Thèses : « Feeding and reproduction »

1

Fontana, Eddy Alejandro. « Effects of various male feeding regimens on reproduction in broiler breeders ». Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43750.

Texte intégral

Résumé :

A study was conducted using commercial broiler breeders with the males fed a diet containing, either 120/0 or 140/0 protein and body weight maintained at either 900/0 or 1000/0 of that recommended by the primary breeder (fed separately), or allowed to eat from the female feeders (controls). Female feeders in the separately fed pens were equipped with especially designed grills, which denied access to the males. The male feeder in these pens was elevated so that females were denied access.

Males fed separately (body weight 90% or 1000/0, and dietary protein 120/0 or 140/0) had a significantly higher percentage fertility (4.20/0) than males allowed to eat with the females. No differences in percentage fertility were found among the four separately fed groups. No differences were noted in percentage hatch of fertile eggs among any of the treatment groups.

Males eating from the female feeders had significantly heavier body weights and testes weights at 65 weeks of age than breeder males in the separately fed, groups. Mean body weights were 3819g and 4773g at 35 weeks of age, and 4192g and 5443g at 65 weeks of age for males eating separately and eating with the females, respectively. Furthermore, males in the control group had significantly larger breast angle measurements when compared with the separately fed males. No differences were observed in foot scores and semen concentration among males in the various treatment groups.

Master of Science

Styles APA, Harvard, Vancouver, ISO, etc.

2

Hellemans, Simon. « Ecology and reproduction of neotropical soil-feeding termites from the Termes group ». Doctoral thesis, Universite Libre de Bruxelles, 2019. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/286072.

Texte intégral

Résumé :

The traditional view of a lifelong monogamy between a king and a queen has recently been challenged in termites. In several species, multiple parthenogenetically-produced secondary queens replace the primary queen and mate with the primary king; this strategy is referred to as “Asexual Queen Succession” (AQS). The aim of my thesis was to investigate the modalities of reproduction and the ecology of neotropical soil-feeding termites from the Termitinae, with a focus on the inquiline termite Cavitermes tuberosus in the Termes group.In the first axis, we investigated the modalities of reproduction of C. tuberosus. (i) AQS is the main reproductive strategy of this species. (ii) The evolution of AQS requires the propensity of parthenogens to develop into neotenic queens. In C. tuberosus, secondary queens develop from a developmental stage of “aspirants” which participate to the social tasks usually undertaken by workers, as long as the primary queen is alive. (iii) In AQS species, a female-biased sex ratio is expected in the dispersing reproductives. In C. tuberosus, sex ratio varies among years and according to the type of reproductives, and the population sex ratio is balanced. These results raise hints on queen-king conflict over the sex ratio.In the second axis, we described the ecology and symbioses of C. tuberosus. (iv) Wolbachia, an endosymbiotic bacterium mainly known for manipulating the reproduction of arthropods in order to enhance its own transmission, infects all individuals in societies. This bacterium, particularly abundant in a gut-associated bacteriome, may play a role in the nutrition of C. tuberosus; both partners would have evolved a mutualistic symbiosis. (v) Inquiline termites live in a nest built by other termite species and do not forage outside. Physico-chemical measures and microbiota sequencing revealed that C. tuberosus is a generalist nest-feeder.Finally, we expanded our study of the breeding systems in the phylogenetic proximity of C. tuberosus. (vi) We described Palmitermes impostor, a new genus and species as a sister-group to the genus Cavitermes. (vii) AQS is the main reproductive strategy in P. impostor, and queens of Spinitermes trispinosus and Inquilinitermes inquilinus are able to reproduce parthenogenetically. Therefore, it appears likely that the conditional use of sexual and asexual reproductions is a preadaptation common to the whole Termes group, and that it evolved into a stable element of their breeding system at least in some species.Overall, our results open new perspectives in the understanding of reproductive strategies in termites and their relationships with their bacterial symbionts.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

Styles APA, Harvard, Vancouver, ISO, etc.

3

Oh, Chul-Woong. « Life history and population dynamics of the crangonid shrimps Crangon crangon and Philocheras trispinsus on Port Erin Bay, Isle of Man ». Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367117.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

4

Taylor, Robin M. « Plant nectar contributes to the survival, activity, growth, and fecundity of the nectar-feeding wandering spider Cheiracanthium inclusum (Hentz) (Miturgidae) ». Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1086114717.

Texte intégral

Résumé :

Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xii, 138 p.; also includes graphics. Includes abstract and vita. Advisor: Richard A. Bradley, Dept. of Evolution, Ecology, and Organismal Biology. Includes bibliographical references (p. 124-138).

Styles APA, Harvard, Vancouver, ISO, etc.

5

Kassetas, Cierrah Jordan. « Effects of Feeding 60% Dried Corn Distillers Grains Plus Solubles on Yearling Bull Reproduction ». Thesis, North Dakota State University, 2020. https://hdl.handle.net/10365/31799.

Texte intégral

Résumé :

Thirty-six half-sibling Angus bulls were assigned one of three diets: 1) 60% corn-based (CON; S = 0.18%; n = 12); 2) 60% DDGS replacing corn (60DDGS; S = 0.55% DM; n = 12); 3) CON diet + equivalent sulfur of 60DDGS added as calcium sulfate (SULF; S = 0.54%; n = 12) to evaluate the effects of feeding diets containing DDGS or calcium sulfate on performance and semen characteristics. Bulls began the study at 9 months of age and gained 1.6 kg/day for 112 days. Treatment by day interactions (P < 0.05) were observed for glutathione peroxidase and trace mineral concentrations in seminal plasma. Effects of treatment (P < 0.05) were observed for semen kinematics and triiodothyronine in serum. Alterations observed when feeding 60% DDGS to developing bulls occurred in a manner that is not dependent on dietary sulfur; therefore, observed changes could be related to other components within DDGS.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Vilchez, Niceas Carlos. « Effect of supplemental dietary fat on the reproductive performance of hens of turkey and Japanese quail ». Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61252.

Texte intégral

Résumé :

Four experiments were conducted on hens of turkey and Japanese quail. In Experiment I, turkey hens were fed diets containing either 0% added fat, 3.5% animal-vegetable fat blend (AV) or 3.5% dry fat product (DF). In Experiment II with turkey hens, 2 holding diets and 4 breeder diets were investigated. The holding diets contained either 0% added fat or 5% of AV. The breeder diets contained 0% added fat of 5% of one of the following: AV, corn oil (CO) or olive oil (OO). In Experiment III with Japanese quail, 3 pre-breeder (PB) and 3 breeder diets (BD) were studied. They contained either 0, 3.5 or 7% added AV. In Experiment IV with Japanese quail, all diets contained 97% of a semi-purified basal diet and 3% of one of the following: corn starch (CS), corn oil (CO), palmitic acid (PA), oleic acid (OA), linoleic acid (LA) or linolenic acid (LN). The fatty acid composition of plasma and yolk lipids of both turkeys and quail was influenced by the fatty acid composition of the diets. Quail fed a CO diet deposited more linoleic acid in the egg than did those on a LA diet. (Abstract shortened by UMI.)

Styles APA, Harvard, Vancouver, ISO, etc.

7

Wilkin, Philip John. « A study of the medicinal leech, Hirudo medicinalis (L), with a strategy for its conservation ». Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/7885.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

8

Stephens, Lisa Anne. « The effect of feeding hay containing high levels of molybdenum on reproduction in beef heifers ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ38982.pdf.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

9

Oresanya, Temitope Frederick. « Effects of feeding flaxseed to sows during late gestation on lactation and litter performance ». Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33434.

Texte intégral

Résumé :

A study was conducted to investigate the effect of supplemental fat from flaxseed (FL) on fatty acid (FA) profile, chemical composition, energy value of colostrum and milk, and litter performance. On day 107 of gestation a total of 59 large white sows were selected, blocked by parity and randomly allotted to one of three diets, 15% flaxseed (FL), 10% fullfat soybean (SB) or a control commercial (CO) diet containing corn and soybean meal. Diets were isocaloric and isonitrogenous but differed in fat content and FA composition. Colostrum and milk were collected soon after farrowing and on day 7, respectively, for fatty acid and chemical analysis. Dietary treatments did not affect sow feed consumption, weight loss, number of live pig born and weaned per litter. Similarly, pig birth weights, and day 7, 14, and 21 weights did not differ among treatment groups. FL significantly (p < 0.05) increased linolenic (LNA C18:3co3) and decreased palmitic (C16:0) and oleic (C18:1) acids in colostrum. FL also significantly (p < 0.001) increased LNA and arachidonic acid (C20:4) in milk, while it decreased myristic (C14:0), palmitic and palmitoleic (C16:1) acids. Chemical analysis showed no significant differences in total solids (TS) and energy value of colostrum while a significant (p < 0.05) increase in TS, fat concentration and energy value was observed in milk from FL. A total of 335 piglets were used in the plasma study of lipid metabolites. Triglyceride (TG), cholesterol, HDL cholesterol and glucose were not affected by dietary treatment (p > 0.05). Feeding FL to sows during late gestation and lactation enriches sow milk and piglets with LNA.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Skov, Martin Wiggers. « Reproduction and feeding ecology of East African mangrove crabs, and their influence on forest energy flow ». Thesis, University of Liverpool, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250459.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

11

Naturil, Alfonso Carmen. « EFFECT OF FEED RESTRICTION IN A RABBIT LINE SELECTED FOR GROWTH RATE ON REPRODUCTIVE PERFORMANCE : OVULATION INDUCTION, OOCYTE QUALITY, EMBRYONARY AND FETAL LOSSES ». Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/73065.

Texte intégral

Résumé :

