracterística e bicaracterística, por meio dos programas THRGIBBS1F90 e GIBBS2F90. Os dados utilizados pertencem ao programa de melhoramento genético Geneplus - Embrapa. As herdabilidades para PC39, STAY5,2, STAY6,2 , PED e PES em análise unicaracterística foram 0,15, 0,20, 0,23, 0,28 e 0,36, respectivamente. Para o intervalo entre partos as estimativas de herdabilidade, obtidas em análise unicaracterística, para IEP1, IEP2, IEP3 e IEP4 foram 0,13 0,13, 0,12 e 0,17, respectivamente. Estes valores indicam que os ganhos por seleção direta em quaisquer um dos intervalos seriam pequenos.Na análise bicaracterística as herdabilidades para PC39 e PES foram 0,14 e 0,38,respectivamente. As estimativas obtidas foram de baixa magnitude, indicando que os ganhos por seleção direta em qualquer uma das características mensuradas nas fêmeas seriam baixos. Já o PED e PES apresentaram maiores valores de herdabilidades. A correlação entre PES e PC39 foi positiva e de baixa magnitude (0,25), sugerindo que a seleção para o aumento do PES de touros possivelmente levaria a pequenas mudanças na PC39. De modo geral as estimativas de herdabilidade para as características medidas nas fêmeas apresentaram baixos valores, enquanto que para as características medidas nos machos se apresentaram de moderada a baixa, de maneira semelhante à maioria dos estudos com estas características. Entretanto, o modelo de limiar foi capaz de detectar variância genética aditiva para as características em estudo, permitindo promover ganhos, embora pequenos, por seleção direta.
In the present study were obtained, in a population of Nellore cattle, estimates of genetic parameters for the characteristics probability of calving up to 39 months at age (PC39), stayability, considering three calving until 5.2 (STAY5,2) and trhee calving until 6.2 years old (STAY6,2), and the first four calving interval (CI1, CI2, CI3 and CI4), treated as categorical traits, and scrotal perimeter at weaning (EPD) and at 18 months of age (EPS), treated as continuos trait. Were used Baeysian procedures, in single and two trait analysis, by using THRGIBBS1F90 and GIBBS2F90 programs. Information from Nellore animals belonging to the Geneplus-Embrapa program was used. The heritabilities for PC39, STAY3,1, STAY3,2, EPD and EPS in single trait analysis were 0.14, 0.20, 0.23, 0.28 and 0.36, respectively. For the calving interval estimates heritabilities for CI1, CI2, CI3 and CI4 were 0.13, 0.13, 0.12 and 0.017, respectively. These values indicate that genetic gains by direct selection in any of the intervals would be very small. In the two trait analysis the heritabilities for PC39 and EPS were 0.15 and 0.38, respectively. The low values of estimates showed that small gains would be obtained by direct selection in any of traits measured in females. EPD and EPS had higher heritabilities. The correlation between EPS and PC39 was positive with low magnitude (0.25), suggesting that the selection for the increase of EPS of sires could possibly lead to small changes in the PC39. In general, estimates of heritability for traits measured in dams were low and for traits measured in males were moderate to low. This result is likely those reported in most studies with the same traits. However, the threshold model was able to detect additive genetic variance for the traits under study and can permit to promote gains, albeit small, by direct selection.
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20

Urbani, Nicola. "Microsatellite DNA analysis of the mating system during the first breeding period of the female snow crab Chionoecetes opilio (Brachyura, Majidae)." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35838.

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In order to study sperm competition and mating dynamics in the snow crab Chionoecetes opilio, a genomic library was established with the goal of identifying highly polymorphic microsatellite markers. Six pairs of DNA primers were designed to amplify markers Cop3-4, Cop4-1, Cop5, Cop10, Cop24-3 and Cop111 by the polymerase chain reaction (PCR). All markers produced patterns as expected from single loci inherited in a mendelian fashion, except for Cop5 which revealed a multi-locus banding pattern. The cross-amplification of the six loci in seven additional crabs species revealed DNA polymorphisms at one or more loci for each species. Markers Cop3-4 and Cop24-3 were used to determine paternity of larvae of primiparous females both from the wild and from multiple mating experiments under laboratory settings. The two markers were also used to genotype the contents of female spermathecae in order to determine the number of number of male genotypes present. Spermathecal contents of wild-caught females were cut into several cross-sections and each section genotyped individually. Histological analysis of spermathecae was carried out to complement genetic data in order to elucidate patterns of sperm competition. Single paternity was observed for the progeny of all females. The analysis of laboratory females showed displacement was the mechanism by which single paternity was obtained by the last males to mate. The analysis of wild females revealed that their spermathecae contained on average the sperm of at least 3.7 males. Larvae appeared to be sired by males whose genotypes were found in the spermathecal cross-sections toward the blind-end of the spermathecae. This suggested that they were the first males to mate with females they guarded until oviposition, and females remated with other males thereafter. Also, a comprehensive account of the mating dynamics was carried out in a wild population of the Northwest Gulf of Saint Lawrence (Eastern Canada) and demonstrated the e
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21

Salin, Maurício Marchesi [UNESP]. "Procapri: Programa de gerenciamento de rebanhos caprinos - versão 2.0." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/99603.

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Este trabalho teve como objetivo apresentar a nova versão do PROCAPRI (Programa de controle produtivo e reprodutivo de caprinos). A primeira versão do software foi desenvolvida em 1994, pelo Departamento de Zootecnia da Unesp de Jaboticabal em parceria com o Pólo Computacional da mesma unidade universitária, com objetivo de auxiliar caprinocultores no controle zootécnico de seus rebanhos e coletar dados para pesquisas. Após 12 anos de existência, vários fatores contribuíram para que surgisse a necessidade de reformular o programa, dentre eles, a popularização de microcomputadores em propriedades rurais e os avanços tecnológicos ocorridos tanto na caprinocultura como na informática. Foi realizada uma detalhada avaliação da primeira versão do programa e uma pesquisa com usuários para estabelecimento das atualizações necessária ao sistema. A principal alteração ocorrida no PROCAPR I foi o desenvolvimento do sistema para operar em ambiente Windows~' utilizando a ferramenta de desenvolvimento Delphi 7.0~. Além disso a nova versão foi implementada com novas opções para gerenciamento dos rebanhos caprinos tais como controle de estoque de sêmen e para registrar resultados de diagnóstico de gestação, opção para alocação de animais dentro do rebanho, entre outros. Dessa maneira será possível manter o programa atualizado para que continue sendo útil para os caprinocultores gerenciarem seus criatórios, gerando dados para as pesquisas, ensino e extensão na universidade e fortalecendo a caprinocultura.
The goal of this research was presented the version of PROCAPRI (Software to Goat Productive and Reproductive Control). The First version of the software was developed in 1994 for the Animal Science department of Unesp Jaboticabal wíth a partner Computing Center of the same University. The objective was helped producers to management of goats and formed data set to research. Over 12 years of existence, many factors were contributed for the necessities to reformulation of the software include popularization of the computing in the farms and the goat production advances. It was realized an evaluation of PROCAPRI 1.0 and a research wíth users for establishment the updates. The principal modification was a system development to Windows ambient. The new version of PROCAPRI was completed with new options to management of goat production. These modifications wíll be important to maintain the software updated for the users, collecting dataset to research and consolidating the goat production.
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22

Salin, Maurício Marchesi. "Procapri: Programa de gerenciamento de rebanhos caprinos - versão 2.0 /." Jaboticabal : [s.n.], 2006. http://hdl.handle.net/11449/99603.

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Resumo: Este trabalho teve como objetivo apresentar a nova versão do PROCAPRI (Programa de controle produtivo e reprodutivo de caprinos). A primeira versão do software foi desenvolvida em 1994, pelo Departamento de Zootecnia da Unesp de Jaboticabal em parceria com o Pólo Computacional da mesma unidade universitária, com objetivo de auxiliar caprinocultores no controle zootécnico de seus rebanhos e coletar dados para pesquisas. Após 12 anos de existência, vários fatores contribuíram para que surgisse a necessidade de reformular o programa, dentre eles, a popularização de microcomputadores em propriedades rurais e os avanços tecnológicos ocorridos tanto na caprinocultura como na informática. Foi realizada uma detalhada avaliação da primeira versão do programa e uma pesquisa com usuários para estabelecimento das atualizações necessária ao sistema. A principal alteração ocorrida no PROCAPR I foi o desenvolvimento do sistema para operar em ambiente Windows~' utilizando a ferramenta de desenvolvimento Delphi 7.0~. Além disso a nova versão foi implementada com novas opções para gerenciamento dos rebanhos caprinos tais como controle de estoque de sêmen e para registrar resultados de diagnóstico de gestação, opção para alocação de animais dentro do rebanho, entre outros. Dessa maneira será possível manter o programa atualizado para que continue sendo útil para os caprinocultores gerenciarem seus criatórios, gerando dados para as pesquisas, ensino e extensão na universidade e fortalecendo a caprinocultura.
Abstract: The goal of this research was presented the version of PROCAPRI (Software to Goat Productive and Reproductive Control). The First version of the software was developed in 1994 for the Animal Science department of Unesp Jaboticabal wíth a partner Computing Center of the same University. The objective was helped producers to management of goats and formed data set to research. Over 12 years of existence, many factors were contributed for the necessities to reformulation of the software include popularization of the computing in the farms and the goat production advances. It was realized an evaluation of PROCAPRI 1.0 and a research wíth users for establishment the updates. The principal modification was a system development to Windows ambient. The new version of PROCAPRI was completed with new options to management of goat production. These modifications wíll be important to maintain the software updated for the users, collecting dataset to research and consolidating the goat production.
Orientador: Kleber Tomás de Resende
Coorientadora: Izabelle Auxiliadora Molina de Almeida Teixeira
Banca: Atushi Sugohara
Banca: Silvio Doria de Almeida Ribeiro
Mestre
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23

Lombardi, Giorgio Colombo. "Variation in breeding systems, floral morphology and nectar properties in three co-occurring Erica species with contrasting pollination syndromes." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018567.