[EN] The general aim of this thesis was to reproductively characterize females from a rabbit line selected for growth rate and to evaluate the effect of different nutritional strategies (ad libitum and restricted), in order to improve the reproductive performance. In chapter 1, the influence of maternal and embryonic genotype on prenatal survival and fetal growth was evaluated and contrasted with a maternal line. Prenatal survival, fetal weight and fetal placenta weight were affected by both embryonic and maternal genotype. Nevertheless, no differences were detected either at transcriptomic level in fetal placenta or in progesterone and IGF-I plasma levels in these females. It may be concluded that in rabbit females from paternal lines both embryonic and maternal genotypes are key factors in the reproductive performance of these females. The aim of chapter 2 was to explore the causes of ovulation failures in these rabbit females. Results showed that non-ovulated females presented lower LH plasma concentration as well as higher body weight and leptin and BOHB plasma levels than ovulated females. Thus, ovulation failures in females from line R could be attributed to decreased LH plasma concentrations in these females which may be related with their higher body weight and leptin levels. The following three chapters were focused on improvement of the reproductive performance of these females through a different nutritional strategy: a feed-to-appetite diet of these females after the rearing period and prior to insemination. The initial hypothesis was that the females are submitted to a restricted nutritional regimen which is not enough to cope with their needs during reproduction, causing long-term disturbances of energy balance which leads to the subsequent reproductive problems. Chapter 3 aimed to determine if a feed-to-appetite nutritional strategy would affect the hypothalamus-hypophysis axis and the quality of the produced oocytes, by transcriptomic analysis. While no differences were found in the microarray analysis of the hypothalamus-hypophysis, small differences were detected in the transcript expression analysis in oocytes of a group of genes selected. MSY2 was found to be downregulated in oocytes from restricted females. As a key regulator of maternal RNA transcription and translation, changes in this essential gene could explain some of the reproductive problems of these females. Whether the differences found at oocyte level were inherent at embryonic level and so involved in the drop of fertility was studied in Chapter 4. Although no significant differences were revealed in ovulation, embryo recovery, and implantation rate, higher fetal and gestational losses were found in restricted females, as well as lower fetal growth. Thus, we concluded that the nutritional strategy employed may have an impact on the oocyte (Chapter 3), but we also demonstrated that these changes were inherited by the embryo, and result in disturbances in gestational losses and fetal growth. The final chapter of this thesis was conducted to determine whether these effects on reproductive and metabolic elements were also evident in females following the common semi-intensive farm production system. Although the results obtained showed small variances in NEFAs and BOHB plasma levels, and also in body weight, no differences were detected in global reproductive performance in terms of fertility, prolificacy and productivity. The results obtained established that although differences are found at oocyte level and inherited by embryo and fetus, no improvements are reached with the proposed nutritional strategy in terms of reproductive performance when females selected for growth rate lead a normal semi-intensive production system.
[ES] El objetivo general fue la caracterización reproductiva de las hembras de una línea de conejo seleccionada por velocidad de crecimiento y el efecto de distintas estrategias nutricionales (ad libitum y restringidas), con la finalidad de mejorar el rendimiento reproductivo. En el capítulo 1 se evaluó la influencia de los genotipos materno y embrionario en la supervivencia prenatal y crecimiento fetal, entre las hembras de esta línea y una línea maternal. La supervivencia prenatal, peso fetal y el peso de la placenta resultaron afectados por los genotipos tanto embrionario como materno, pero no se detectaron diferencias sobre la placenta fetal a nivel del transcriptoma ni en los niveles de progesterona e IGF-I. Por lo tanto, se puede concluir que en éstas tanto el genotipo embrionario como el materno son factores clave en su rendimiento reproductivo. El objetivo del capítulo 2 fue explorar las causas de los fallos reproductivos en estas hembras. Los resultados mostraron que las hembras que no ovularon presentaban menores niveles de LH, un mayor peso corporal y mayor concentración en sangre de leptinas y BOHB, que aquellas que había ovulado. Por ello, los fallos en ovulación detectados en estas hembras podrían estar relacionados con una reducción en los niveles de LH, consecuencia del mayor peso de estas hembras y de los incrementados niveles de leptinas. Los siguientes capítulos se enfocaron a la mejora del rendimiento reproductivo de estas hembras empleando una estrategia nutricional distinta: la ingesta ad libitum de alimento tras el periodo de crianza hasta el momento del comienzo de su vida reproductiva. La hipótesis de partida fue que estas hembras son sometidas a un régimen nutricional restringido que no es suficiente para satisfacer sus necesidades energéticas durante la reproducción, lo que causa alteraciones en su balance energético que se manifestarían en los problemas reproductivos observados. El capítulo 3 trató de determinar a través de un análisis trasncriptómico si la estrategia nutricional planteada afectaría el eje hipotalámico-hipofisario y la calidad de los ovocitos. Aunque no se encontraron diferencias en el análisis de un micrarray realizado sobre el hipotálamo-hipófisis, sí que se detectaron en la expresión génica de los ovocitos. El transcrito MSY2 mostró una menor expresión en los ovocitos de las hembras restringidas. Este gen es un regulador clave en la maduración ovocitaria, por lo tanto, cambios en la expresión de este gen podrían explicar algunos de los problemas reproductivos de estas hembras. En el capítulo 4 se estudió si las diferencias a nivel ovocitario eran heredadas por el embrión pudiendo causar la baja fertilidad de estas hembras. Aunque no se encontraron diferencias en las tasas de ovulación, recuperación embrionaria e implantación, sí que aparecieron diferencias en las pérdidas fetales y gestacionales, así como un menor crecimiento fetal en los embriones procedentes de hembras con restricción alimentaria. Por ello, concluimos que la estrategia nutricional empleada tiene unas consecuencias en el ovocito (Capítulo 3), y demostramos que estos cambios parecen continuar en el embrión, resultando en alteraciones en pérdidas gestacionales y crecimiento fetal. El capítulo final fue desarrollado para evidenciar si los efectos reproductivos y metabólicos observados en los capítulos previos se manifestaban en las hembras que se encuentran en un sistema de producción tradicional en granja. A pesar de que los resultados mostraron variaciones en los niveles circulantes de NEFAs y BOHB y de peso corporal, no se encontraron diferencias en el rendimiento reproductivo global a nivel de fertilidad, prolificidad y productividad. Los resultados obtenidos parecen indicar que a pesar de las diferencias encontradas a nivel ovocitario, embrionario y fetal, con el régimen nutricional propuesto no se logra alcanzar mejoras en la eficiencia reproductivo de las h
[CAT] L'objectiu general va ser la caracterització reproductiva de les femelles d'una línia de conill seleccionada per velocitat de creixement i l'efecte de diferents estratègies nutricionals (ad libitum i restringides), amb la finalitat de millorar el rendiment reproductiu. En el capítol 1 s'avaluà la influència dels genotipus matern i embrionari en la supervivència prenatal i el creixement fetal, entre les femelles d'aquesta línia i les de una altra línia maternal. La supervivència prenatal, el pes fetal i el pes de la placenta resultaren afectats pels genotipus embrionari i matern, però no es detectaren diferències en la placenta fetal a nivell de trascriptoma ni en els nivells de progesterona i IGF-I. Per tant, en les femelles de conill seleccionades per velocitat de creixement, tant el genotipus embrionari com el matern són factors clau en el seu rendiment reproductiu. L'objectiu del capítol 2 va ser explorar les causes de les fallades reproductives en aquestes femelles. Les femelles que no ovularen presentaren menor nivells de LH, major pes corporal i major concentració de leptines i BOHB que aquelles que sí que hi havia ovulat. Per això, les fallades d'ovulació detectades en aquestes femelles podrien estar relacionades amb la reducció en els nivells de LH, com a conseqüència del major pes d'aquestes femelles i dels incrementats nivells de leptines. Els capítols següents s'enfocaren a la millora del rendiment reproductiu d'aquestes femelles mitjançant una estratègia nutricional distinta: la ingesta ad libitum d'aliment després del període de criança i fins al moment de l'inici de la vida reproductiva. La hipòtesi de partida fiu que aquestes femelles són sotmeses a un règim nutricional restringit que no és suficient per a satisfer les seves necessitats energètiques durant la reproducció, la qual cosa provoca alteracions en el balanç energètic que podrien manifestar-se en els problemes reproductius observats. El capítol 3 tractà de determinar mitjançant un anàlisi trasncritòmic si la estratègia nutricional plantejada podria afectar l'eix hipotalàmic-hipofisiari i la qualitat dels ovòcits. Metre que no es detectaren diferències en el anàlisi del microarray realitzat en el hipotàlem-hipòfisi, sí que es detectaren en l'expressió gènica del ovòcits. El transcrit MSY2 mostrà una menor expressió en els ovòcits de les femelles restringides. Aquest gen es un regulador clau en la maduració ovocitària, per aquest motiu, canvis en la seva expressió gen podrien explicar alguns dels problemes reproductius de les femelles. En el capítol 4 s'estudià si aquestes diferències a nivell ovocitari eren heretades per l'embrió i podrien causar la baixa fertilitat d'aquestes femelles. Encara que no se trobaren diferències en les taxes d'ovulació, recuperació embrionària i implantació, sí que es trobaren diferències en les pèrdues fetals i gestacionals, així com un menor creixement fetal en els embrions de les femelles provinents d'un règim alimentari restringit. Per això concloíem que l'estratègia nutricional emprada té conseqüències en el ovòcit (Capítol 3), i demostrarem que aquest canvis pareixen continuar en l'embrió, resultant en alteracions en pèrdues gestacionals i creixement fetal. El capítol final fou desenvolupat per evidenciar si els efectes reproductius i metabòlics observats en els capítols previs eren manifestats en les femelles que es troben en un sistema productiu tradicional de granja. Tot i que el resultats mostraren variacions en els nivells circulants de NEFAs i BOHB i pes corporal, no es trobaren diferències en el rendiment reproductiu global, en termes de fertilitat, prolificitat i productivitat. Els resultats obtinguts pareixen indicar que tot i que les diferències trobades a nivell ovocitari i embrionari amb un efecte significatiu en el desenvolupament i creixement fetal, amb el règim nutricional proposat no s'aconsegueix assolir millores en
Naturil Alfonso, C. (2016). EFFECT OF FEED RESTRICTION IN A RABBIT LINE SELECTED FOR GROWTH RATE ON REPRODUCTIVE PERFORMANCE: OVULATION INDUCTION, OOCYTE QUALITY, EMBRYONARY AND FETAL LOSSES [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/73065
TESIS

Styles APA, Harvard, Vancouver, ISO, etc.

12

Fougeyrollas, Romain. « Stratégies de reproduction et de dispersion chez deux termites humivores de Guyane, Embiratermes neotenicus et Silvestritermes minutus (Termitidae, Syntermitinae) ». Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1112/document.

Texte intégral

Résumé :

Chez les insectes sociaux, les reproductrices doivent faire face à un dilemme entre coûts et bénéfices de la reproduction asexuée et sexuée. Récemment, il a été montré que les reines termites pouvaient résoudre ce dilemme en optant pour l’utilisation alternée de la reproduction asexuée et sexuée, en produisant des femelles secondaires néoténiques par parthénogenèse, et les ouvriers, soldats et futurs essaimants par reproduction sexuée. Cette stratégie, appelée AQS pour « Asexual Queen Succession », a été décrite chez trois termites souterrains xylophages de la famille des Rhinotermitidae. Deux espèces humivores appartenant à la famille des Termitidae et particulièrement abondantes en forêt néotropicale, Embiratermes neotenicus et Silvestritermes minutus (Syntermitinae), semblaient être des nouvelles candidates pour cette stratégie, car elles présentaient des nids menées par de nombreuses femelles néoténiques. Pour confirmer cette hypothèse et déterminer l’origine génétique de ces femelles, des castes stériles et des futurs essaimants, nous avons développé une banque de microsatellites spécifiques pour E. neotenicus et S. minutus, et génotypé une dizaine de colonies du site de Petit Saut en Guyane, pour chaque espèce. Nous avons confirmé que les castes stériles et les imagos étai ent issus pour la très grande majorité de reproduction sexuée, alors que les femelles néoténiques étaient issues de parthénogenèse avec fusion centrale, un mécanisme différent de celui décrit chez les Rhinotermitidae. La reconstruction détaillée du cycle de vie de S. minutus nous a permis de conclure que l’AQS, au-delà des bénéfices communs à toutes les espèces i.e. la succession de plusieurs générations de reproductrices sans dilution de la participation génétique de la reine fondatrice, l’augmentation du potentiel reproductif de la colonie et la prévention de la consanguinité chez les castes stériles et les imagos, permettait à cette espèce d’investir dans un seul évènement massif d’essaimage pendant un cycle de vie très court. D’autre part, nous avons réalisé une analyse de structuration génétique des colonies et des populations d’E. neotenicus et de S. minutus dans le but de comprendre les conséquences de la dispersion, des modalités d’appariement et de la participation des différents reproducteurs sur la consanguinité des colonies et la potentialité de colonisation de ces espèces. Pour environ 40 colonies de chaque espèce, nous avons montré que les reproducteurs fondateurs étaient très majoritairement non apparentés, et une absence de viscosité à une échelle locale (1 à 11 km), suggérant une dispersion importante des essaimants. De plus, seule une très faible structuration génétique a pu être détectée sur l’ensemble du site d’échantillonnage, indiquant des flux de gènes peu contraints
In social insects, reproductive females have to face a dilemma between costs and advantages of asexual and sexual reproduction. Recently, termite queens were shown to be able to solve this dilemma by using alternatively asexual and sexual reproduction, with the production of secondary neotenic females by parthenogenesis, and workers, soldiers and future alate reproductives by sexual reproduction. This strategy, called AQS for Asexual Queen Succession, was described in three subterranean xylophagous termites of the Rhinotermitidae family. Two soil-feeding species belonging to the Termitidae family, and particularly abundant in Neotropical forest, Embiratermes neotenicus and Silvestritermes minutus (Syntermitinae), seemed to be new candidates for this strategy since they showed colonies headed by numerous neotenic females. In order to confirm this hypothesis and determine the genetic origin of these females, of sterile castes and future imagoes, we developed specific microsatellite libraries for E. neotenicus and S. minutus, and genotyped about ten colonies for each species, on the site of Petit Saut in French Guiana. We confirmed that sterile castes and imagoes were mostly produced by sexual reproduction, while neotenic females were produced by parthenogenesis with central fusion, a mechanism different from that described in Rhinotermitidae species. The detailed reconstruction of S. minutus life cycle allowed us to conclude that AQS, in addition to advantages common to all species i.e. succession of queen generations with undiluted genetic input of the foundress, multiplication of reproductive potential of the colony and prevention of inbreeding in sterile castes and dispersers, would allow this species to optimize a single dispersal event within a very short life cycle. Otherwise, we realized an analysis of colony and population genetic structuration of both species in order to understand consequences of dispersion, mating strategies and parental allocation on inbreeding and colonization abilities of both species. For about 40 colonies of each species, we showed that most of founding reproductives were not related, and absence of genetic viscosity at a local scale (1 to 11 km) suggesting long dispersal flights of alates. Furthermore, only a weak genetic structuration was detected, indicating unfettered gene flows on the sampling site

Styles APA, Harvard, Vancouver, ISO, etc.

13

Ilse, Breanne Rose. « Effects of Linseed Meal on Growth and Reproductive Performance in Ruminants ». Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/28744.

Texte intégral

Résumé :

Linseed meal (LSM) was fed to ovariectomized ewes exposed to estradiol 17-? (E2) implants over time, and LSM was supplemented to beef cows during late gestation and early lactation to evaluate the estrogenic potential of the phytoestrogen secoisolariciresinol diglycoside (SDG) found in LSM. Forty-eight ovariectomized ewes were fed a diet containing 12.5% LSM for 0, 1, 7, or 14 d and implanted with estradiol-17? (E2) for 0, 6, or 24 h before tissue collection. Uterine cellular proliferation, vascularity, and the expression of the angiogenic factors and their receptors were recorded. There was an interaction of LSM and E2 on uterine mass (P = 0.05). At 24 h of E2 exposure, proliferation was reduced (P < 0.001) when ewes were fed for 14 d compared to being fed 0 or 1 days. There was a LSM x E2 interaction (P ? 0.03) on VEGF receptor-2 (KDR) and hasicfihrohlast growth factor receptor (FGFR2) decreasing by 24 h E2 exposure. Exposure of LSM and E2 may impact the estrogenic response of sensitive tissue. Two studies were conducted to examine the effects of supplementing beef cows with LSM during late gestation or early lactation on calf growth and development. In Experiment 1, multiparous cows received either LSM or a control (CON) supplement (approximately 10% diet dry matter) for the last 60 d of gestation. Offspring weights, ADG, heifer age at puberty, conception percentage and steer carcass characteristics were recorded. In Experiment 2, multiparous cows received LSM or CON supplements (approximately 10% diet dry matter) during the first 60 d of lactation, and only heifer calf development performance was observed and recorded. Heifer calf weight, average daily gain, and attainment of puberty were assessed. For both experiments, birth weight, weaning weight and ADG were not affected (P > 0.31) by LSM supplementation. While final body weights were heavier (P = 0.04) for steer calves in Experiment 1, there was no effect (P = 0.09) of supplementation on carcass characteristics. In Experiment 1 and 2, attainment of puberty in heifer calves was not influenced (P > 0.58) by supplement type. Linseed meal supplementation during late gestation or early lactation does not appear to have a negative impact on calf growth, onset of puberty in heifer calves, or steer carcass quality, implicating that it may make a good supplement choice in cattle.

Styles APA, Harvard, Vancouver, ISO, etc.

14

Wuenschel, Jeffrey Carl Jr. « Effects of Feeding Supplemental Eicosapentanoic Acid and Docosahexanoic Acid to Beef Females on Reproductive Responses and Free Fatty Acids ». Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/34958.

Texte intégral

Résumé :

The objective of this study was to determine the effects of dietary supplementation of eicosapentanoic (EPA) and docosahexanoic acids (DHA) on reproduction in beef females. In experiment 1, cows (n = 31) were individually fed rumen protected fish meal (FM) or no fish meal (C) supplements. Estrus was synchronized and ovulation induced on d 37. Ovarian follicular growth and diameter were determined by ultrasound on d 35 and d 37. Serum progesterone (P4) profiles were analyzed on d 37 through d 52. On d 52 cows were cannulated, primed with estradiol-17β at -240 min, and stimulated to release PGF2α by oxytocin injection at 0 min with blood sampled every 15 min from -30 min to 240 min. Supplement type did not affect (P > 0.05) follicular diameter, follicular growth or P4 concentrations. In cows fed FM, prostaglandin metabolite (PGFM) concentrations tended (P ≤ 0.10) to be reduced at 0, 30, and 60 min. In experiment 2, crossbred heifers (n = 214) received FM or C concentrates with corn silage from 30 d before estrous synchronization until 14 d after artificial insemination (AI). Serum fatty acid profiles were determined in five heifers from each group . Estrus detection and AI were conducted from d 37 through d 39. Dietary treatment increased (P < 0.05) EPA and DHA concentrations. Dietary treatment did not affect estrus response or AI conception rates and pregnancy rate. Supplementation of FM increased EPA and DHA concentrations but did not affect reproductive factors.
Master of Science

Styles APA, Harvard, Vancouver, ISO, etc.

15

McNamara, Louise B. « Feeding and managing of the high performing sow in pregnancy and lactation, and growth and development of progeny ». Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558977.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

16

Omari, Mohamed [Verfasser]. « A Mathematical Model of Bovine Metabolism and Reproduction : Application to Feeding Strategies, Drug Administration and Experimental Design / Mohamed Omari ». Berlin : Freie Universität Berlin, 2019. http://d-nb.info/1200409051/34.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

17

Long, Amanda Marie. « Impacts of Flax on Female and Male Reproductive Traits When Supplemented Prior to Breeding in Sheep ». Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29877.

Texte intégral

Résumé :

Two experiments determined the effects of flaxseed supplementation on reproductive parameters in sheep. In experiment one, 240 multiparous Rambouillet ewes were assigned to one of two treatments: basal ration alone or basal ration with a Flaxlic® Sheep Tub offered over 35 days. Serum was collected weekly for progesterone (P4). Flaxseed supplementation did not improve progesterone concentration or reproductive parameters (P ≥ 0.26). In experiment two, 120 Rambouillet ram lambs were assigned to one of two treatments: basal ration alone or basal ration with a Flaxlic® Sheep Tub offered over 112 days. Scrotal circumference measurements, serum for testosterone, and semen were collected on day 84 and 112. Day effects were found for select semen measurements, testosterone, weight, and scrotal circumference (P ≤ 0.05). There was no effect of treatment on testosterone concentration (P = 0.99) or any semen quality characteristics (P ≥ 0.33). Overall, tub supplementation did not alter reproductive ability.

Styles APA, Harvard, Vancouver, ISO, etc.

18

Robinson, Julie A. « The effects of dietary molybdenum and sulfur on serum copper concentrations, growth and reproductive function in lambs ». Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/31319.

Texte intégral

Résumé :

Feeds often contain molybdenum (Mo) and sulfur (S) in excess of recommended allowances for adequate copper (Cu) absorption by ruminant livestock. Two randomized-block experiments were conducted using lambs given a cereal-based diet (90% of dry matter (DM) intake), containing 8 mg Cu, 0.7 mg Mo and 2.1g S per kg DM, that was either unsupplemented or supplemented with ammonium molybdate or sodium sulfate alone or in combination, to determine the effects of Mo, S and Mo+S on growth, hematology, serum Cu and Mo concentrations and reproductive function. Short term intake (4 weeks) by rams, aged 18 and 20 weeks, of 26 mg Mo alone or in combination with 2g S per kg DM, had no effect on growth, hematology or the concentration of total Cu in serum (TCu). However, supplemented groups had lower (P<0.05) concentrations of serum Cu soluble in trichloroacetic acid (TCA-Cu), but the group given Mo+S had the highest (P<0.05) concentration of serum residual Cu (RCu). Luteinizing hormone (LH) peak amplitude was affected by age*diet interaction (P<0.05), because of high amplitude LH peaks in the serum of lambs, aged 24 wks, given Mo alone. Testosterone serum secretory profiles did not differ among diet groups, but testosterone peak frequency was higher (P<0.05) for older ram lambs. Long term intake (32-39 wks) by ewe, ram and wether lambs (gonadal influence) of 12 mg Mo, or 2g S alone or combined per kg DM also had no effect on hematology or TCu. Food intake and liver weights were higher (P<0.05), but TCA-Cu was lower (P<0.05) for groups given S. Serum concentrations of total Mo (TMo) were higher (P<0.05) for Mo-supplemented groups, but RCu was highest only for the Mo+S group. Growth was affected by Mo*S*gonadal influence*time interaction (P<0.05); until autumn, the body weight of Mo-supplemented groups were higher than those of ram and wether lambs given Mo+S. Ovarian or testicular functions were delayed more severely for Mo- than Mo+S-supplemented groups. Mean concentrations of LH were affected by Mo*S*gonadal influence*time interaction (P<0.05); the mean LH values of Mo-supplemented ram and ewe lambs were higher than the Mo+S-supplemented group, whereas a reverse trend was observed for wether lambs. The amplitude of LH peaks was affected by Mo*S*gonadal influence*time interaction (P<0.05); for ram lambs, LH peak amplitude was higher for Mo than Mo+S-supplemented groups, whereas for wether and ewe lambs the reverse trend was noted. Mean concentrations of serum Cortisol and Cortisol peak amplitude were affected by Mo*S interaction (P<0.05); the mean Cortisol concentration and peak amplitude for the Mo-supplemented group were higher than those for the Mo+S-supplemented group. The frequency of LH and Cortisol peaks did not differ (P>0.10) among diet groups. In conclusion, Mo supplementation of cereal-based diets containing a high concentration of Cu did not adversely affect lamb growth. However, the effect of high dietary Mo on reproductive function appears to depend on the dietary level of S and the induction of high serum RCu (thiomolybdate). Further investigations on the effects of Mo and thiomolybdate on endocrine function may provide a nutritional basis for improving reproductive efficiency in ruminants.
Land and Food Systems, Faculty of
Graduate

Styles APA, Harvard, Vancouver, ISO, etc.

19

Vorsatz, Lyle Dennis. « Observations on the biology and seasonal variation in feeding of the East Coast redeye round herring (Etrumeus wongratanai) (Clupeiformes), off Scottburgh, KwaZulu-Natal, South Africa ». University of the Western Cape, 2016. http://hdl.handle.net/11394/5545.

Texte intégral

Résumé :

Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol)
The basic biology and ecology of Etrumeus wongratanai was investigated from samples of fish collected by jigging off Scottburgh, Kwazulu-Natal throughout 2014 and 2015. A total of 516 otoliths, 401 gonads, 140 stomachs and 163 samples of white muscle tissue was examined, and length and weight data of 3 637 fish caught between 2013 and 2016 was also analysed. Counts of annuli deposited on sagittal otoliths indicate that sampled E. wongratanai ranged from 0 to 3 y. (year/s) of age. Length-at-age for males (females) was estimated at 15.5 cm (16.2 cm) for 1 y. olds, 17.7 cm (17.4 cm) for 2 y. olds and 19.6 cm (18.8 cm) for 3 y. olds. The length at 50% maturity was estimated to be 15.6 cm for males, and 16.1 cm for females. Etrumeus wongratanai showed high gonadosomatic index values from June to December indicating that the breeding season lasts for 6 and 8 months for males and females, respectively, and that spawning takes place from the onset of winter to early summer. Condition factor was lowest in May through to August and increased from September. The low condition factor values from May through to August could be due to the physiological strain before and during the spawning season. Fish larvae were the most important food item in samples collected in summer, whereas eucalanids were the most important prey item in autumn and winter. Overall, large copepods were the dominant prey items in terms of frequency and importance. Stable isotope data suggests that there are gradual changes in the trophic level and diet of E. wongratanai as it increases with size, and whilst δ¹⁵N values differed between seasons δ¹³C did not. The results obtained here are compared with other species of Etrumeus, regionally and globally.
National Research Foundation (NRF) and ACEP Phulisa

Styles APA, Harvard, Vancouver, ISO, etc.