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The genus Erica is the most species rich in the Cape Floristic Kingdom, yet there are limited data on the various flower-pollinator interactions and breeding systems for the majority of these species. Until recently research has focussed on predictive floral traits, including flower shape, length of corolla and corolla opening to identify likely pollinators in this genus. Field observations provide an empirical test of such predictions. This study investigated three species of Erica and compared their pollination and breeding systems and floral biology. Research, including field experiments and pollinator observations was undertaken in the Vogelgat Private Nature Reserve, Maanschynkop Nature Reserve and Boskloof farm in the vicinity of Hermanus in the Western Cape Province of South Africa. Field observations were conducted to determine what flower- visitor interactions occurred, while nectar volumes and sugar concentrations were measured to determine the value of the reward to the different visitors. Selective exclusion and breeding system experiments were carried out to determine whether these Erica species were capable of autonomous self-fertilization or whether they are pollinator dependent for breeding success. The unusual morphology of Erica lanuginosa suggested rodent-pollination. Field observations, including photographs of visits to plants in the field, the presence of pollen in scat sample and selective exclusion and breeding system experiments identified rodents, primarily Acomys subspinosus to be the primary pollinator. Long-proboscid flies of the family Nemestrinidae were found, on the basis of field observations to be responsible for pollination of the endemic Erica aristata. This was supported by with nectar volume and sugar concentration samples which are consistent with other long-proboscid fly-pollinated plant species. Selective exclusion and breeding system experiments undertaken confirmed that Erica aristata required a pollinator to set seed. Observations and breeding trials revealed bird-pollination in Erica sessiliflora. Nectar volume and sugar concentrations in Erica sessiliflora were in line with other sunbird-pollinated plant species, providing the necessary rewards for sunbirds visiting this species. Specialised pollination by single pollinators was found in all three species and results from breeding system experiments show that out-crossing is important. Further research into pollinator-flower interactions in the genus Erica is necessary, not least to understand more fully the conservation importance of specific pollinators.
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24

Brumatti, Ricardo Carneiro. "Influência das técnicas reprodutivas e tipo de acasalamento em programas de seleção de gado de corte e seu impacto no custo e na produção de tourinhos." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-26022007-155756/.

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A seleção e produção de touros para o mercado pecuário tornam-se foco de muitos estudos, e um grande desafio para o segmento em se tratando da constante busca de melhorias nos desempenhos produtivos dessa categoria animal. A tese teve por objetivo simular o que poderá acontecer com a produção de reprodutores, em termos de quantidades produzidas e custos operacionais efetivos, sob a influência dos métodos de acasalamentos e das biotécnicas reprodutivas disponíveis no mercado nacional. A hipótese em questão é a de testar se acasalar matrizes, classificadas por genótipo, suas produções serão melhores do que quando comparada à produção de matrizes classificadas por fenótipo. Foram simulados 42 cenários produtivos, divididos em 21 cenários com acasalamento genotípico e 21 com acasalamento fenotípico. Em cada divisão constam simulações com uso de Monta Natural, Inseminação Artificial padrão e com sêmen sexado para machos, Transferência de Embriões padrão e com sêmen sexado para machos, Fecundação in vitro padrão e com sêmen sexado para machos, sendo que em todos os casos três níveis diferentes de taxas de concepção foram testados. Os resultados apontaram que o sistema de acasalamento teve influência direta na produção de tourinhos, sendo que o acasalamento por genótipo foi mais eficiente do que o acasalamento por fenótipo. As taxas de concepção influenciaram negativamente mais os resultados dos sistemas de acasalamento fenotípico. Há um grande aumento no custo operacional efetivo dos sistemas que utilizaram as biotécnicas reprodutivas de Transferência de Embriões e Fecundação in vitro, e consequentemente uma redução na lucratividade destes sistemas. As simulações com Monta Natural apresentaram as maiores Margens Brutas e as simulações com Inseminação Artificial com uso de sêmen sexado para machos apresentaram os maiores Lucros Brutos.
The selection and production of bulls for the cattle market have both become the goal of many studies, as well as a great challenge for the segment, providing the constant search for performance improvement of that sort of animal. The target of this thesis is to simulate what may happen to the production of stud, in terms of quantity and effective operational costs, under the influence of the mating methods and the available reproduction biotechniques in the national market. The hypothesis under analysis consists of testing if mating matrices, classed by their genotype, their produce will be better than when compared to the produce of phenotype-classed matrices. 42 productive-scenes, divided into 21 genotype mating and 21 phenotype mating were simulated. In each of the scene divisions there were the following simulations: Natural Breeding, standard Artificial Insemination, Artificial Insemination with male-gendered semen, standard Embryo Transference, Embryo Transference with male-gendered semen, standard In-vitro Fecundation and In-vitro Fecundation with male-gendered semen, so that in all the cases, three different conception rates were tested. The results displayed that the mating system directly influenced the young bull production, once the genotype mating was more efficient than the phenotype mating. The conception rates negatively influenced the results of the phenotype mating mainly. There was a dramatic increase in the effective operational cost of the systems that used the reproductive biotechniques of Embryo Transference and In-vitro Fecundation, and, consequently, profitability reduction of those systems. The Natural Breeding simulations presented the highest Gross Margin, and the simulations of Artificial Insemination with male-gendered semen showed the highest Gross Profit.
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25

Cortés, López Miguel Ángel. "Efecto de la PMSG en la sincronización del estro sobre el comportamiento reproductivo de ovejas de Pelo." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2016. http://hdl.handle.net/20.500.11799/65512.

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Tesis para obtención de título.
El presente estudio fue realizado en el rancho La Esperanza, localizado en San Pedro Limón, en el municipio de Tlatlaya, México; con el objetivo de evaluar la administración parenteral de 0 y 333 UI de gonadotropina de suero de yegua preñada (PMSG), en ovejas prímalas con sincronización del estro, 24 h antes del retiro de una esponja intravaginal conteniendo progestágenos (acetato de fluorogestona). Se utilizaron 28 ovejas prímalas Pelibuey blanco, con edad y peso promedio de 8 meses y 40 kg, respectivamente. Las ovejas fueron alimentadas en pastoreo rotacional, además del consumo de alimento balanceado (0.750 kg/cabeza/d) conteniendo 13.9% de PC y 2.6 Mcal g kg MS-1. El análisis de las variables, horas a inicio del estro, horas al estro y prolificidad, se realizó bajo un diseño completamente al azar, y la comparación de medias se realizó por medio de la prueba de Tukey. El porcentaje de estro y las tasas de gestación y partos se analizaron mediante ji-cuadrada. El porcentaje de estro fue de 100 % para ambos tratamientos, sin encontrar diferencia entre tratamientos. Los intervalos horas a la presentación de signos de estro y horas a estro fueron menores (P< 0.0001) en las ovejas que recibieron 333 UI de PMSG, con valores de 16.261 ± 7.27 h y 24.261 ± 7.27 h, respectivamente. La tasa de gestación y partos no fue afectada por los tratamientos. La prolificidad fue mayor (P< 0.01) en las ovejas que recibieron 333 UI de PMSG, en comparación a las ovejas que recibieron 0 UI de PMSG (1.667 vs. 1.000, respectivamente) En base a los resultados obtenidos se concluye que la inyección de 333 UI de PMSG, 24 h antes del retiro de la esponja intravaginal, en ovejas prímalas Pelibuey blanco, reduce el intervalo horas a estro y mejora la prolificidad.
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26

Martínez, Paredes Eugenio Melchor. "Rearing programmes for breeding rabbits. Effect of early development and feeding on future reproductive performance of rabbit females and males." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/124969.

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[ES] Cualquier mejora en el conocimiento de la nutrición y el manejo de los futuros conejos reproductores debe considerarse como prioritario en la producción cunícola. Sin embargo, los principales esfuerzos en investigación se han centrado en estos animales durante la fase de reproducción propiamente dicha. La hipótesis inicial de esta tesis fue que alcanzar un desarrollo temprano adecuado durante la gestación, lactancia, engorde y recría, con la ayuda de programas ajustados de alimentación en algunos de estos períodos, mejoraría el rendimiento reproductivo y la vida útil de los futuros conejos reproductores. Para evaluar esta hipótesis, se llevaron a cabo dos tipos de ensayos, tanto en conejos hembra de líneas maternas como en machos de líneas seleccionadas por velocidad de crecimiento y destinadas a la inseminación artificial. El primero de estos ensayos se centró en los diferentes patrones de crecimiento, desde el nacimiento hasta el final de la fase de recría, y su influencia en la carrera reproductiva y la vida útil del conejo. En el segundo tipo de pruebas, se evaluó el efecto del uso de diferentes dietas o programas de alimentación durante el período de recría en la productividad a corto y medio plazo. Los resultados muestran dos fases importantes en el desarrollo temprano, de acuerdo con sus efectos sobre el rendimiento reproductivo y la vida útil. Mostrar un mayor desarrollo corporal desde el nacimiento hasta los 63 días de vida parece tener una influencia positiva en el grado de madurez y la productividad al comienzo de su vida reproductiva, además de poder mejorar su supervivencia a corto plazo, pero con posibles efectos negativos en la esperanza de vida a largo plazo. Sin embargo, el desarrollo durante el período de recría (desde los 63 días de vida hasta el comienzo de la carrera reproductiva) parece tener un mayor impacto en la productividad y la esperanza de vida de nuestros futuros conejos reproductores. Las hembras más engrasadas en la primera inseminación tuvieron tamaños de camada más pequeños y un mayor riesgo de ser sacrificadas que las magras (P<0.05). Además, los machos que mostraron una mayor ganancia media diaria durante el período de recría tuvieron un número y porcentaje de eyaculados viables más bajos a lo largo de su vida productiva y mayor riesgo de muerte o sacrificio. Estos resultados podrían indicar que la clave para llevar a cabo un desarrollo adecuado durante el período de recría debería basarse tanto en conseguir que los conejos alcancen un grado de madurez apropiado, tanto fisiológica como reproductivamente, así como evitar un excesivo engrasamiento al inicio de su vida productiva. En los ensayos destinados a evaluar los programas de alimentación durante la recría, el uso de una restricción alimentaria en hembras, y especialmente el uso de dietas fibrosas (de 8.5 a 10 MJ ED/kg MS) permiten un desarrollo corporal gradual y adecuado a la edad de cubrición, con suficientes reservas corporales para afrontar el comienzo de la vida reproductiva y mejorando tanto su rendimiento reproductivo como su vida útil. El éxito de estos programas de alimentación de recría depende del momento y la duración de la aplicación de estos, mejorándose con la aplicación de un cambio a un pienso enriquecido energéticamente alrededor del primer apareamiento. En los machos, se observó que un programa de alimentación durante la recría adecuado debería adaptarse a la capacidad de ingesta de estos y a sus necesidades nutricionales en períodos concretos de la recría, consiguiendo así mejoras en algunos parámetros del semen al inicio de su vida reproductiva. En conclusión, tanto un desarrollo temprano adecuado desde la gestación hasta el comienzo de su vida reproductiva, como el uso de programas adecuados de alimentación durante la recría podrían mejorar significativamente el rendimiento reproductivo futuro, así como la esperanza de vida, tanto en conejos he
[CAT] Qualsevol millora en el coneixement tant de la nutrició com del maneig dels futurs conills de criança ha de considerar-se com a prioritari en la producció de conills. No obstant açò, els principals esforços en investigació s'han centrat en aquests animals durant la fase de reproducció pròpiament dita. La hipòtesi inicial d'aquesta tesi va ser que aconseguir un desenvolupament primerenc adequat durant la gestació, lactància, engreix i criança, amb l'ajuda de programes ajustats d'alimentació en alguns d'aquests períodes, milloraria el rendiment reproductiu i la vida útil dels futurs conills reproductors. Per a avaluar aquesta hipòtesi, es van dur a terme dos tipus d'assajos, tant en conills femella de línies maternes, com en mascles de línies seleccionades per a la velocitat de creixement i destinades a la inseminació artificial. El primer d'aquests assajos es va centrar en els diferents patrons de creixement, des del naixement fins al final de la fase de criança, i la seua influència en la carrera reproductiva i la vida útil del conill. En el segon tipus de proves, es va avaluar l'efecte de l'ús de diferents dietes o programes d'alimentació durant el període de criança, en la productivitat a curt i mig termini. Els resultats obtinguts semblen indicar que podríem diferenciar dues fases en el desenvolupament primerenc, d'acord amb els seus efectes sobre el rendiment reproductiu i la vida útil. Mostrar un major desenvolupament corporal des del naixement fins als 63 dies de vida sembla tenir una influència positiva en el grau de maduresa i la productivitat al començament de la seua vida reproductiva, a més de poder millorar la seua supervivència a curt termini, però amb possibles efectes negatius en l'esperança de vida a llarg termini. No obstant açò, el desenvolupament durant el període de sembla tenir un major impacte en la productivitat i l'esperança de vida dels nostres futurs conills reproductors. Les femelles més greixades en la primera inseminació van tenir grandàries de ventrada més xicotets (tant nascuts com deslletats) i un major risc de ser sacrificades que les magres (P<0.05). A més, els mascles que van mostrar un major guany mitjà diari durant el període de criança van tenir un nombre i percentatge d'ejaculats viables més baixos al llarg de la seua vida productiva i major risc de mort o sacrifici. Aquests resultats podrien indicar que la clau per a dur a terme un desenvolupament adequat durant el període de criança hauria de basar-se tant a aconseguir que els conills aconseguisquen un grau de maduresa apropiat, per a afrontar els futurs desafiaments productius, com evitar un excessiu greixatge a l'inici de la seua vida productiva. En els assajos destinats a avaluar els programes d'alimentació durant la criança, l'ús d'una restricció alimentària en femelles, i especialment l'ús de dietes fibroses (de 8.5 a 10 MJ ED/kg MS) permeten un desenvolupament corporal gradual i adequat a l'edat de cobriment, amb suficients reserves corporals per a afrontar el començament de la vida reproductiva i millorant tant el seu rendiment reproductiu com la seua vida útil. L'èxit d'aquests programes d'alimentació de criança depèn del moment i la durada de l'aplicació d'aquests, millorant-se amb l'aplicació d'un canvi a un pinso enriquit energèticament al voltant del primer cobriment. En els mascles, es va observar que un programa d'alimentació durant la criança adequat hauria d'adaptar-se a la capacitat d'ingesta d'aquests i a les seues necessitats nutricionals en períodes concrets de la criança, aconseguint així millores en alguns paràmetres del semen a l'inici de la seua vida reproductiva. En conclusió, tant un desenvolupament primerenc adequat des de la gestació fins al començament de la seua vida reproductiva, com l'ús de programes adequats d'alimentació durant la criança podrien millorar significativament el rendiment reproductiu futur, així com l'esperança
[EN] Any improvement on the knowledge of both nutrition and management of the future rabbit breeders should be considered as crucial. However, main research efforts have been focused on animals during reproduction phase. The initial hypothesis of this thesis was that achieving an adequate early development during young rabbits' gestation, lactation, fattening and rearing, with the help of fitted feeding programmes in some of these periods, would be improved reproductive performance and lifespan of the future breeding rabbits. To evaluate this hypothesis, two types of trials, both in rabbit females from maternal lines selected for litter size at weaning and males from paternal lines selected for growth rate and intended on artificial insemination, were carried out. The first of these trials were mainly focused on the different growth patterns, from birth to the end of the rearing age, and their influence on rabbit's reproductive career and lifespan. In a second type of trials, the effect of the use of different diets or feeding programs during the rearing period in the performance in the short- medium-term was evaluated. The results obtained from the evaluation of the different growth patterns trials seem to indicate that, we could differentiate two parts on the early development according to their effects on reproductive performance and lifespan. To show a greater body development from birth to 63 days of life seems to have a positive influence on the maturity degree and productivity at the beginning of their reproductive life, as well as being able to improve their survival in the short-term, but it could be even negative for long-term lifespan. However, the development during the rearing period (from 63 days of life to the beginning of reproduction career) seems to have a higher impact on the productivity and lifespan of our rabbit breeders. Fatter rabbit females at first insemination had smaller litter sizes (born and weaned) and a higher risk of being culled (+13% per positive change in mm of perirenal fat) than lean ones (P<0.05). Also, rabbit males that showed a greater average daily gain during rearing period had a lower number and percentage of profitable ejaculates through it productive life (-10.1 and -4.9% per each 10 g of daily gain increase, respectively; P<0.05) and higher risk of death or culling (+16.2% per each increase in one standard deviation unit on live weight; P<0.05). These results could indicate that the key to carrying out an adequate development during the rearing period should allow the rabbits to reach an appropriate degree of physiological and reproductive maturity to face the future productive challenges, avoiding an excessive fatness at the beginning of their productive life. The use of a feeding restriction in rabbit females, and especially the use of fibrous diets (from 8.5 to 10 MJ DE/ kg DM) lead a gradual and adequate body development at mating, with enough body reserves to face the beginning of reproduction life and improving their whole reproductive performance and lifespan. The success of these rearing feeding programs depends in the moment and duration of application of them and improved with the application of a nutritional flushing around first mating. In rabbit males, it was observed that an adequate rearing feeding program should adapt it to the male's intake capacity and their nutritional requirements rearing period, especially to their high DP needs at the beginning of rearing period or when their requirements were close to maintenance, to improve some semen parameters at the beginning of their reproduction life. In conclusion, both the adequate early development of future rabbit breeders, from their own gestation to the beginning of their reproductive life, and the use of appropriate rearing feeding programs could significantly improve their future reproductive performance, as well as their life expectancy, both in rabbit females and males.
Martínez Paredes, EM. (2019). Rearing programmes for breeding rabbits. Effect of early development and feeding on future reproductive performance of rabbit females and males [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/124969
TESIS
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Varela, Susana Araújo Marreiro. "Animal decision-making for habitat and mates : the selection of breeding commodities through inadvertent social information and its consequences for the evolution of coloniality." Paris 6, 2007. http://www.theses.fr/2007PA066668.

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Choisir où et avec qui se reproduire constituent deux des décisions les plus importantes dans la vie des animaux, vu son impact sur la valeur adaptative. Cela implique que les animaux utilisent de l’information sur la qualité de l’environnement pour identifier laquelle des alternatives existantes semblent être la plus avantageuse. Pour cela, ils peuvent choisir de façon indépendante de leurs congénères par l’évaluation directe des différents paramètres environnementaux, ou ils peuvent choisir de façon non indépendante de façon à réduire le temps et l’énergie investie dans l’échantillonnage de l’environnement (information sociale par inadvertance – ISI). Avec mes expériences chez la Drosophile, et mon étude comparative sur l’évolution de la colonialité chez les oiseaux, je mets en évidence pour la première fois que les invertébrés peuvent aussi utiliser ISI, et que ISI est probablement le mécanisme le plus plausible à l’évolution de la vie en groupe.
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28

Brand, Monica Merenza. "Reproduction criteria and meat quality of South African Black (Struthio Camelus var. Domesticus), Zimbabwean Blue (Struthio Camelus Australis) and South African Black X Zimbabwean Blue ostriches." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/1714.

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Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2006.
The aim of this study is to determine the effect of crossbreeding Zimbabwean Blue (ZB) and South African Black (SAB) ostriches on the morphological, physical, chemical and sensory quality of the meat. However, it is also necessary to determine the reproductive performance of these genotypes to scientifically support decisions made in the ostrich industry. In relation to reproductive traits and body measurements influencing these traits, results from the study suggested that ZB birds are between 9 and 15% heavier than their SAB contemporaries. Regarding SAB females, egg production was 47% higher, levels of shell deaths were lower, percentage of eggs not incubated was lower (P<0.01) and 84% more (P<0.01) chicks were produced in a season compared to their ZB contemporaries. Mates of SAB males produced a higher (P≤0.05) percentage of eggs not incubated and higher shell death percentages than the mates of ZB males. It has to be conceded that ZB females had a lower reproduction than SAB females, limiting the application of this genotype as a dam line in crossbreeding systems. With regard to morphological properties, the pure Blue genotype in comparison to the pure Black genotype differed significantly (P≤0.05), with 16 kg for live weight, 8.3 kg for carcass weight and 3.5 kg for leg weight. However, when comparing carcass yields (expressed as %) there were no significant differences (P>0.05) between genotypes. The M. gastrocnemius, M. femorotibialis accessorius, M. iliotibialis cranialis, M iliotibialis lateralis, M. iliofibularis and M. iliofemoralis showed significant genotype differences (P≤0.05) for individual muscle weight. When comparing the physical meat quality characteristics between the pure Blue genotype and the pure Black genotype, 70% of the muscles were higher (P≤0.05) in pH24, 50% of the muscles were redder (P≤0.05) and significantly less (P≤0.05) saturated in colour, 67% of the muscles had a lower (P≤0.05) percentage drip loss and 50% of the muscles had a lower (P≤0.05) percentage cooking loss. No significant (P>0.05) genotype differences were observed regarding the sensory quality of the meat. Regarding chemical meat quality characteristics, the percentage of moisture was higher and the percentage of lipid was lower for eight of the ten muscle groups from the pure Blue genotype. No significant differences (P>0.05) were found between genotypes or between muscles regarding the percentage of protein present in the meat. The highest (P>0.05) content of soluble collagen, myoglobin and cholesterol was found in the Blue x Black genotype, whereas the lowest percentage of the latter constituents was found in the pure Blue genotype. For the pure Black genotype the concentration of saturated fatty acids in the meat was lower (P≤0.05), the concentrations of total unsaturated fatty acids and desirable fatty acids in the M. illiofibularis were the highest (P≤0.05), while the concentration of monounsaturated fatty acids was also higher (P≤0.05) in both muscles of this genotype compared to the other two genotypes. Regarding both fat depots, the pure Black genotype had a lower (P≤0.05) concentration of saturated fatty acids, a higher (P≤0.05) concentration of monounsaturated fatty acids and total unsaturated fatty acids and a higher (P≤0.05) polyunsaturated:saturated fatty acid ratio. The percentage of desirable fatty acids in the abdominal fat depot was significantly higher (P≤0.05) for the pure Black and the Blue x Black genotype. In conclusion, crossbreeding between SAB and ZB ostriches seems to be a viable option to produce larger birds with more meat, without negatively affecting the overall quality of the meat.
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29