20

Hardy, Danita Sue 1957. « Reproductive success of round-tailed ground squirrels ». Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276596.

Texte intégral

Résumé :

I studied round-tailed ground squirrels (Spermophilus tereticaudus) to determine if presence of water or green vegetation significantly increased reproductive success. I compared the number of juveniles produced, body weights, and diets of squirrels during 1981-84 on 2 plots with green vegetation and no free water, on 3 plots with free water and no green vegetation, and 2 control plots. Reproductive success and body weights of adult and juvenile squirrels were significantly higher (P ≥ 0.001) on plots with green vegetation than on either watered or control plots. Body weights of squirrels on plots with water only and control plots were not significantly different (P ≥ 0.05). Adult squirrels without access to green vegetation during winter and spring failed to reproduce even though free water was readily available. Percent of diet overlap, diversity, and evenness of squirrel diets on control and watered plots were not significantly different. Green vegetation appeared to be the limiting factor for round-tailed ground squirrels.

Styles APA, Harvard, Vancouver, ISO, etc.

21

Foster, Gregory George. « Growth, reproduction and feeding biology of Turbo sarmaticus (Mollusca : Vetigastropoda) along the coast of the Eastern Cape Province of South Africa ». Thesis, Rhodes University, 1998. http://hdl.handle.net/10962/d1005391.

Texte intégral

Résumé :

Investigations were carried out on aspects of the biology of the vetigastropod Turbo sarmaticus. Studies included: 1) the distribution and standing stock of this animal at four sites along the coast of the Eastern Cape Province of South Africa; 2) the growth rate of animals on a wave-cut platform; 3) the reproductive cycle of an intertidal population; and 4) aspects of the feeding biology examining the ability of this mollusc to consume and digest six macroalgae, the influence of algal diet on growth rate and reproductive fitness and the polysaccharolytic activity of the digestive enzymes. On eastern Cape shores, T. sarmaticus had a size related distribution, with smaller animals being found towards the upper mid-shore and larger animals being found in a downshore direction. The mean shore densities of T. sarmaticus at three sites where exploitation of animals was minimal, were very similar (1.2 - 1.7 individuals/m²). The largest animals (up to 110 mm shell length) were found on an offshore island. This may have been a result of animals not being exploited, as well as a possible increase in primary productivity and food availability. The lowest density (0.2 individuals/m²) and animal size (<70 mm shell length) was recorded at a site (Kelly's beach - Port Alfred) where exploitation was more intense. It is probable that intense overexploitation was threatening the populations at this site. The growth rate of T. sarmaticus was determined by means of the von Bertalanffy growth model and expressed by the equation L[subscript]t = 81.07(l-e⁻°·⁵⁴⁴[superscript](t)). The initial growth rate of T. sarmaticus (up to ≈ 80 mm shell length) was similar on shores with different geomorphologies (i.e. boulder shores and wave-cut platforms). Growth rates of individuals were variable, which means that individuals within a population reached exploitable size (3 - 6 years old) and sexual maturity (1.5 - 2 years old) at different ages. Seasonality of reproduction of T. sarmaticus was determined using gonad index, egg diameters and spermatozoa content within the gonad. Turbo sarmaticus was dioecious and had a sex ratio in favour of males (1.2: 1). Animals attained sexual maturity at a size of about 52.5 mm shell length. There was little variation in the reproductive cycle over time with gametogenesis occurring from March/April until August/September, whilst maturity (Gonad Index = 15%) was maintained until the spawning event from December to March. After spawning the gonad regressed. Field and laboratory observations of the feeding biology of T. sarmaticus confirmed that this mollusc was a generalist grazer capable of consuming and digesting algae from the Rhodophyta, Chlorophyta and Phaeophyta. The consumption rates (juveniles: 1.45 - 9.50% body weight/day, adults: 1.06 - 6.08%) and digestibility (9 - 75% apparent dry matter) of six macroalgae was found to vary. For most algae, juvenile T. sarmaticus had higher consumption rates (1.6 - 2.8 times higher) and digestibility values (12 - 24% higher) than adults. It is suggested that consumption rates were dependent on the digestibility of the algae. In addition, it is suggested that the consumption rates of the different algae were not related to the nutritional content, but rather the energetic content of the algae. In both juvenile and adult animals, temperature had a positive influence on consumption rates, resulting in an increase at higher temperatures. However, in both juvenile and adult T. sarmaticus, algal digestibility was not affected by temperature. Finally, it was proposed that Viva rigida, Codium extricatum, Ecklonia radiata and Gelidium pristoides would provide the best nutritional value for growth and reproductive fitness in T. sarmaticus, whilst Jyengaria stellata and Corallina spp. would provide the poorest. Experiments on the effects of four algal diets on the biology of T. sarmaticus showed that the best growth rate (up to 13.8 mm shell length increase per annum), reproductive fitness (Gonad Index up to 33%) and energy levels (up to 4.76% glycogen in the foot) were achieved when T. sarmaticus was fed G. pristoides, U. rigid a or a mixed diet. Turbo sarmaticus fed Corallina spp. showed reduced growth (2.4 mm shell length increase), reproductive fitness (Gonad Index up to 4.4%) and energy levels (up to 3.42% glycogen in the foot). A study of the polysaccharolytic enzyme activity of T. sarmaticus indicated that this mollusc possesses enzymes that can, at least partially, digest most of the storage and structural polysaccharides found in the Chlorophyta, Rhodophyta and Phaeophyta. This further supported the findings that T. sarmaticus was a generalist grazer. Two levels of activity were detected: 1) high levels of enzyme activity (up to 328.2 Ilglmglmllhr)occurred on the storage polysaccharides that occur in the Rhodophyta and Chlorophyta, and 2) lower levels of activity were detected on the storage polysaccharides (up to 44.8 μg/mg/ml/hr) of the Phaeophyta and on all the structural polysaccharides tested (<45.5 μg/mg/ml/hr). It was suggested that T. sarmaticus did not rely heavily on structural carbohydrates as a source of carbon. Finally, the results of this study were discussed in relation to the future management of T. sarmaticus stocks, the possible role of this macro algal grazer in the intertidal zone and the effects of over-exploitation of this animal. The potential aquaculture of this mollusc was also addressed briefly.

Styles APA, Harvard, Vancouver, ISO, etc.

22

Mennigen, Jan A. « The Serotonergic System as a Target for Neuroendocrine Disruption in the Brain of Goldfish (Carassius auratus) ». Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19927.

Texte intégral

Résumé :

Serotonin stimulates reproduction and inhibits feeding/growth in the neuroendocrine brain of goldfish. The objective of this thesis is to study the effects of selective serotonin reuptake inhibitor pharmaceuticals (SSRIs) on these systems, as SSRIs, such as fluoxetine, are detected in effluent and bioconcentrate in the brain of wild fish. Genes of the serotonin system were cloned to identify molecular conservation, seasonal expression, and tissue distribution. The serotonin transporter, the target molecule of fluoxetine, was highly conserved and ubiquitously expressed in goldfish. Seasonal changes of hypothalamic gene expression of the serotonin transporter support a role in the seasonal modulation of both processes. Fluoxetine injection experiments were used to assess effects on reproductive endpoints and to identify molecular mechanisms in the neuroendocrine brain. Fluoxetine inhibited serum estradiol concentrations in female goldfish and decreased isotocin mRNA abundance in the hypothalamus and telencephalon. Isotocin injections stimulated circulating estradiol concentrations, providing a causal link. Evidence for an involvement of serotonin in isotocin regulation was investigated using immunocytochemistry and 5-HT1A receptor agonists and antagonists. A close proximity of serotonin fibers and isotocin cell bodies and fibers was found in the telencephalon and pituitary,respectively. Injection of a 5-HT1A receptor antagonist inhibited isotocin mRNA expression in the telencephalon. Identified gene targets were investigated in waterborne fluoxetine exposures,including environmental concentrations. Waterborne fluoxetine led to a reduction in basal and pheromone-stimulated milt volume in male goldfish. Gene expression evidence indicated a central inhibitory effect of fluoxetine through the decrease in mRNA abundance of follicle-stimulating hormone in the pituitary and isotocin in the telencephalon. Feeding rate and weight decreased in fluoxetine-injected goldfish, indicating an anorexigenic effect. Fluoxetine induced changes in the gene expression of the feeding peptides neuropeptide Y, corticotropin-releasing factor, and cocaine- and amphetamine-regulated transcript-I in the hypothalamus and telencephalon. Waterborne exposure to fluoxetine validated the anorexigenic effect in goldfish and was correlated with increased expression of corticotropin-releasing factor mRNA, an anorectic peptide. The thesis provides evidence for disrupting effects of fluoxetine on neuroendocrine control of reproductive function and feeding/growth in goldfish, partially at environmental concentrations. The thesis provides the framework for the investigation of existing aquatic contaminants which modulate the serotonin system.

Styles APA, Harvard, Vancouver, ISO, etc.

23

Kane, Erin Elizabeth. « Socioecology, stress, and reproduction among female Diana monkeys (Cercopithecus diana) in Cote d’Ivoire’s Tai National Park ». The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503076541553319.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

24

Datta, Tanmay. « Behavioural ecology of feeding and reproduction in openbill stork anastomus oscitans (Boddaert), at the Raiganj wild life sanctuary, Raiganj, West Dinajpur, India ». Thesis, University of North Bengal, 1992. http://hdl.handle.net/123456789/1003.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

25

Vaitilingon, Devarajen. « The biology and ecology of the echinoid Tripneustes gratilla (Linneaus, 1758) off Toliara (Madagascar) :feeding, reproduction, larval development, population dynamics and parasitism ». Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211163.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

26

Harrison, Timothy James Edward. « A curate's egg : feeding birds during reproduction is 'good in parts'. A study of blue tits Cyanistes caeruleus and great tits Parus major ». Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/590/.

Texte intégral

Résumé :

Food supplementation of birds in gardens is widespread and UK householders have recently been advised to supplement birds throughout the spring and summer. This coincides with reproduction of many avian species and supplementation with specific foods (e.g. live invertebrates) is encouraged to support breeding attempts in gardens. To investigate this further I mimicked food supplementation in gardens by providing two commercial bird foods (peanut cake and mealworms \(Tenebrio\) \( molitor\) to blue tits \(Cyanistes\) \(caeruleus\) and great tits \(Parus\) \(major\) breeding in woodland in central England from 2006 to 2008. Supplementation advanced laying and reduced the number of young fledged significantly in both species, but provisioning with mealworms during the nestling phase increased apparent survival of fledglings. Intriguingly, however, stable isotope analysis revealed that supplement use was insubstantial and similar between birds on supplemented and non-supplemented territories. Analyses of data from the British Trust for Ornithology’s Nest Record Scheme demonstrated strong parallels between findings of my field study and patterns of reproduction of blue and great tits in urban habitats across the UK. I discuss the implications of my findings, including the use of food supplementation in avian conservation and in pure scientific research, and I outline exciting future directions.

Styles APA, Harvard, Vancouver, ISO, etc.

27

Martineau, Jean Philippe. « Comparison of feeding inorganic sulfate trace minerals to partial substitution of organic trace minerals on gilt development, production and longevity and progeny growth performance ». Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27581.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

28

Msangi, Bakari Salum Juma. « Studies of smallholder dairying along the coast of Tanzania with special reference to influence of feeding and supplementation on reproduction and lactation in crossbred cows ». Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340029.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

29

Postuma, Felippe Aldert. « Population biology and behavioural aspects of the squid Doryteuthis plei (Blainville, 1823) in the northern coast of São Paulo, with emphasis on reproduction and feeding ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-13012016-143621/.

Texte intégral

Résumé :

This PhD thesis addresses several aspects of the biology and ecology of the squid Doryteuthis plei in the coast of São Paulo, SE Brazil, at both the population and individual levels. On the population structure of the exploited stock, it includes the patterns of reproductive activity, size-at-maturity, and biometrics of reproductive organs associated with squid size, as well as feeding habits and ontogenetic, sexual, and spatial-temporal shifts. Generalized Additive Models for Location, Scale, and Shape (GAMLSS) were used to identify such population patterns and spatial and temporal factors based on the particular small-scale fishery that targets the species around the São Sebastião Island. At the individual level, the study focused on behavioural traits in two periods of the life-cycle: (1) the reproductive phase, where the body patterns were described, generating a comprehensive ethogram for the species, and (2) the paralarval phase, where the development of swimming and predatory behaviours was detailed. Size-at-maturity was found to be 151-175 mm of mantle length (ML) for females, and 187-190 mm ML for males, that also showed the co-occurrence of two distinct maturation groups (Chapter 1). A significant peak of females gonad weight occurs in February and March especially in the island\'s South and Southeastern areas, and of males in March. An ethogram analysis showed 19 chromatic, 5 locomotor, and 12 postural components and behavioural sequences for the species, including agonistic, courtship, and mating behaviour (Chapter 2). Light chromatic components (clear and iridophore splotches) showed a longer duration than dark chromatic components, especially those associated with calm behaviour, more frequent in females. Males appeared more dedicated to disputes over resources and used fast miscellaneous visual signalling. In respect to feeding habits (Chapter 3), prey composition differed among sexes, size, maturity, and spatio-temporal pattern. Females do not stop feeding during sexual maturation and the amount of food increases with size. Cephalopods were significant preys for mature females, as well as fish and crustaceans to the largest females, while pelagic polychaetes were dominant prey for largest males. Observations and filming of D. plei paralarvae (Chapter 4) show a complex predatory behaviour on live preys, with different hunting types differing in speed and position. Aggressive intra-specific behaviour was found in the absence of prey when paralarvae show both a pursuit strategy and a rapid backward escape after attack. These findings contribute to better understand the population biology and behavior of the species and also in the future definition and guidance of fisheries management plans.
A presente tese aborda diferentes aspectos da biologia e ecologia da lula Doryteuthis plei na costa de São Paulo, SE do Brasil, tanto em nível individual quanto populacional. Com relação à estrutura populacional do estoque explorado, foram analisados padrões da atividade reprodutiva, tamanho de primeira maturação, morfometria dos órgãos reprodutivos associados às fases de desenvolvimento e também hábitos alimentares e mudanças ontogenéticas, sexuais e espaço-temporais. Modelos aditivos generalizados para localização, escala e forma (Generalized Additive Models for Location, Scale, and Shape - GAMLSS) foram utilizados com intuito de identificar padrões populacionais, espaciais e temporais baseados em desembarques da pesca de pequena escala em torno da Ilha de São Sebastiao. Em nível individual, o estudo abordou padrões comportamentais em 2 diferentes períodos do ciclo de vida: (1) fase de reprodução, onde padrões corporais foram descritos, tendo como resultado um abrangente etograma (2) fase paralarval, onde o desenvolvimento de comportamento natatório e predatório foram detalhados. O tamanho de primeira maturação foi estimado entre 151 e 175 mm de comprimento do manto (ML) para as fêmeas e entre 187 e 190 mm ML para os machos, também foi identificada a co-ocorrência de 2 grupos de maturação para os machos. (Capitulo 1). Um pico significativo com relação ao peso das gônadas foi identificado entre os meses de Fevereiro e Março para as fêmeas e em Março para os machos, especialmente nas áreas Sul e Sudeste da ilha. Uma análise dos comportamentos reprodutivos e dos padrões corporais, resultando em um amplo etograma, revelou 19 componentes cromáticos, 5 locomotores e 12 posturais, como também, sequências comportamentais para a espécie, incluindo comportamentos agonístico, de corte e acasalamento (Capitulo 2). Componentes cromáticos claros (manchas claras e irridóforos) apresentaram maior duração do que os componentes cromáticos escuros, particularmente aqueles relacionados ao comportamento calmo, mais frequente nas fêmeas. Machos aparentemente foram mais propensos a disputas por recursos usando sinalizações visuais rápidas e variadas. Em relação aos hábitos alimentares (Capítulo 3), a composição de presas diferiu entre sexos, tamanhos, maturidade e padrões espaço-temporais. As fêmeas não deixaram de se alimentar durante a maturação e foi observada uma relação positiva entre a quantidade de alimentos e o tamanho dos indivíduos. Pequenos cefalópodes, assim como peixes e crustáceos foram às presas mais significativas entre as fêmeas maduras, enquanto que para os machos foram os poliquetas. Através de observações e filmagens de paralarvas de D. plei (Capitulo 4), identificou-se um comportamento predatório complexo sobre presas vivas, com diferentes tipos de caça que diferem em velocidade e posição. Comportamentos agressivos entre indivíduos da mesma espécie (estratégias de ataque e fuga) foram identificados quando na ausência de presas. Estes achados contribuem para melhor compreender a biologia populacional, comportamento da espécie, e também na futura definição e orientação nos planos do manejo pesqueiro.

Styles APA, Harvard, Vancouver, ISO, etc.

30

Suranindyah, Yuni. « The effect of season and feeding management on production and reproduction of Etawah grade goats kept by smallholder farmers in an upland area of Yogyakarta province of Indonesia ». Thesis, University of Aberdeen, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408790.

Texte intégral

Résumé :

A series of studies aimed to improve reproductive efficiency and milk production by smallholders’ Etawah Grade goats. A survey was conducted from February to April 2000 in the villages of Girikerto, Girimulyo and Srandakan, where Etawah Grade goats were most concentrated. The aim of the survey was to know the contribution of Etawah Grade goat to the farmer income, evaluating factors, which were suspended to influence goat productivity, such as feed availability and goat management conducted in the villages. The result showed that Etawah Grade goat production in the villages was conducted in a small-scale farming enterprise, with the average number of 5 to 9 goats/farmer. In general, Etawah Grade goats contributed towards the income for the farmers by producing replacement stock, manure and milk. The agricultural and forages products varied from village to village. In the dry season feed was less available about 50% of that in the wet season (P<0.05). To solve the problem of feed shortage in the dry season, farmers either used by-products or purchased forage. The main reproductive problem in the villages was long period of post-partum anoestrus and low litter size, which might be associated with feed availability and management of weaning where the kids were separated from the doe after 3 to 5 months. An observation in an on-farm was conducted to see if seasons, by their effect on the availability, quality and consumption of feed or practical management, affected the reproductive performance, milk and kid production. Observation was conducted for the Etawah Grade goats under smallholder conditions during the dry (April to October 2000) and the wet seasons (November 200 to April 2001). Season was found to influence on the duration of post-partum anoestrus of goat in the villages (106 vs. 88 days, P<0.01) and birth weight of kids (3.8 vs. 3.2 kg, (P<0.05)). Litter size, kid mortality and weaning weight were not affected by season, but weaning weight varied by villages location (P<0.05).

Styles APA, Harvard, Vancouver, ISO, etc.

31

Denis, Jeremy. « Changements ontogéniques de la condition larvaire chez une espèce de poisson à reproduction hivernale, le hareng des Downs ». Thesis, Littoral, 2016. http://www.theses.fr/2016DUNK0431/document.

Texte intégral

Résumé :

La condition des larves de hareng des Downs durant la période critique a été caractérisée entre 2008 et 2015, en Manche orientale et dans la Baie sud de la Mer du Nord à partir des données collectées, durant la campagne International Bottom Trawl Surveys (IBTS). Tout d'abord, l'étude de la stratégie alimentaire, à partie de l'observation des proies dans les contenus digestifs par deux méthodes complémentaires (microscopie électronique et mesure de la fluorescence) a montré un changement de régime en fonction de la taille. Les larves inférieures à 13 mm avaient un régime omnivore très diversifié et composé de protistes et de petites proies zooplanctoniques, tandis que les larves plus grandes avaient un régime moins diversifié et composé principalement de plus grandes proies zooplanctoniques. En parallèle du changement de régime alimentaire, la combinaison de quatre indices de condition (taux d'ingestion, rapports ARN/ADN et ADN/C et otolithes) à l'échelle individuelle a également révélé un changement de l'état nutritionnel et de la croissance de ces larves. Les larves inférieures à 13 mm avaient une nutrition et une croissance soutenues, tandis que la croissance des larves plus grandes était faible. Ceci peut traduire un changement dans la stratégie d'allocation de l'énergie à partir de 13 mm, qui serait plus orientée vers du stockage que vers de la croissance. Ces changements ontogéniques dans la condition larvaire suggèrent que le changement de régime alimentaire qui s'opère à partir de 13 mm, pourrait constituer le coeur de la période critique pour les larves de hareng des Downs
The larval condition of Downs herring during the critical period was investigated between 2008 and 2015 in the eastern English Channel and Southern Bight of North Sea from data collected during the International Bottom Trawl Survey (IBTS). First, the study of the feeding strategy from gut contents analysis using two complementary approaches (electronical microscopy and measure of fluorescence) revealed a shift in the feeding diet occuring at a larval size of 13 mm. Smaller larvae had an omnivorous and a more diversified diet composed of numerous protists and small zooplanktonic preys whereas bigger larvae had a less diversified diet composed mainly of bigger zooplanktonic prey. Along with the diet shift, combination of four condition indices (ingestion rate, RNA/DNA and DNA/C ratios and otoliths) also revealed important changes in the nutritional status and growth of these larvae. Larvae smaller than 13 mm had a sustainable nutrition and growth whereas larger larvae depicted low growth rate. This could reflect a change in the energy-allocation strategy from a growth-oriented strategy towards a more storage-oriented strategy. These ontogenetic changes in the larval condition suggest that the diet shift occurring at 13 mm could constitute the core of the critical period for Downs herring larvae

Styles APA, Harvard, Vancouver, ISO, etc.

32

D'Angelo, Giulia Bagarolli 1982. « História natural das aves em um parque urbano no Sudeste do Brasil ». [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314736.