Trudelle, Laurène. "Distribution et préférences d'habitats des baleines à bosse de l'hémisphère Sud en période de reproduction." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS038/document.

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L’étude des déplacements des baleines à bosse (Megaptera novaeangliae) en relation avec les paramètres environnementaux permet d’apporter des informations précieuses sur leur distribution et leurs préférences d’habitats. Grâce à des données d’observations opportunistes collectées dans le canal de Sainte Marie (Nord-Est de Madagascar) et des données de télémétrie collectées pour cette étude (25 baleines équipées de balises Argos), cette thèse a pour objectif l’étude des déplacements et de l’utilisation de l’habitat des baleines à bosse de Madagascar en fonction du sexe et du statut reproducteur. Des variables physiographiques et océanographiques (mesurées par satelllite) ont été extraites sous chaque position. Un schéma général d’utilisation de l’habitat en période de reproduction a également été proposé à partir de données de télémétrie provenant de différentes zones de reproduction de l’Hémisphère Sud: le Brésil (n=82 individus), l’Australie de l’Ouest (n=26) et l’Australie de l’Est (n=11). Dans le canal de Sainte Marie, nos résultats ont montré une ségrégation temporelle d’un mois avec une première partie de saison dominée par les groupes avec baleineaux et une seconde dominée par les groupes sans baleineaux (Chapitre III). La profondeur influence la distribution des groupes sociaux avec une préférence des couples mère-baleineau pour les plus faibles profondeurs (< 20 m). Le long de la côte de Madagascar, les déplacements localisés des femelles sont associés à des habitats plus profonds et plus éloignés de la côte que ce qui avait été supposé (Chapitre IV). En revanche, les mâles ne semblent pas montrer de préférences d’habitats particuliers bien qu’ils diminuent leur vitesse de nage dans les zones peu profondes. En zone océanique, les individus se déplacent de façon plus erratique dans les eaux les moins profondes, de faible courant ou les plus riches en chlorophylle a. La vitesse du courant de surface ne semble pas être un facteur majeur dans le déplacement des baleines à bosse. Cependant, elles semblent suivre la même direction que celui-ci lorsque ce dernier est fort. Notre étude comparative entres les zones de reproduction a montré que la distribution spatiale varie selon la période de la saison, entre les sites étudiés et selon le sexe (Chapitre V). En début et fin de saison, les mâles se déplacent de manière plus directe et exploitent des zones plus au large que les femelles, notamment celles avec baleineau. Au pic de la saison, les mâles et les femelles effectuent des déplacements plus localisés. La prise en compte des différences dans la variabilité spatio-temporelle des mâles et des femelles en zone de reproduction apparait être une nécessité pour mieux comprendre l’écologie des baleines à bosse et contribuer à la conservation de l’espèce
Of key importance for the comprehension of humpback whales’ (Megaptera novaeangliae) distribution patterns and habitat use is to quantify how ecological and environmental factors affect the distribution of animals, which requires knowledge on dispersal movements of individuals. Using an opportunistic sightings dataset collected in the Sainte Marie Channel (Northeast of Madagascar) and satellite telemetry data acquired for this study (25 tagged whales), the aim of this thesis was to study the movements and the habitat use of humpback whales in Madagascar during the breeding season, according to sex and reproductive status. Physiographic and oceanographic variables (measured by satellite) were extracted under each position. A general distribution pattern of habitat use during the breeding season was also proposed based on additional humpback whales tracks from others breeding grounds of the Southern Hemisphere: Brazil (n=82 individuals), the Western Australian coast (n=26), and the Eastern Australian coast (n=11). In the Sainte-Marie Channel, groups without calves dominated the first 30 days of the breeding season, followed by an increase in groups with calves (Chapter III). Water depth influenced the distribution of social groups with mother-calf pairs more frequently found in relatively shallow water (0-20 m). Along the coast of Madagascar, over the shelf, females showed localized behavior in deep water and at large distances from shore suggesting that their breeding habitat extends beyond the shallow coastal waters (Chapter IV). Males’ active swimming speed decreased in shallow waters, but we found no influence of environmental parameters on males’ movements. In oceanic habitats, both males and females showed localized behaviors in shallow waters and high surface chlorophyll-a concentrations. The active swimming speed accounts for a large proportion of the whale observed speed while observed direction of tagged whales tending to be closer to the current direction when the current intensity was high. Our comparative study between breeding areas showed that the spatial distribution varies according to the period of the season, between the studied sites, sex and breeding status (Chapter V). Early and late in the season, males moved more directly and in more offshore areas than females, especially females with calves. At the peak of the season, both males and females performed more localized movements than at the other periods. Accounting for differences in the spatio-temporal variability of the distribution of males and females in the breeding grounds seems a necessity to better understand the humpback whales ecology and contribute to the species conservation
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30

Monday, Jessica Dawn. "Evaluation of peripubertal replacement breeding animals in beef herds." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35530.

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Master of Science in Veterinary Biomedical Science
Department of Clinical Sciences
Robert L. Larson
The selection of young replacement animals can have a significant impact on beef herd reproductive performance. Replacement heifers can be utilized to improve reproductive performance by replacing mature animals that failed to meet the production with young, cycling heifers that can have the potential of improving the reproductive momentum of a herd. The use of yearling bulls in natural breeding herds has the advantage of shortening the generational interval of the herd and has the potential of reducing the cost per cow exposed as additions to the bull battery. This thesis involves two studies that investigated methods used for the selection of peripubertal replacement animals in beef herds. The first study evaluated the ability of the novel Ready-Intermediate-Problem (RIP) replacement heifer evaluation matrix to classify heifers into groups that allow producers to select for replacements that meet production goals. Beef heifers (n=341) were classified according to the RIP matrix guidelines and then exposed to AI breeding, bull breeding, or a combination of both as per the management plans for each participating herd. Following breeding season the heifers were evaluated to determine pregnancy status, pregnancy status to single AI exposure, days bred, and the number of 21 day cycles needed during breeding season to become pregnant. After breeding season, 298 (87%) of the heifers were pregnant, 204 (68%) of which became pregnant in the first 21 days of the breeding season. Probability of overall pregnancy and pregnancy after single AI exposure was not significantly associated with RIP classification. There was a significant interaction in RIP classification by 21 day cycle. The second study was a retrospective study using BSE result data to determine the proportion of yearling beef bulls that are classified as satisfactory potential breeders when reevaluated after failing their initial breeding soundness evaluation (BSE) and to identify any predictive factors at initial BSE for satisfactory performance at revaluation. The study included 2,805 beef bulls between 11 and 14 months of age at first BSE evaluated at KABSU from 2006 to 2014. Generalized linear mixed models were created to assess potential associations among breed, age, and interaction between breed and age and passing the initial evaluation and identify predictive factors for risk of passing BSE after initial failure. The majority (93%) of the study bulls passed one of up to three BSEs. There was a significant interaction between age and breed of bull at initial BSE. Identification of suitable peripubertal replacement animals that will improve herd reproductive performance remains a challenge for producers. There are several factors that can affect replacement animals’ ability to perform according to expectations at the beginning of the breeding season. Classification of heifers into categories that can predict performance during breeding season with reasonable confidence can assist producers in identifying heifers that complement the reproductive performance goals of the herd. Utilizing BSE to identify bulls that have adequate semen quality as well as other traits important for breeding soundness is similarly important in reducing the risks of using young bulls for breeding.
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31

Lagrange, Paméla. "Déterminants de la survie et de la dispersion de reproduction par une approche capture-marquage-recapture chez l'Hirondelle bicolore au Québec." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS077/document.