Texte intégral

Résumé :

Orientador: Ivan Sazima
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-24T19:31:06Z (GMT). No. of bitstreams: 1 D'Angelo_GiuliaBagarolli_M.pdf: 26225858 bytes, checksum: a6b9b77b3bd66a3d80fd5d3157a3fef5 (MD5) Previous issue date: 2014
Resumo: O processo de urbanização no Brasil aumenta rapidamente e as áreas verdes fornecem refúgio para a fauna local, na qual as aves são o elemento mais evidente. Aves são agentes importantes de dispersão e polinização, controle de pragas, além de ciclagem de nutrientes e adubação do solo, exercendo diversos serviços ambientais. Embora essas funções possam ser vistas como tendo pouca importância no ambiente urbano, aves apresentam grande mobilidade, o que significa que suas funções podem ser transportadas de uma área verde para outra. Estudamos a história natural das aves em um parque urbano em Campinas, São Paulo. Alimentação, reprodução e repouso foram os focos deste estudo, além de outras atividades como higiene e conforto. As atividades alimentares que observamos seguem, em linhas gerais, o que está relatado na literatura sobre aves brasileiras. Entretanto, observamos alguns fenômenos não relatados ou pouco conhecidos Associações alimentares de aves piscívoras seguindo lontras em atividade de caça não estavam relatadas para América do Sul. Disputa por área de caça entre fêmeas de biguatinga Anhinga anhinga foi outra novidade relacionada à atividade alimentar, assim como a predação de um bivalve asiático invasor por aves aquáticas. A inclusão de uma categoria de presa (répteis) na dieta do sabiá Turdus leucomelas também representou uma novidade. As atividades reprodutivas que observamos no parque também seguem, em linhas gerais, as informações disponíveis na literatura sobre aves brasileiras. Todavia, observamos eventos pouco conhecidos ou não relatados na literatura. A corte do urubu Coragyps atratus está relatada para a América do Norte apenas. Também pouco conhecida é a disputa territorial "simbólica" entre fêmeas do pica-pau Colaptes melanochloros, comportamento relatado para machos de outras espécies. Outra novidade foi a pressão de predação pelo lagarto Salvator merianae em ninhos de aves que nidificam no chão ou em vegetação próxima a margem de lagoa. Atividades de higiene e conforto são bem conhecidas e ilustradas na literatura e acreditamos que não tenhamos observado algum comportamento de higiene e conforto que não esteja relatado, ainda que de passagem, para as aves brasileiras. Estudos sobre história natural de aves proporcionam um conhecimento mais adequado das relações entre as aves, o ambiente urbano e a população humana. Em parques e áreas verdes, as aves representam uma parcela de lazer para a população urbana. O número de observadores de aves aumenta no Brasil e, paralelamente, há uma valorização da conservação ambiental. Portanto, estudos em parques urbanos resultam em conhecimento sobre a avifauna, além de valorizar as áreas verdes e popularizar o conhecimento sobre as aves e a sua importância biológica
Abstract: The urbanization process in Brazil is quickly changing the landscape and so called green areas provide refuge for the local fauna, of which birds are the most conspicuous part. Birds are important agents of plant dispersal and pollination, pest control, as well as nutrient cycling and soil fertilizing, which result in ecosystem services. Although these functions may be viewed as having little or no importance in the urban landscape, birds are highly mobile and their functions may connect several green areas. We studied the natural history of birds in an urban park in Campinas, São Paulo, Southeastern Brazil. We focused on feeding, reproducing, and resting, besides preening and comfort activities. In general, feeding activities we observed followed what is published about Brazilian birds. However, we observed a few little known or until recently unpublished events. Feeding associations of piscivorous birds following foraging otters were unreported for South America. Contests for hunting area between females of the darter Anhinga anhinga was another novelty related to feeding activity, as well as the predation of an Asiatic invasive clam by water birds. Predation of reptiles by the thrush Turdus leucomelas was also a novelty. In general, reproductive activities we observed followed what is published for Brazilian birds. However, we observed a few little known or unpublished behaviors. For example the courtship of the vulture Coragyps atratus is reported for the North America only. Also little known is the territorial "symbolic" contest between females of the woodpecker Colaptes melanochloros, a behavior reported for males of other species. Another novelty was the predation pressure on birds that nest on the ground or bank vegetation by the large lizard Salvator merianae. Preening and comfort behaviors are well known and illustrated in literature and we believe that we did not record any behavior that is not reported in the literature on Brazilian birds, even if en passant. Studies on natural history of birds provide a better knowledge on the relationships between the birds, the urban landscape, and the human population. In urban parks and green areas, birds are part of leisure activities for urban people. The number of birdwatchers is increasing in Brazil and, at the same time, there is a growing awareness of environment conservation among people who are in contact with nature. Therefore, studies on natural history of birds in urban parks and other green areas result in knowledge of the bird fauna, besides increasing the intrinsic value of these environments and making available details of the life of birds and their biological significance
Mestrado
Biodiversidade Animal
Mestra em Biologia Animal

Styles APA, Harvard, Vancouver, ISO, etc.

33

Amir, Omar A. « Biology, ecology and anthropogenic threats of Indo-Pacific bottlenose dolphins in east Africa ». Doctoral thesis, Stockholm : Department of zoology, Stockholm university, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-34472.

Texte intégral

Résumé :

Diss. (sammanfattning) Stockholm : Stockholms universitet, 2010.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 4: In progress. Paper 5: Submitted.

Styles APA, Harvard, Vancouver, ISO, etc.

34

Hajizadeh, Kapateh Ali. « Effect of dietary lipid sources on the reproductive performance of Nile tilapia Oreochromis niloticus ». Thesis, University of Stirling, 2009. http://hdl.handle.net/1893/2023.

Texte intégral

Résumé :

Traditionally, fish oil (FO) has been used extensively in aquafeeds. The stagnation in global fish oil production coupled with an increased demand for its use in aquaculture feeds, especially salmonid feeds, has greatly inflated fish oil prices. Therefore, in order to sustain the rapid growth of the tilapia industry, the dependence on these commodities in feeds should be reduced through use of cheaper and more sustainable sources of dietary lipids, such as palm oil. This study therefore investigated several, previously poorly understood, effects of palm oil on reproductive performance of the commercial tilapia species, Oreochromis niloticus; which currently ranks as second most popular species in world aquaculture. In the present study broodstock were fed on experimental diets at full and half ration regimes throughout their entire life cycle from exogenous feeding. Studies were conducted in standardised and controlled hatchery conditions, thereby reducing the potential influence of environmental variations. First feeding O. niloticus fry were fed on four diets, cod liver oil (D 1), palm oil (D 2), mixed palm and cod liver oil (D 3) (9:1 ration) and a commercial trout diet as control (D 4) (Skretting, U.K.) on a reducing ration based on fish size. The present study investigated the effect of dietary lipid sources on (1) growth performance, (2) biochemical composition of eggs (total lipid and fatty acid composition), (3) morphological parameters of eggs (total and relative fecundity, egg size, egg weight and EW:BW), (4) larval quality (larval length and weight) and (5) oocyte recruitment and its associated sex steroid hormones. Experimental diets and feeding ration significantly influenced (p<0.05) the growth performance over a period of 120 days. Total lipid and fatty acid composition of eggs originating from broodstock fed on palm oil, mixed palm and cod liver oil (9:1) or a control diet were not significantly different (P>0.05) when fed at either full (3% BWday-1) or half ration (1.5% BWday-1). The present study, however, confirmed that fatty acid composition of fish eggs reflected the fatty acid composition of the diet, although specific fatty acids were selectively utilized or retained in the eggs. The mean inter-spawning interval (ISI) increased with increasing fish size and averaged 14, 19 and 24 days for fish fed on palm oil, mixed palm and cod liver oil or control diets, respectively. The shortest ISI observed was 7 days for fish fed a palm oil diet. Total fecundity ranged from 660 - 820 eggs/clutch. Mean total fecundity was 750, 820 and 660 eggs/clutch for fish fed a palm, mixed palm and cod liver oil or a control diet, respectively, but these differences were not significant (P>0.05). However, relative fecundity and egg weight to body weight rates as a percentage (EW: BW) were found significantly differ (p<0.05) between fish fed the control diet and experimental diets. Mean egg diameter (2.2 mm) was not significantly influenced (p>0.05) by experimental diets. The egg volume, egg dry and wet weight, fertilisation and hatching rate were also not significantly different between fish fed the experimental diets. Oocyte development was classified into distinct stages based upon oocyte size, biochemical properties and structure. The recrudescence to these stages was not significantly influenced by broodstock fed experimental diets either at full or half ration. Steroid hormones and histological analyses provided valuable data concerning the oocyte development and recruitment in this species. Levels of 17ß-oestradiol (E2) and testosterone (T) peaked within 6 days of spawning, suggesting that vitellogenesis began as early as day 2 or 3 post-spawning. By day 6, ovaries were dominated by large late-vitellogenic/maturing oocytes (stages 6 & 7) occupying about 70% of the ovary. Gonadosomatic index (GSI) reached maximal levels by day 6. It is suggested that pre-vitellogenic oocytes are recruited into vitellogenic growth immediately after spawning and complete vitellogenesis on day 6 post-spawning. Finally, the present study investigated the effect of food restriction at two rations (full and half) on broodstock reproductive performance. Oreochromis niloticus were rationed from first feeding and throughout their life-cycle. The dietary regime, full ration (3%) and half ration (1.5%), influenced fish size but despite this variation no significant differences (p>0.05) were detected in total lipid and fatty acid composition in the eggs, total fecundity, egg diameter, total egg volume and larval size. These results suggested that despite large differences in food availability throughout their life cycle, investment in reproduction had remained remarkably consistent. It appeared that during food restriction, O. niloticus sacrificed body weight and growth so as to maintain reproductive investment. In summary, this study provides valuable information using a novel experimental design on the effects of dietary lipid sources on reproductive performance of female O. niloticus. Substituting palm oil for fish oil as the dietary lipid source and reducing ration by half (1.5% BWday-1) had no significant effect on reproductive performance. Therefore it is suggested that under controlled conditions, lipids of non-marine origin, such as palm oil, can be successfully substituted for broodstock diets. Halving feed requirement should also increase profitability of seed production. KEYWORDS: Tilapia; O. niloticus; palm oil; diet; fecundity; spawning periodicity; oocyte recruitment; reproductive performance.

Styles APA, Harvard, Vancouver, ISO, etc.

35

Jin, Shiyu. « Ecologie de la reproduction et de l'alimentation de l'écrevisse rouge des marais, Procambarus clarkii (Girard, 1852) en Chine ». Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30114.

Texte intégral

Résumé :