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En Amérique du Nord, la superficie des monocultures utilisatrices d'intrants tels que des fertilisants et des pesticides couvre aujourd'hui 85% des surfaces agricoles et autant de pâturages ont disparu en 20 ans afin de répondre aux besoins de l'homme. Ces changements d'usage des terres ont profondément transformé le paysage et altéré la biodiversité des agro-écosystèmes. Parmi les espèces d'oiseaux champêtres, les insectivores aériens tel l'Hirondelle bicolore, Tachycineta bicolor, ici étudiée, présente un fort taux de déclin des effectifs, reflétant probablement une dégradation des agro-écosystèmes. Les mécanismes biologiques à l'origine de ce déclin sont encore méconnus ainsi que les patrons de dispersion chez les passereaux migrateurs. Le présent travail vise à étudier les effets environnementaux sur les traits individuels (survie et succès reproducteur) et la dispersion de reproduction (probabilité de disperser et taux d'occupation des sites de reproduction) chez l'Hirondelle bicolore. Pour ce faire, 2200 reproducteurs et 8000 oisillons ont été bagués entre 2004 et 2013 et suivis en reproduction pendant 10 ans sur une aire d'étude au Sud du Québec, laquelle est composée de 40 sites et couvre une mosaïque de paysages agricoles hétérogènes. Le développement d'un nouveau modèle de capture-marquage-recapture, flexible d'utilisation, a permis de réduire les biais d'estimation des probabilités de survie et de dispersion de l'espèce. Cette approche a permis de tester l'effet de plusieurs variables en lien avec la qualité de l'habitat, l'information publique et les caractéristiques individuelles sur la variabilité des paramètres de dispersion, de survie et de succès reproducteur au niveau individuel. Les milieux cultivés intensivement associés à la présence du Moineau domestique, Passer domesticus, un compétiteur pour les cavités de reproduction, diminuent jusqu'à 19% la survie des mâles. Les femelles sont quant à elles affectées par le coût de la reproduction, qui est d'autant plus grand en milieu intensif qu'il y a présence de moineaux et une disponibilité moindre en ressources alimentaires. Pour autant, la décision de disperser n'est pas affectée par les conditions environnementales que ce soit par la présence de compétiteurs ou la qualité du milieu, et ne dépasse pas les 4% chez les mâles. Les femelles dispersant jusqu'à 14 fois plus s'appuient sur leur expérience personnelle pour décider de disperser. Un échec de reproduction augmente jusqu'à 7 fois la probabilité de disperser et pour la première fois chez une espèce à courte durée de vie, nous montrons que la probabilité de disperser est augmentée l'année suivant une première dispersion. Ces patrons de dispersion sont stables dans le temps. La dispersion apparait donc comme un processus coûteux, comparé à la fidélité au site, qui apparaît comme un phénotype minoritaire dans la population. Elle répond à des conditions défavorables de reproduction. Enfin, ce travail montre l'utilisation de l'information publique (densité en partenaires, productivité en jeunes l'année précédente) dans la décision de s'établir sur un site et ce, une fois que la décision de disperser est amorcée. La présence de moineaux et la proportion de cultures intensives dans un rayon proche participent également à la sélection d'un site. D'après mes résultats, le milieu intensif contribuerait au déclin de l'Hirondelle bicolore
In North America, monoculture areas using high inputs of fertilizers and pesticides cover 85% of agricultural lands, and as many pastures disappeared in the past 20 years to satisfy human food needs. These land-use changes have deeply transformed landscapes and altered the biodiversity of agro-ecosystems. Among farmland birds, aerial insectivores such as Tree swallow, Tachycineta bicolor, studied here show a high rate of decline in their abundance, partly reflecting the degradation of agro-ecosystems where they breed. Biological mechanisms leading to the decline and dispersal patterns in migratory passerines are still poorly known. The present work quantifies the environmental effects on Tree swallow individual traits (survival, reproductive success) and breeding dispersal (probability to disperse and occupation rates of breeding sites). Between 2004 and 2013, 2200 breeders and 8000 chicks were ringed and monitored during 10 breeding seasons on a study area composed of 40 sites and covering a mosaic of heterogeneous agricultural landscapes in southern Québec. The development of a new, flexible capture-mark-recapture model has reduced estimate bias of survival and dispersal probabilities of Tree swallows. This approach allowed to assess the effect of several variables linked to habitat quality, public information and individual characteristics on dispersal, survival and reproductive success parameters of individuals. Within intensively cultivated landscapes associated to the presence of a nest site competitor, the House sparrow, Passer domesticus, male survival is up to 19% lower. Females are affected by the cost of reproduction, especially in intensive landscapes where House sparrows and found and where food resources and nest site appear limited. Dispersal probability is not affected by environmental conditions either through the presence of House sparrows or habitat quality, and is restricted to 4% in males. Females, which disperse up to 14 times more than males, base their decision on their personal experience. Breeding failure increases up to 7 times the probability to disperse and for the first time in a short-lived species, I show that dispersal likelihood increases if the individual has dispersed in the previous year. These dispersal patterns are stable in time. Dispersal appears as a costly process compared to site fidelity and is a minority phenotype in the population. It appears an answer to unfavorable condition for reproduction. Finally, this work shows the use of public information (partners density, fledglings productivity the previous year) on the decision to settle on a site and this, after the dispersal decision has been initiated. The presence of House sparrows and the proportion of intensive areas near nestboxes are used as information to select a breeding site. Based on my findings, agricultural intensification likely plays a role in the decline of Tree swallow populations
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32

Danchin, Étienne. "Rôle des facteurs comportementaux dans les mécanismes de régulation des populations d'oiseaux coloniaux : cas de la mouette tridactyle (Rissa tridactyla)." Paris 6, 1988. http://www.theses.fr/1988PA066180.

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33

Récapet, Charlotte. "Keeping the balance ? : Management of oxidative stress, body mass and reproduction under energetic constraints by dispersing and philopatric collared flycatchers." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10272/document.

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La dispersion, c’est-à-dire le déplacement d’un individu entre deux sites de reproduction, est un processus clé pour la dynamique des métapopulations et les flux de gènes. Son succès peut être modulé par des différences de phénotype ou syndromes de dispersion. Cependant, les contraintes environnementales (externes) et physiologiques (internes) qui sous-tendent ces syndromes restent mal connus. Ce projet vise à clarifier l’impact des variations environnementales et des contraintes oxydatives (liées aux espèces réactives de l’oxygène produites durant la respiration) sur les phénotypes associés à la dispersion chez un passereau, le gobemouche à collier Ficedula albicollis. La demande énergétique a été expérimentalement (i) augmentée en manipulant la surface alaire ou (ii) diminuée par une supplémentation en nourriture. L’équilibre oxydo-réducteur des gobemouches en reproduction est influencé par des interactions complexes entre facteurs intrinsèques (statut de dispersion) et extrinsèques (densité de couples reproducteurs, année, traitement expérimental). La capacité antioxydante dépend principalement des différences permanentes entre individus, alors que les pro-oxydants présentent de grandes variations intra-individu. Les variations environnementales et les contraintes énergétiques modulent aussi les différences de succès reproducteur et de comportement parental liées au statut de dispersion. Nos résultats confirment que les oiseaux dispersants et philopatriques diffèrent dans leur gestion de l’équilibre oxydo-réducteur lorsqu’il est en compétition avec l’investissement reproducteur. Ces différences pourraient avoir des conséquences à long terme sur la valeur sélective et compenser les différences de succès reproducteur entre individus dispersants et philopatriques dans les habitats de faible qualité. Ce travail souligne que les traits associés à la dispersion sont souvent déterminés par des normes de réaction à l’environnement et non des différences fixées entre individus, et améliore notre compréhension des syndromes de dispersion
Dispersal, i.e. individual movement between breeding sites, is a key process for metapopulation dynamics and gene flow. Its success can be modulated by phenotypic differences between dispersing and philopatric individuals, or dispersal syndromes. However, the environmental (external) and physiological (internal) constraints underlying such syndromes remain poorly known. This project aimed at clarifying the impact of environmental variation and oxidative constraints, linked to the reactive oxygen species produced during respiration, on phenotypes associated to dispersal in a passerine bird, the collared flycatcher Ficedulla albicollis. Energetic demand was experimentally (i) increased through a wing load manipulation or (ii) relieved through food supplementation. The oxidative balance of breeding flycatchers was influenced by complex interactions of dispersal status and extrinsic factors (breeding density, year, experimental treatments). Interestingly, antioxidant capacity was influenced both by permanent individual differences and by food availability, whereas measures of pro-oxidants were highly variables within individuals. Environmental variation and energetic constraints also modulated the differences in reproduction associated with dispersal: dispersing and philopatric birds differ in their management of the oxidative balance when it is competing with reproductive investment. This thesis highlights that reaction norms, rather than fixed differences, often shape traits associated to dispersal
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34

Leon, Victor Enrique Gomez. "Biometria e mudanças morfológicas uterinas e ovarianas em fêmeas bovinas." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/5190.

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Assessment criteria directly related to sexual ability of the female, should be used in routine practice of Brazilian cattle, allowing the evaluation of development and function of organs that controls reproduction. Within all reproductive organs, the uterus has essential roles in sexual reproductive animals, controlling luteal function, as well as interfering in the transport, capacitation of sperm, and initial embryo implantation and development, housing, nurturing and protecting the fetus until calving. Thus, at the first stage of the study, were analyzed ultrasound images of cross sections at first uterine region (uterine internal bifurcation, and horns, until the beginning of the greater curvature), at second uterine region (from the greater curvature until just before the tip of the horn) and at third region (the free end of the horn) of five sexually mature Holstein female cattle uterus, created and managed in Losing-House. In vivo and post mortem, animal reproductive organs, were measure with the purpose of verify the accuracy of the interpretation and measures of uterine biometry (diameter and endometrial thickness of the uterine horns), standardizing the methodology. Quantitative data were analyzed by ANOVA and the means compared by Tukey test or Duncan test or by the nonparametric analysis with Kruskal Wallis test or Wilcoxon test. It was considered the probability of 5 % error in all analyzes. There was no difference between the values of the uterine biometry for measurements in animals in vivo and in reproductive organs post mortem (P>0.05). Mean values for measurements in vivo animals, at first region, for left uterine horn diameter (21.0±2.6 mm), left horn endometrial thickness (10.4±4.9 mm), right uterine horn diameter (22.9±2.8mm), and right horn endometrial thickness (10.8±5.2 mm) were similar to values obtained in the other two regions (P>0,05). The values obtained demonstrate the technique's efficiency and high accuracy measuring uterine biometry from ultrasound images. The technique shown to be easily to perform. Thereafter, changes in the uterine biometry of 38 Holstein heifers, created in Tie-Stall, in the pre-puberty, puberty and sexual maturity were studied and evaluated by transrectal ultrasonography technique, every two weeks for a period of two months. The animals were divided into classes at every 3 months old, in order to encompass the reproductive events during the growth of the animals. At first class the Holstein heifers showed asynchronic growth, being found positive correlations in weight and height, and negative between weight and evaluated sexual characteristics. The heifers reached puberty between 12 and 15 months of age, fact that maximized the development of the uterine horns, endometrial thickness, and reproductive function at subsequent class. In the last experimental stage, uterine biometry changes at the estrous cycle of heifers 172 pubertal-induced and 90 single adult Nellore cows, raised in extensive managements, were studied under different protocols of Fixed- Time Artificial Insemination and the day of FTAI was aspirated the oocyte from the dominant follicle of every female. Afterwards the animals were submitted to natural mating. The artificial insemination protocols showed satisfactory values for induction of puberty and pregnancy in pre-pubertal heifers (68 %), and efficient for single adult Nellore cows (98 %). FTAI protocols can induce uterine changes reported in the literature, within the phases of the estrous cycle (under progesterone concentrations the endometrium has a glandular epithelium thickened, branched, folded and increased secretion of the glands (Producing ultrasound endometrial images thinner and increased echogenicity). However, it has not been proven protocols effect in pregnant rates, follicular growth rate and oocyte quality.
Critérios de avaliação diretamente relacionados à capacidade sexual da fêmea devem ser utilizados na prática de rotina da pecuária, permitindo avaliar o desenvolvimento e a função dos órgãos que controlam a reprodução. Dentre os órgãos genitais, o útero tem funções essenciais na reprodução sexual dos animais, controlando a função luteal, além de interferir no transporte e capacitação dos espermatozoides, como também na implantação e desenvolvimento inicial do embrião; alojamento, nutrição e proteção do feto até o final da gestação. Dessa forma, na primeira etapa deste estudo foram analisadas imagens ultrassonográficas de cortes transversais do útero. Na primeira região uterina (da bifurcação interna dos cornos uterinos até o início da curvatura maior), na segunda região (a partir da curvatura maior até pouco antes do ápice do corno) e na terceira região (ápice da extremidade livre do corno) no útero de cinco fêmeas bovinas sexualmente maduras da raça Holandesa, criadas em manejo de Losing- House. As medidas foram obtidas no animal in vivo e no órgão genital post mortem, com a finalidade verificar a acurácia das interpretações e medidas da biometria uterina (espessura endometrial e diâmetro dos cornos uterinos). Todos os dados quantitativos foram analisados por ANOVA e as médias comparadas pelos testes de Tukey ou Duncan ou então pela análise não paramétrica com as médias comparadas pelo teste de Kruskall Wallis ou Wilcoxon. Considerou-se a probabilidade de 5 % de erro em todas as análises. Não houve diferença entre os valores da biometria uterina para os mensurações no animal in vivo e no órgão genital post mortem (P>0,05). Os valores médios para as mensurações no animal in vivo, na região um, para diâmetro do corno uterino esquerdo (21,0±2,6 mm), espessura endometrial do corno esquerdo (10,39±4,9 mm), diâmetro do corno uterino direito (22,9±2,8 mm), e espessura endometrial do corno direito (10,8±5,2 mm), se mostraram semelhantes aos valores obtidos nas outras duas regiões. A obtenção e correta interpretação de imagens transversais da primeira região do útero (início da bifurcação uterina até a curvatura maior) por meio da ultrassonografia transretal bovina, mostra-se uma metodologia com alta acurácia e eficiente para avaliar a biometria uterina (espessura e diâmetro dos cornos uterinos). Posteriormente, com ajuda da ultrassonografia foram estudados os desenvolvimentos ponderal e sexual de 38 fêmeas da raça Holandesa, criadas em Tie-Stall, nas fases de pré-puberdade, puberdade e maturidade sexual (nove a 20 meses de idade). As fêmeas foram avaliadas a cada quinze dias por um período de dois meses, sendo mensurados peso e altura, e as mudanças que aconteceram na biometria uterina por meio da ultrassonografia via transretal. Os animais foram divididos por classes com intervalos de 3 meses de idade, com a finalidade de abranger os eventos reprodutivos durante a fase de crescimento. As alturas dos animais da classe 3 e 4 foram semelhantes entre si (P>0,05) e maiores dos animais das classes 1 e 2 (P<0,05), apresentando alta correlação com o peso corporal (r= 0,8). O útero das novilhas apresentou diâmetros maiores do corno esquerdo nos animais das classes 3 e 4 (P<0,05). A espessura endometrial do corno direito foi maior em animais da classe 4 (P<0,05). Concluiu-se que o desenvolvimento ponderal e o sexual ocorrem de forma assincrônica nos animais mais jovens (9 -11 meses), sendo o ponderal mais acelerado; a puberdade de fêmeas da raça Holandesa nas condições tropicais se manifestam entre as faixas etárias de 12 a 15 meses de idade causando consequentemente retraso na maturidade sexual; uma vez atingida a puberdade o desenvolvimento ponderal e sexual é sincrônico e o aumento da espessura endometrial e diâmetro dos cornos uterinos se maximizam. Na ultima etapa experimental foram estudadas as alterações da biometria uterina nas fases do ciclo estral de 172 novilhas induzidas à puberdade e 90 vacas adultas solteiras da raça Nelore, criadas em regime extensivo, submetidas a diferentes protocolos de sincronização, aspirando o ovócito do folículo dominante no dia e horário correspondente à IATF. Posteriormente, os animais foram inseminados a cio detectado e submetidos ao manejo de monta natural. Os protocolos de inseminação artificial mostraram valores satisfatórios para indução de puberdade e gestação nos estros subsequentes em novilhas pré-púberes (68 %), e eficientes em vacas adultas solteiras da raça Nelore (98 %). Os protocolos de sincronização conseguiram induzir as mudanças uterinas relatadas na literatura, concluindo que no ciclo estral bovino, durante a fase folicular e sob o efeito do estrógeno, são obtidas imagens ultrassonográficas hipo-ecogênicas da camada endometrial com aumento da espessura da mesma com imagens anecogênicas do lume uterino em algumas ocasiões. Na fase luteal e sob a influência da progesterona, são obtidas imagens ultrassonográficas da camada endometrial hiper-ecogênicas e diminuição na espessura da mesma. O diâmetro dos cornos uterinos de novilhas nulíparas e vacas solteiras da raça Nelore, criadas em regime extensivo, mostraram-se próximos aos valores de referência (20 mm) preconizados para fêmeas maturas sexualmente, aptas à reprodução.
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35

Ponchon, Aurore. "Comportements individuels et réponse des populations aux changements environnementaux : la mouette tridactyle comme modèle." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20235/document.

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Le but de cette thèse est d'étudier les comportements individuels liés à la sélection de l'habitat de reproduction chez un oiseau marin colonial longévif, la mouette tridactyle et de déterminer leur importance dans la réponse des populations aux changements environnementaux à différentes échelles spatiales et temporelles. Dans un premier temps, des approches expérimentales incluant un suivi du mouvement des individus par GPS et balises Argos ont permis de démontrer que seuls des individus en échec de reproduction effectuent des mouvements de prospection impliquant la visite d'autres zones de reproduction. Ces mouvements ont été enregistrés depuis la période de fin d'incubation jusqu'à la période d'élevage des poussins à des échelles spatiales aussi bien locales (<1km) que régionales (> 40 km), dans des conditions environnementales variées. Ensuite, un modèle de dynamique des populations considérant différentes stratégies de dispersion a montré que contrairement à la philopatrie et la dispersion aléatoire, l'utilisation d'informations personnelle et sociale par les individus permet aux populations de maintenir des effectifs élevés et de persister sur le long-terme. Enfin, des modèles de captures-recaptures ont mis en évidence des interactions indirectes entre protocoles de suivis à long-terme d'individus marqués et comportements individuels liés à la dispersion. Ces interactions peuvent notamment biaiser l'estimation de paramètres démographiques tels que le taux de survie annuelle. L'ensemble de nos résultats démontre que la sélection de l'habitat de reproduction et la dispersion sont des processus complexes mais essentiels dans la compréhension du fonctionnement des populations et qu'ils doivent être mieux pris en compte dans les modèles prédictifs de dynamique, structure et persistance des populations en réponse aux changements environnementaux
The aim of this thesis is to study individual behaviours linked to breeding habitat selection in a long-lived colonial seabird, the black-legged kittiwake, and to determine their importance in population responses to environmental changes occurring at different spatial and temporal scales. First, experimental approaches including GPS and satellite tracking of individuals allowed demonstrating that only failed breeders performed prospecting movements involving visits of other breeding areas. These movements were recorded from egg incubation to chick rearing at local spatial scales (<1 km) as well as large spatial scales (> 40km), in various environmental conditions. Then, a population dynamic model considering different dispersal strategies showed that contrarily to philopatry and random dispersal, personal and social information use by individuals favoured population persistence in the long-term. Finally, capture-recapture models highlighted indirect interactions between sampling designs of long-term surveys of marked individuals and behaviours linked to dispersal. These interactions can notably bias the estimation of demographic parameters such as annual survival rate. All our results demonstrate that breeding habitat selection and dispersal are complex but essential processes in the understanding of population functioning and they have to be considered in models predicting the dynamics, structure and persistence of populations in response to environmental changes
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Prata, Marco Aurélio. "Índices econômicos de seleção para rebanhos Gir Leiteiro." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-05012017-141219/.