L'aquaculture s'est développée rapidement ces dernières années et est devenue l'un des principaux contributeurs à l'approvisionnement alimentaire dans le monde. En effet, l'immense pression de pêche exercée sur les populations sauvages et d'élevage entraîne progressivement l'épuisement des stocks. Le nombre limité de larves fournies pour l'aquaculture et des stratégies d'alimentation non optimales (par exemple un apport élevé en aliments artificiels) entravent le développement d'une industrie aquacole efficace. Une gestion plus durable de l'aquaculture nécessite maintenant une amélioration de la gestion des pêches, de la reproduction artificielle et des stratégies d'alimentation. Dans cette thèse, nous nous sommes intéressés à trois questions principales : (1) quelle est la dynamique de population et l'écologie de la reproduction des écrevisse de Louisiane en bassins articifiels ? (2) Quelles sont les temperatures optimales pour permettre une reproduction artificielle et un développement embryonnaire optimal chez cette espèce ? (3) Quelle est la quantité et la composition alimentation optimale en bassin pour assurer une bonne croissance des juvéniles en générant un minimum de déchets ? Cette thèse repose sur plusieurs étapes et approches expérimentales. Pour la question (1) nous avons étudié la dynamique de population et lareproduction de l'écrevisse de Louisiane (Procambarus clarkii) en évaluant la croissance, les taux de mortalité et le taux d'exploitation de populations cultivées en bassins commerciaux, ainsi que différents indices reproducteurs (GSI, HSI, développement ovarien et fécondité). Les résultats montrent quela ponte de P. clarkii se déroule en Chine de septembre à novembre, avec une fécondité moyenne de 429 ± 9 œufs par femelle, avec deux recrutements par an. Il y avait cinq cohortes de croissance at les résultats montrent que les mâles P. clarkii étaient surexploités. Nous suggérons donc de réduire l'intensité de la pêche sur les écrevisses immatures et d'éviter la sélection des mâles en période de reproduction afin d'améliorer la durabilité globale des populations commerciales de P. clarkii. Pour la question (2), nous avons testé les effets de la température de l'eau sur les performances de reproduction et de développement embryonnaire de P. clarkii. Les résultats montrent que la manipulation de la température de l'eau est un moyen efficace d'induire le frai chez les femelles et d'optimiser le développement embryonnaire pour améliorer la production larvaire, avec des températures optimales de 21 - 25°C et 25°C, respectivement. Nous avons élaboré un modèle de développement dépendant de la température pour P. clarkii, exprimé en D (durée du développement, jours) = 3140837 (T-2.03) -3.76. Enfin, pour la question (3), nous avons testé les effets de la réduction des niveaux d'alimentation et des niveaux de protéines sur les performances de croissance et la composition musculaire de P. clarkii juvéniles ayant accès à des aliments naturels tels que les macrophytres Hydrilla verticillata dans des mares commerciales Les résultats montrent que la réduction des quantités de nourriture artificielle à 60% de satiété ou à 26% de protéines n'affectait pas de manière significative les performances de croissance et la composition musculaire des écrevisses. En effet, une analyse des isotopes stables suggère que les écrevisses compensent la réduction de nourriture artificielle ou de protéines en consommant plus de macrophytes naturels H. verticillata facilement disponibles. Cette thèse propose donc de nouvelles alternatives à la reproduction artificielle traditionnelle en ajustant le prélèvement d'adultes, en manipulant la température de culture et en affinant les stratégies d'alimentation, afin de réduire les coûts de production tout en améliorant la productivité et la durabilité de l'aquaculture d'écrevisses
Aquaculture has developed rapidly in recent years and has become one of the primary contributors to food supply worldwide. However, the immense fishing pressure on wild and commercial-farmed populations has caused population depletion. Furthermore, limited juvenile crayfish production for aquaculture and suboptimal feeding strategies (such as high inputs of artificial diets) has hindered the development of sustainable aquaculture industry. Improving fisheries management is now necessary, based on a better scientific knowledge of population dynamics, reproductive ecology, and optimal feeding strategies, in particular by determining optimal environmental parameters for reproduction and refining artificial diets inputs. In this thesis, we focused on three main questions. First (1) what is the population and reproduction dynamics of adult crayfish living in commercial ponds and how should we adjust the aquaculture management? Second (2) what are the optimal temperatures for artificial reproduction and embryonic development? And third (3) what are the optimal levels of feeding and protein composition of artificial food for crayfish growth? For the first question (1), we studied the population dynamics and reproductive pattern of red swamp crayfish (Procambarus clarkii) by estimating growth, mortality rates, and exploitation rate of a commercial population, as well their reproductive parameters (GSI, HSI, ovarian development, and fecundity). Results showed that spawning activities took place from September to November, with a mean fecundity of 429 ± 9 eggs per female, and two recruitments yearly. There were five growth cohorts and male P. clarkii were overexploited. We thus suggest reducing fishing intensity on immature crayfish and avoid sex selection during the reproductive period to improve the overall sustainability of commercial P. clarkii populations. For the second question (2), we experimentally tested the effects of water temperature to improve reproductive outputs and embryonic development. Results showed that manipulating water temperature was an effective way to induce spawning in females and optimize embryonic development to improve juvenile production, with optimal temperatures of 21 - 25°C and 25°C, respectively. We also built a temperature-dependent developmental model for P. clarkii, D (developmental time, days) = 3140837(T-2.03)-3.76. Finally, for the third question (3), we experimentally tested the effects of five different feeding levels and reduced dietary protein levels (2 experiments) on growth performance and muscle composition of juvenile P. clarkii with natural food Hydrilla verticillata. Results showed that reducing the amounts of an artificial diet to 60% satiation and/or reducing the dietary protein level of the artificial diet to a level of 26% did not significantly affect the growth performance and muscle composition of P. clarkii. Stable isotope analysis suggested that crayfish switched diets to easily available H. verticillata when feeding levels or dietary protein levels decreased. This thesis thus explored new alternatives to traditional crayfish aquaculture by adjusting fishing effort and season, manipulating crayfish culture temperature, and refining feeding strategies to reduce production costs while improving the productivity and sustainability of crayfish aquaculture

Styles APA, Harvard, Vancouver, ISO, etc.

36

Trent, Jewel Andrew. « Ecology, Habitat Use, and Conservation of Asiatic Black Bears in the Min Mountains of Sichuan Province, China ». Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/33560.

Texte intégral

Résumé :

This project was initiated in an attempt to address the paucity of data on Asiatic black bears (Ursus thibetanus) in Mainland China. Field work was carried out from May 2004 – August 2006 within the Tangjiahe National Nature Reserve in northwestern Sichuan Province, China. Initial methodology relied on trapping and GPS radio-collaring bears, but due to extreme difficulty with capturing a sufficient sample size, I expanded the study to include reproduction, feeding analysis from scats and sign, and occupancy modeling from sign surveys. I documented the home ranges of an adult female (100% MCP = 107.5km2, n=470 locations) and a sub-adult female (100%MCP = 5.9km2, n=36 locations) Asiatic black bear. I also documented two birthing occasions with a total of four male cubs produced and eight bear den sites. I collected feeding data from 131 scat samples and 200 bear sign transects resulting in 50 identified food items consumed by Asiatic black bears. I also employed the program PRESENCE to analyze occupancy data using both a standard grid repeated sampling technique and an innovative technique of aging bear sign along strip transect surveys to represent repeated bear occupancy over time. Conservation protection patrolling and soft mast were shown to be the most important factors determining the occupancy of an area by Asiatic black bears in Tangjiahe Nature Reserve, Sichuan Province, China.
Master of Science

Styles APA, Harvard, Vancouver, ISO, etc.

37

Costi, Roberta Burkhardt. « Mulheres idosas participantes de um programa de exercícios-analisando o consumo alimentar e o índice de massa corporal (IMC) em relação ao desempenho no teste de caminhada de seus minutos ». Master's thesis, Instituições portuguesas -- UP-Universidade do Porto -- -Faculdade de Ciências do Desporto e de Educação Física, 2001. http://dited.bn.pt:80/29550.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

38

Puranen, Vasilakis Mikaela. « A comparison between the effects of polylactic acid and polystyrene microplastics on Daphnia magna ». Thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-145370.

Texte intégral

Résumé :

The effects of microplastics on zooplankton are an increasing environmental concern. Both primary microplastics that are produced as constituents of cosmetic products, as well as secondary microplastics that are formed by degradation of larger plastic debris, are ubiquitous in aquatic environments. Today, primary microplastics are being phased out and replaced by plant-derived bioplastics. Whether these new materials have similar effects as oil-based microplastics on animals is currently unknown. Here, we compare the effects of secondary microplastic exposure to Daphnia magna, using polylactic acid (PLA) as a representative for bioplastics and polystyrene (PS) for oil-based plastics. To increase the ecological relevance of our tests, we also provided treatments where the particles were coated with bovine serum albumin (BSA) as a means to simulate the coating of biofilms which readily form on particles under natural conditions. Furthermore, to be able to differentiate the effects of general particles from those specific to microplastics, kaolin clay was used as a control treatments, as well as one treatment containing only algae. The objectives were to test the influence of particles on feeding rates, reproduction and growth. PS caused a higher mortality, decreased feeding rate and reproductive output, while PLA and kaolin did not produce any negative effects. BSA did not have a significant effect on reproduction or growth. However, a decrease in reproduction was observed in the plastic treatments. Degradation of PS into styrene monomers is suggested as a possible explanation for the observed toxicity and effects on life history parameters.

Styles APA, Harvard, Vancouver, ISO, etc.

39

Gökce, M. A. « Reproductive biology and feeding ecology of gurnards ». Thesis, Swansea University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637060.

Texte intégral

Résumé :

Tub (Trigla lucerna), Red (Aspitrigla cuculus) and Grey (Eutrigla gurnardus) gurnards exhibit a distinct reproductive cycle. The spawning periods of Tub, Red and Grey gurnard occur from March to July, February to August and February to July respectively. The spawning periods of all three species commence at a minimum sea temperature (approximately 8°C) with the onset of increasing daylength and cease with the onset of decreasing daylength. A highly significant correlation was found between absolute fecundity and total weight of all three species. The relative fecundities of the three species are similar, 234-414 per g body weight for Tub, 271-377 per g body weight for Red and 306-551 per g body weight for Grey gurnard. The ovaries of Tub, Red and Grey gurnard can be characterised as asynchronous ovaries. Histological and ultrastructural studies reveal that these three species have similar oocyte development patterns. There was no hiatus or gap observed in the recruitment of oocytes from the PGP into the SGP or between the different oocyte developmental stages. Two types of yolk inclusions are formed: Lipid vesicles which appear in the mid and outer cortex indicate the initiation of the SGP and later migrate to the inner cortex and coalesce into a single lipid mass and protein yolk granules which initially form as small granules in the outer cortex of the cytoplasm. On maturation they fuse into large granules packing the cortical cytoplasm. In all three species Crustaceans and Teleosts are the preferred prey. Red gurnard had the broadest diet, Grey gurnard had the narrowest. The lowest diet overlap was observed between Grey and Red and the highest between Grey and Tub gurnards. This considerable diet overlap occurring between Grey and Tub gurnard may lead to interspecific competition for food.

Styles APA, Harvard, Vancouver, ISO, etc.

40

Souza, Ursulla Pereira [UNESP]. « Biologia e ciclo de vida de Astyanax cf. scabripinnis paranae Eigenmann, 1914 (Characidae, Tetragonopterinae), no Ribeirão Grande, Parque Estadual da Serra do Mar, núcleo Santa Virginia, SP ». Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/106542.

Texte intégral

Résumé :

Made available in DSpace on 2014-06-11T19:35:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-02Bitstream added on 2014-06-13T20:46:50Z : No. of bitstreams: 1 souza_up_dr_rcla.pdf: 976950 bytes, checksum: b3702264109c8e9210e947b1e4df6b90 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo geral do presente estudo foi analisar a biologia e o ciclo de vida de Astyanax cf. scabripinnis paranae no ribeirão Grande, um riacho de cabeceira localizado no Parque Estadual da Serra do Mar (PESM), Núcleo Santa Virgínia, SP. Os exemplares foram coletados mensalmente de janeiro a dezembro em 2004 e 2006, utilizando-se redes de espera, redinha de mão e covo. Foram coletados dados de temperatura da água, oxigênio dissolvido e pH. Dados de pluviosidade, umidade relativa e temperatura do ar foram obtidos junto à Estação Meteorológica do PESM. Os peixes foram fixados em formalina a 10% e conservados em álcool 70%. No laboratório foram mensurados quanto ao comprimento total e padrão, peso e registrados os graus de repleção estomacal, de gordura acumulada, o sexo e os estádios de maturação gonadal. As correlações entre as variáveis ambientais e os meses de coletas foram verificadas por uma análise de componentes principais, que indicou uma separação entre períodos mais chuvosos (outubro a abril) e menos chuvosos (maio a setembro). A dieta foi analisada pelo grau de preferência alimentar. Diferenças no consumo de itens autóctones e alóctones e possíveis mudanças ontogenéticas ao longo do desenvolvimento da espécie foram verificadas por uma análise de correspondência. Para o estudo da reprodução foram analisadas as variações nos estádios de maturação, relação gonadossomática, grau de gordura acumulada, condição corporal, fecundidade e tipo de desova. O comprimento médio de primeira maturação gonadal foi estimado pelo ajuste não-linear e a condição corporal foi avaliada por modelos de análise de covariância. A fecundidade foi estimada pelo método volumétrico e relacionada ao comprimento padrão, ao peso total, ao peso das gônadas e à relação gonadossomática. No estudo do crescimento, a separação das coortes...
The present study aimed to analyze the biology and ecology of Astyanax cf. scabripinnis paranae in the Ribeirão Grande, a headwater stream located in the Parque Estadual da Serra do Mar (PESM), Núcleo Santa Virgínia, SP. The fishes were sampled monthly from January to December in 2004 and 2006, using gillnets, sieves and funnel traps. Temperature, dissolved oxygen and pH of the water were measured. Pluviometric data, relative humidity and temperature of the air were obtained in the Meteorological Station of PESM. The fishes were fixed in 10% formalin and conserved in 70% alcohol. In the laboratory they were measured as for the total and standard length, weighed and registered the degrees of stomach repletion, of accumulated fat, the sex and the stadiums of gonad maturation. The correlation structure among the environmental variables measured in the sampling collections was verified by a principal components analysis (PCA), which indicated a separation among rainier (October to April) and the less rainy periods (May to September). Differences in the consumption of autochthonous and allochthonous items and possible ontogenetic changes along the specimens development were verified by a correspondence analysis (CA). For the study of the reproduction the variations were analyzed at the maturation stadiums, gonadossomatic relationship, degrees of accumulated fat, corporal condition, fecundity and spawning type. The mean length of first gonad maturation was assessed by a no-linear adjustment. The corporal condition was evaluated by analysis of covariance. The fecundity was estimate by the volumetric method and related to the standard length, to the total weight, to the gonad weight and to the gonadossomatic relationship. In the study of the fish growth, the cohorts’ separation and their mean lengths were obtained using the package MIXDIST and the Bhattacharya method... (Complete abstract click electronic access below)

Styles APA, Harvard, Vancouver, ISO, etc.