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A produção de leite em geral é a característica mais importante em programa de melhoramento animal de rebanhos leiteiros. Vários estudos tem sido conduzidos para no Gir Leiteiro envolvendo a estimação de parâmetros genéticos para características produtivas nos últimos anos, mas pequena atenção foi dada a saúde do úbere e características reprodutivas. Os índices de seleção são utilizados em vários países para selecionar animais mais lucrativos e para quantificar a resposta correlacionada entre as características a serem incluídas como objetivos de seleção. Este trabalho tem como objetivo desenvolver um estudo visando a construção de índices de seleção para posterior utilização na classificação e seleção dos animais avaliados no programa de teste de progênie de bovinos Gir Leiteiro no Brasil. Componentes de (co) variância para a produção de leite (PL), gordura (G), proteína (P), porcentagem de gordura (G%), porcentagem de proteína (P%), escore de células somáticas (ECS), intervalo de partos (IDP) e idade ao primeiro parto (IPP) foram estimados usando informações de desempenho fornecidas pela Associação Brasileira de Criadores de Gir Leiteiro (ABCGIL). Os dados incluíram registros de 10.146 vacas, filhas de 1005 touros, com partos ocorridos entre 1989 e 2013, distribuídas em 289 rebanhos. As análises estatísticas foram realizadas utilizando modelo animal, em análises bivariadas pelo método de máxima verossimilhança restrita (REML). Sete diferentes índices foram propostos (chamados GPI = Gir Performance Index), com alternativos objetivos de seleção e fatores de ponderação. GPI-1: PL + G +P, incluindo os respectivos valores econômicos (VE$) das características. GPI-2: PL + P + IDP + IPP, incluindo os respectivos valores econômicos (VE$) para as características reprodutivas e ponderação zero para IDP e IPP; GPI-3: PL + P + IDP + IPP, incluindo os respectivos valores econômicos (VE$) para as características produtivas e para IDP, e ponderação zero para IPP. Baseados nas possíveis respostas esperadas obtidas nos índices anteriores, diferentes fatores de ponderação foram atribuídos para as características do GPI-4 ao GPI-7. GPI-4: 0.20*PL + 0.40*P - 0.30*IPP - 0.10*IDP; GPI-5: 0.10*PL + 0.50*P - 0.10*IPP - 0.30*IDP; GPI-6: 0.10*PL + 0.60*P - 0.10*IPP - 0.20*IDP e GPI-7: 0.10*PL + 0.30*P - 0.20*IPP - 0.40*IDP. O GPI-1, GPI-2, GPI-3 e GPI-4 apresentaram maiores respostas para a produção de leite. Pequenas diferenças nas respostas para P foram observadas entre os índices. A resposta para IDP diminuiu do GPI-1 ao GPI-7 o que pode ser favorável, pois diminuiria o IDP. Entretanto, não foram obsevadas grandes diferenças entre as respostas econômicas, indicando que é possível a seleção para características reprodutivas sem diminuir o lucro. Os resultados sugerem que a seleção somente para produção de leite poderia levar a um declínio no desempenho reprodutivo. A inclusão da PL, P, IDP e IPP como objetivos de seleção no programa desenvolvido pela ABCGIL poderia promover um equilíbrio entre o melhoramento das características produtivas e reprodutivas. No entanto, espera-se lenta resposta à seleção devido às baixas estimativas de herdabilidade das características.
Milk production traits in general are the most important trait in dairy cattle breeding program. Several studies have been conducted on Gir cattle involving the estimation of genetic parameters for milk production traits over last years, but small attention was given to udder health and reproductive traits. Selection indexes have been used around the world to select more profitable animals and to quantify the correlated response among all traits included in the breeding goal. Thus, the main goal of the present study was to develop a selection indexes for future use in the classification and selection of animals evaluated in a breeding program of Gir dairy cattle in Brazil. The estimate genetic parameters for 305d milk yield (MILK); fat yield (F), fat content (F%), protein yield (P), protein content (P%), lactation somatic cell score (LSCS), calving interval (CI) and age at first calving (AFC), were calculated using information on milk and reproduction traits provided by the Brazilian Association of Gir Dairy Breeders (ABCGIL). Dataset included records of 10,146 cows, daughters of 1,005 sires, who calved between 1989 and 2013, reared in 289 herds. The statistical analyses were carried out by an animal model, in bivariate analyses using the restricted maximum likelihood method. Seven different situations were created in the present study to define the breeding goals for Gir Dairy cattle (named GPI = Gir Performance Index). GPI-1; MILK + F + P, including the respective economic values (EV$) of traits; GPI-2: Milk + P + AFC + CI, including the respective economic values (EV$) for milk traits and zero for CI and AFC; GPI-3: M + P + AFC + CI, considering EV ($) for MILK, P, CI and zero for AFC. Based on possible expected responses obtained from previous indexes, different weighting factors were attributed to traits in GPI-4 to GPI-7. GPI-4: 0.20*MILK + 0.40*P - 0.30*AFC - 0.10*CI; GPI-5: 0.10*MILK + 0.50*P - 0.10*AFC - 0.30*CI; GPI-6: 0.10*MILK + 0.60*P - 0.10*AFC - 0.20*CI and GPI-7: 0.10*MILK + 0.30*P - 0.20*AFC - 0.40*CI. GPI-1, GPI-2, GPI-3 and GPI-4 provided higher genetic responses for MILK. Small differences on responses were observed for P across all indexes. Responses for CI decreased from GPI-1 to GPI-7, which could be favorable, however no differences among the economic selection response were observed, indicating that is possible include reproduction traits in the index without decrease the profit. These results suggest that the selection based only on the improvement of milk yield could lead to a decrease in reproduction performance. These results suggest that inclusion of MILK, P, CI and AFC traits in the breeding goals in the breeding program developed by ABCGIL could generate a balanced improvement of production and reproduction traits. However, is expected smal response to selection due to low heritability estimates for these traits.
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37

Littlefield, Joanne. "Improved Horse Breeding: Equine Reproduction Research and Education." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2005. http://hdl.handle.net/10150/622196.

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Matthews, Merran Lisa. "Breeding systems and pistil structure in the family proteaceae." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phm441.pdf.

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Bibliography: leaves 173-184. This study aimed to broaden understanding of breeding systems in Australian Proteaceae and to study the optimum requirements for promotion of seed germination in two lesser researched genera with horticultural potential, Dryandra quercifolia and Dryandra formosa. The timing and pattern of stigma receptivity was determined using a combination of techniques. Findings can be used to breed and improve these species for further commercialisation in cut flower and garden industries. The study of pistil structure further identified the potential of this structure to affect the capacity of a proteaceous flower to be fertilised. Aspects such as the morphology and size of the stigmatic cavity and the quantity of transmitting tissue in the style were highlighted as filters to pollen tube passage. Comparative studies with other angiosperm species confirmed the unusual structure of the pistil of the proteaceous flower. Seed germination was found to be promoted by exposure of seeds to controlled temperatures of 15°C.
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Mays, Nora Ann 1952. "Hormonal correlates of reproductive behavior in the cooperatively breeding Harris' hawk (Parabuteo unicinctus)." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277088.

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I correlated the plasma titers of testosterone (T), estradiol (E), luteinizing hormone (LH), progesterone (P), corticosterone (B) and prolactin (Prl) with the reproductive behavior of breeders and adult and juvenal-plumaged helpers of the Harris' Hawk. During nest building, breeding males and adult male helpers had higher T levels than those in immature male helpers. Among females, only breeders had elevated T levels during nest building. During nest building, breeding females had higher E levels than those in adult and immature females helpers. Patterns of LH were similar to those of T and E. Concentrations of P and B varied only with handling time. During incubation, Prl titers were elevated only in breeding males and females. In contrast to other altricial species, all breeders showed no elevation in Prl levels during feeding of young. Among males, adult male helpers had the highest Prl levels while feeding young.
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40

Fowler, P. A. "Aspects of reproduction and heterothermy in seasonally breeding mammals." Thesis, University of Aberdeen, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377370.

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41

Patterson, Michael E. "Piping plover breeding biology and reproductive success on Assateague Island." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43276.

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I studied the piping plover on Assateague Island during the 1986 and 1987 breeding seasons. In 1987, I estimated the population to be 69 pairs. During both years, plovers nested on only a few portions of the island. I think that this pattern of nesting was determined by the distribution of three types of foraging habitats: bayside mud and sand flats, saltwater pools formed by storm tides, and a drawn down waterfowl impoundment. Reproductive rates were lower than two recent estimates of the level necessary to maintain a stable population. The primary problem was poor nest success and the leading cause of nest loss was nest predation by red foxes (Vulpes vulpes) and raccoons (Procyon Iotor). I was not able to identify factors responsible for chick mortality, but my data show a relationship between chick survival and foraging habitat. Broods feeding on bayside foraging areas had a much higher survival rate than broods which did not have access to these areas. Management efforts should focus on reducing nest predation. Recent experiments have indicated that predator exclosures constructed around individual nests can be used to reduce nest predation. These exclosures should be tested on Assateague. Future research efforts should focus on the role of foraging habitat in breeding site selection and the relationship between chick survival and the type of foraging used.
Master of Science
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42

Thompson, Robin. "Statistical methods and applications to animal breeding." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/30836.

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This thesis comprises a collection of 39 research papers divided into three groups. The first group is entitled 'Statistical Methods, including variance component estimation with general application'. The second group report on 'Application of statistical methods to animal breeding studies'. The last group 'Experimental Studies' reports on studies on animal breeding data in beef and dairy cattle. The major theme of Group I is variance component estimation and the introduction of a method, now known as REML (Residual Maximum Likelihood) that unifies the area. The method was introduced for the analysis of incomplete block designs with unequal block size but was found to have important applications in the analysis of groups of trials, time-series, multivariate data and detecting outliers. The work on variance components has applications to animal breeding and is discussed in Group II. Papers discuss efficient designs for estimation of genetic parameters, including heritability, maternal and multivariate genetic parameters. These designs can lead to substantial reductions in the variances of the parameters over classical designs. It is shown that REML can be applied in certain circumstances when there is selection of animals. Links between variance estimation and best linear unbiased prediction are explored. Methods of prediction, estimation of genetic parameters and optimal designs are given for non-normal data. The last group includes reports on the comparison of breeds and cross-breeding in beef cattle in Zambia. Other studies include estimating the genetic relationship between beef can dairy characters in british Friesian cattle. The validity of models used in dairy sire evaluation are investigated including the heterogenity of heritability of milk yield at different levels of production and a novel method for taking account of environmental variation within herds.
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Gilchrist, Jason Scott. "Reproduction and pup care in the communal breeding banded mongoose." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423945.

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44

Rattiste, Kalev. "Life History of the Common Gull (Larus canus) : A Long-Term Individual-Based Study." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis (AUU), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7350.

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45

Souza, Fransérgio Rocha de. "Perda de gestação e incidência de fêmeas repetidoras de estro em rebanho leiteiro mestiço." Universidade Federal de Uberlândia, 2012. https://repositorio.ufu.br/handle/123456789/13053.

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The objective of the studies was evaluate the effects of the animal category, season of calving, season of artificial insemination (AI), parity, numbers of previous inseminated and days in milk (DIM) at AI on pregnancy losses (PL) and the incidence of pregnancy loss before and after 60th day post-AI from females repeat breeders (FRB) and the effects of the animal category, season of calving, parturition condition and parity on the incidence of FRB. Data from Study 1 were collected from 462 pregnancies and calving of lactating dairy cows and from 118 pregnancies of heifers and the Study 2 from 997 pregnancies and calving of lactating dairy cows and from 371 pregnancies of heifers. Pregnancy check was performed by ultrasound between days 28 and 44 post-AI and re-checked between days 45 and 60 post-AI. The rates of pregnancy loss before 60th day and the incidence of RB were higher in lactating dairy cows than heifers (11.90% vs. 3.4%, P=0.01 and 24.5% vs. 6.5%, P<0.001, respectively) and pregnancy loss after day 60 was not affected by animal category (P=0.58). The season of calving affected the pregnancy loss before 60th day (which was higher in spring/summer) and there was only tendency (P=0.078) in affecting the incidence of RB cows probably due to the worst postpartum recovery. There was no relationship between season of AI, parity, number of previous inseminated and DIM at IA and pregnancy loss before and after 60th day in lactating dairy cows. The parturition condition had no effects on RB incidence, however, the effect of parity was detected. Even in crossbred lactating dairy cows the incidence of overall pregnancy loss and RB condition was higher and could be considered as a factor that compromised the reproduction efficiency.
Objetivou-se com este estudo avaliar os efeitos da categoria animal, estação do parto, estação da inseminação artificial (IA), ordem de lactação, número de inseminações prévias e dias em lactação (DEL) na IA sobre as perdas de gestação (PG) e a incidência de PG antes e após 60 dias da IA de fêmeas repetidoras de estro (FRE), bem como os efeitos da categoria animal, estação do parto, tipo de parto e ordem de lactação na incidência de FRE. Os dados do experimento 1 foram coletados de 462 gestações e partos de vacas leiteiras em lactação e de 118 gestações de novilhas, e do experimento 2 de 997 gestações e partos de vacas leiteiras em lactação e 371 gestações de novilhas. O diagnóstico de gestação foi realizado por ultrassonografia entre os dias 28 e 44 pós-IA e a confirmação entre 45 e 60 dias pós-IA. As taxas de PG antes do 60º dia e a incidência de FRE foram maiores em vacas leiteiras lactantes que em novilhas (11,90% vs. 3,4%; P=0,01 e 24,5% vs. 6,5%; P<0,001, respectivamente), e a perda após 60 dias não foi afetada pela categoria animal (P=0,58). A estação do parto afetou a perda antes do 60º dia (que foi maior na primavera/verão) e houve apenas uma tendência (P=0,078) em afetar a incidência de vacas RE, provavelmente devido à pior recuperação no pós-parto. Não houve relação entre estação da IA, ordem de lactação, número de inseminações prévias e DEL na inseminação e PG antes e depois do 60º dia em vacas leiteiras lactantes. O tipo de parto não afetou a incidência de FRE, porém, o efeito da ordem de lactação foi detectado. Até mesmo em vacas leiteiras mestiças a incidência de perda geral de gestação e de FRE foi alta e pode-se considerá-los como problemas reprodutivos que comprometem a eficiência reprodutiva.
Mestre em Ciências Veterinárias
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46

Somerville, Alison Joan. "Advantages to late breeding in Ruddy ducks." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25045.

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Ruddy Ducks in the Chilcotin parklands of British Columbia nest in late June, July and early August, later than most other waterfowl species breeding in southwestern British Columbia, Canada. This thesis considers factors that may affect the timing of breeding in Ruddy Ducks by comparing Ruddy Ducks to Barrow's Goldeneye and Bufflehead (species that breed early but do not renest) and to American Coot (a species that breeds early and is able to renest). These factors include predation, flooding and desertion of nests, feeding behavior of ducklings, abundance of food, availability of green vegetation and fluctuations in temperature. Possible advantages of late breeding include reduced nest predation and higher ambient temperature during incubation. Longer dive durations and more frequent feeding and resting by Ruddy ducklings may enable ducklings to maximize energy for growth. Reduced nest flooding late in the season, dependence on green vegetation for nesting and greater abundance of food for young in summer were not demonstrated by this study. Therefore, these factors apparently do not explain the timing of breeding in Ruddy Ducks in southwestern British Columbia. Despite insufficient time to renest and shorter time for ducklings to mature before ponds freeze, the average number of 2B age class young produced per pair of Ruddy Ducks was similar to that of American Coots. Forty percent of nesting Ruddy females did not hatch any young, whereas almost all nesting Coot females successfully hatched young; however, survival of Ruddy ducklings to 2B age class (four weeks old) was higher than that of American Coots, Barrow's Goldeneye and Bufflehead.
Science, Faculty of
Zoology, Department of
Graduate
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47

Catry, Paulo X. "Ecology and behaviour of Great Skuas breeding on Foula (Shetland)." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388551.

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48

Alarcón, Caballero Rocio Anali, Yllatopa Frank Bazalar, Velarde Bryan Fabricio Meneses, Basilio Isabel Ventura Soto, and Navarro Victor Enrique Urrutia. "Proyecto de aplicativo móvil EQUIVAPP." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/656953.

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En el presente trabajo, se presentará el desarrollo del prototipo del aplicativo móvil EQUIVAPP, el cual busca conectar personas que laboran dentro de la industria ganadera y equina, facilitando de esta manera la comunicación con una cartera de clientes y servicios especializados en el sector, otorgando un nivel alto de confianza mediante la oferta de una gran variedad de productos valorados y puntuados por los mismos usuarios. En otras palabras, lograr posicionarnos dentro de los clientes como un aplicativo que les ayuda ahorrar tiempo y pérdidas por contar con un gran número de posibles socios con valoraciones que les aseguran una calidad premium de los servicios que requiere. Asimismo, estarán presentes, dentro del aplicativo, todos los servicios que quieran acceder que estén dentro de reproducción, transporte, venta de alimentos balanceados o especiales y veterinaria. La elaboración de este proyecto está centrada en acabar con el gran nivel de pérdidas registradas dentro del sector, puesto que la gran mayoría de contactos que poseen muchas de las empresas son obtenidas por recomendaciones de vecinos o trabajadores aledaños. Asimismo, la implementación de tecnología dentro de un sector rural no es un gran problema, puesto que la mayoría de las familias dedicadas a este sector, cuentan con las nuevas generaciones que vienen actualizadas con el manejo de celulares, computadoras, laptops y demás dispositivos tecnológicos.
In this paper, we will present the development of the prototype of the mobile application EQUIVAPP, which seeks to connect people working in the livestock and equine industry, thus facilitating communication with a portfolio of customers and specialized services in the sector, providing a high level of confidence by offering a variety of products valued and rated by the same users. In other words, to position ourselves within the customers as an application that helps them save time and losses by having a large number of potential partners with ratings that will ensure a premium quality of the services required. Likewise, all the services they want to access in the areas of reproduction, transport, sale of balanced or special feed and veterinary services will be present in the application. The development of this project is focused on putting an end to the high level of losses registered within the sector, since most of the contacts that many of the companies have are obtained through recommendations from neighbors or neighboring workers. Likewise, the implementation of technology in a rural sector is not a big problem, since most of the families dedicated to this sector have new generations that are up to date with the use of cell phones, computers, laptops and other technological devices.
Trabajo de investigación
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(9788879), Nicholas Corbet. "Measuring reproductive traits in tropical beef cattle breeds: Implications for genetic evaluation." Thesis, 2020. https://figshare.com/articles/thesis/Measuring_reproductive_traits_in_tropical_beef_cattle_breeds_Implications_for_genetic_evaluation/13407578.

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Reproduction in beef cattle herds is a key driver of productivity and profitability of beef enterprises. Improving the efficiency of reproduction is necessary to keep pace with an increasing global demand for animal protein. Grazing lands across northern Australia, however, comprise large areas of relatively lowly productive land-types with hot, dry climates and unpredictable seasonal rainfall. The challenge for many north Australian beef enterprises is to improve reproduction in the tropically adapted beef breeds grazed extensively in these regions. Environmental factors influenced by climate and herd management practices account for a proportion of the variation in reproduction rate, but underlying genetic factors also explain individual animal differences. Industry-wide genetic improvement of herd reproductive performance has generally been slow, mainly due to perceptions of low heritability, late expression of the trait and difficulty in capturing the necessary joining and calving data. However, selection line experiments in research herds have demonstrated genetic improvement in pregnancy rates of 3% to 5% per annum in tropically adapted breeds. Likely contributors to the genetic differences seen in selected animals are the higher heritability of component traits of reproduction and genetic correlation of these component traits with reproductive performance. This study incorporates a series of experiments conducted across 9 years and reports moderate to high heritability of reproductive component traits. The traits studied included age at puberty and post-partum anoestrus in females; and scrotal circumference and percent morphologically normal sperm in males. In addition, the study reports moderate genetic correlation between these key component traits and lifetime reproduction. The estimated genetic parameters indicate that selection for genetic improvement of these attributes of reproduction, in conjunction with sound breeder-herd management, offers a sustainable solution to the challenge of improving reproductive efficiency in north Australian herds. The perceived challenge of data collection required for genetic evaluation, however, remains a barrier to the adoption of genetic improvement strategies by north Australian beef producers. With the aim of refining and automating data collection, the final two experiments report on the use of ultrasound scanning, on-animal devices and radio-frequency identification sequence through walk-over-weigh systems to autonomously record behavioural oestrus and predict time of conception in post-partum cows. Further detailed studies are required, but on-animal devices could potentially provide a suite of technologies to help reduce the challenge of recording and formatting data. Coupled with data handling software platforms, these technologies could provide beef producers with the necessary information on individual animals to more readily develop strategies for genetic improvement of reproductive efficiency.
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(9819326), Donald Menzies. "The use of Precision Livestock Management technologies to record reproductive efficiency in the northern Australian beef industry." Thesis, 2017. https://figshare.com/articles/thesis/The_use_of_Precision_Livestock_Management_technologies_to_record_reproductive_efficiency_in_the_northern_Australian_beef_industry/13444376.

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Abstract:
The northern Australian beef industry is dominated by cow-calf operations where reproductive efficiency has a major effect on profitability, particularly related to extended post-partum anoestrus intervals and high perinatal losses. Recording the post-partum anoestrus interval (PPAI) and distinguishing causes of perinatal loss requires the date and location of calving to be accurately known, both of which are traditionally laborious and costly. The original contribution to knowledge of this research is through the use of autonomous data collection systems to enable the recording of date and location of calving and assigning maternal parentage. The thesis firstly investigates the precision of an automated radio location device in a static array. Secondly, the device is further researched for its ability to derive date and location of calving when used in an intravaginal apparatus. The third experiment investigates the use of Walk-over-Weighing (WoW) technology to derive maternal parentage based on the temporal sequence with which cows and calves had their identity recorded. The final experiment investigates the use of WoW to derive the date of calving based on the weight loss associated with parturition.
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