41

Chinnery, Fay Elizabeth. « The feeding and reproductive strategies of Acartidae in Southampton Water ». Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252444.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

42

ROCHA, Bruno César Luz. « Habitats adequados e aspectos ecológicos do tubarão-baleia (Rhincodon, typus Smith 1828) no Oceano Atlântico Sudoeste e Equatorial ». Universidade Federal da Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18654.

Texte intégral

Résumé :

Submitted by Rafael Santana (rafael.silvasantana@ufpe.br) on 2017-04-26T19:32:19Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_B_Macena_Full_Tubaleia_oficial_FINAL_BIB.pdf: 3006322 bytes, checksum: 3a1ffaf6152b8966edc8c3989913e65f (MD5)
Made available in DSpace on 2017-04-26T19:32:19Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_B_Macena_Full_Tubaleia_oficial_FINAL_BIB.pdf: 3006322 bytes, checksum: 3a1ffaf6152b8966edc8c3989913e65f (MD5) Previous issue date: 2016-12-01
CNPQ
Compreender detalhadamente a história de vida do tubarão-baleia é fundamental para assegurar a sua conservação. No entanto, apesar da espécie possuir distribuição circumglobal e ser relativamente bem estudada entre os elasmobrânquios, ainda existe uma grande escassez de informações relacionadas a muitos dos seus aspectos ecológicos e biológicos em todo o mundo, principalmente no que diz respeito aos seus movimentos migratórios e ciclo reprodutivo. No Oceano Atlântico, particularmente, a espécie vem sendo investigada majoritariamente no Golfo do México/ Mar do Caribe, permanecendo uma grande lacuna para o restante dessa bacia oceânica. O presente estudo representa a primeira iniciativa de investigação da distribuição espacial do tubarão-baleia em escala oceânica no sudoeste do Atlântico baseada em registros de ocorrências na costa do Brasil, além de ter sido o primeiro trabalho também sobre o rastreamento de tubarões-baleia na região equatorial. Com o objetivo de complementar o conhecimento acerca da distribuição geográfica e movimentação do tubarão-baleia nas regiões sudoeste e equatorial do oceano Atlântico, foram empregadas técnicas modernas de modelagem ecológica e rastreamento via satélite, além da utilização do método tradicional de censo visual para identificação de aspectos populacionais no Arquipélago de São Pedro e São Paulo (ASPSP). Primeiramente, foram realizadas predições referentes à distribuição espacial de habitats adequados para alimentação e inferências sobre a influência de variáveis ambientais específicas para ocorrência do tubarão-baleia na costa do Brasil/ sudoeste do oceano Atlântico. Em seguida, a sazonalidade, a abundância relativa e a estrutura populacional dos tubarões-baleia que visitam o ASPSP foram investigadas, incluindo inferências acerca da importância de ecossistemas insulares oceânicos para a parcela madura da espécie. Por fim, na terceira parte da Tese, os deslocamentos horizontais e verticais de tubarões-baleia marcados com transmissores via satélite no ASPSP foram descritos e o comportamento de mergulho avaliado com relação a fatores biofísicos e ambientais específicos. Os resultados obtidos no presente estudo são relevantes não somente para a conservação do tubarão-baleia, mas para o ecossistema marinho na costa do Brasil, de uma forma geral, posto que o mapeamento de habitats ideais para alimentação da espécie também serve para identificar áreas ecologicamente importantes para outras espécies. Ademais, a identificação do ASPSP como uma área importante para a parcela adulta dos tubarões-baleia ressalta sua importância ecológica no ciclo de vida da espécie, destacando a necessidade de se envidar maiores esforços para a conservação do local.
Understanding the life history of the whale shark is fundamental to assure its conservation. However, in spite of the circumglobal distribution of the species and the fact that it is relatively well studied among elasmobranchs, there is still a serious lack of information concerning its biology in the entire world, mainly regarding its migratory movements and reproductive cycle. In the Atlantic Ocean, particularly, the whale sharks have been predominantly studied in the Gulf of Mexico/Caribbean Sea, with a big gap still remaining for the rest of this ocean basin. Aiming to help to fill this gap on geographical distribution and movement patterns of whale sharks in the Equatorial and Southwest Atlantic regions, modern techniques of ecological modelling and satellite tracking were used, in addition to the use of scientific traditional method of visual census to describe the population aspects of the species in the archipelago of São Pedro and São Paulo (ASPSP). Firstly, geographical predictions of suitable habitats for whale shark feeding and inferences of the influence of specific environmental variables on the occurrence distribution in the Brazilian coast/southwestern Atlantic Ocean were conducted to describe the potential spatial distribution of the species. Then, the seasonality of occurrence, relative abundance and population structure of the whale sharks visiting the ASPSP were investigated, including a discussion regarding the importance of the insular oceanic ecosystems to the mature portion of the species. Finally, in the third part of the thesis, the horizontal and vertical displacements of whale sharks satellite tagged off ASPSP were described and the diving behavior assessed in relation to specific biophysical and environmental factors. The present study represents the first oceanic-scale spatial distribution investigation effort in the southwest Atlantic on whale shark presence records from the Brazilian coast, besides of being the first study using satellite tracking on the species in the equatorial Atlantic as well. The results presented here are of great relevance not only for the whale shark conservation but also for the Brazilian marine ecosystem, as the mapping of suitable feeding habitats could contribute to the identification of areas of ecological importance to other marine species. Moreover, the identification of the ASPSP as an important area for the mature part of whale shark populations highlights its ecological relevance on the species life cycle, emphasizing the need of increasing the conservation efforts in this habitat.

Styles APA, Harvard, Vancouver, ISO, etc.

43

Fischer, Luciano Gomes. « Distribuição, biomassas e ecologia de Macrouridae (Teleostei, Gadiformes) no talude continental do sul do Brasil, com ênfase em Coelorinchus marinii hubbs 1934 e Malacocephalus occidentalis Goode & ; Bean 1885 ». reponame:Repositório Institucional da FURG, 2012. http://repositorio.furg.br/handle/1/4053.

Texte intégral

Résumé :

Tese(doutorado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2012.
Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-10-11T16:45:36Z No. of bitstreams: 1 Luciano.pdf: 10791164 bytes, checksum: abbbf3e63dd24039e4b6f6fb89af6147 (MD5)
Approved for entry into archive by Sabrina Andrade (sabrinabeatriz@ibest.com.br) on 2013-10-17T17:51:18Z (GMT) No. of bitstreams: 1 Luciano.pdf: 10791164 bytes, checksum: abbbf3e63dd24039e4b6f6fb89af6147 (MD5)
Made available in DSpace on 2013-10-17T17:51:18Z (GMT). No. of bitstreams: 1 Luciano.pdf: 10791164 bytes, checksum: abbbf3e63dd24039e4b6f6fb89af6147 (MD5) Previous issue date: 2012
Os peixes da família Macrouridae apresentaram uma das maiores biomassas entre os peixes demersais em cruzeiros de pesquisa no Sudeste-Sul do Brasil entre 300-600m. Embora não sejam alvo da pesca no Brasil, estão entre os principais itens no descarte da pesca de arrasto no talude, sofrendo impacto similar às espécies-alvo. Dados de dois cruzeiros sazonais de arrasto de fundo foram utilizados para analisar a distribuição, abundância, densidade, composição de comprimentos e estimativas de biomassas para sete espécies de Macrouridae do talude superior do Sudeste-Sul do Brasil: Coelorinchus marinii, Malacocephalus occidentalis, M. laevis, Lucigadus ori, Hymenocephalus billsam, Ventrifossa macropogon e V. mucocephalus. A biomassa total foi estimada em 5,5 e 8,3 kt, respectivamente, no inverno-primavera e verão-outono, das quais C. marinii e M. occidentalis compuseram 98%. Amostras mensais da pesca comercial foram adicionalmente usadas para analisar a ecologia trófica das quatro espécies mais abundantes no talude superior do Sul do Brasil. Foram analisadas a composição da dieta, as mudanças ontogenéticas, as variações sazonais, a sobreposição alimentar intra e interespecífica, a fauna parasitária e aspectos da morfologia funcional relacionada à alimentação. C.marinii consumiu presas pequenas da infauna, epifauna, plâncton, nécton e carcaças, aproveitando presas em manchas ou agregações. M.occidentalis apresentou certa seleção por presas maiores e de coluna d’água, além de caranguejos e carcaças. As duas espécies apresentaram mudanças ontogenéticas e variações sazonais na composição da dieta, ocasionando mudanças nos padrões de sobreposição, mas em geral houve uma baixa sobreposição alimentar. As distintas morfologias funcionais encontradas refletiram em diferenças na dieta e nas estratégias de alimentação das espécies. Para C.marinii e M.occidentalis foram contruídos mapas com densidades, áreas de desova, índice alimentar, proporções de sexos e de imaturos/maturos, que foram relacionadas aos processos oceanográficos, fornecendo uma visão sobre as estratégias de vida e processos que regulam os padrões de distribuição e abundância. Ambas as espécies apresentaram variação sazonal na extensão e localização das áreas de desova. A maioria das fêmeas de C.marinii estavam maturas (90%), sugerindo que assentam ao fundo simultaneamente à maturação e que os juvenis são pelágicos, enquanto M.occidentalis apresentou muitos juvenis e poucas fêmeas maturas, assentando ao fundo bem antes da maturação. São identificados e descritos três processos responsáveis pelos padrões de distribuição e abundância encontrados nestas espécies. Sugere-se que áreas encontradas com elevadas biomassas de Macrouridae (carniceiros) sejam causadas por zonas de ocorrência semipermanente de processos de mesoescala (e.g. vórtices). Esses processos aumentam a produtividade e possibilitam elevadas biomassas de organismos de vida-curta encontradas em camadas superiores, e por outro lado, aumentam a concentração, mortalidade e disponibilidade de carcaças desses organismos, favorecendo predadores carniceiros. Esses processos podem ser responsáveis por inconsistências nas biomassas de magafauna e macrofauna encontradas em alguns estudos, onde biomassas de megafauna foram da mesma ordem de grandeza ou maiores que as de macrofauna, contradizendo o princípio Eltoniano.
Macrourids are among the most abundant and diverse demersal fishes in all deep oceans, including the Southwestern Brazilian continental slope. Although not targeted by Brazilian fisheries, they suffer impact similar than the target species, being among the most discarded fishes by deep bottom trawling. Trophic Ecology: Data from research surveys and commercial fishing were used to analyze the trophic ecology of four species inhabiting the upper slope of southern Brazil: Coelorinchus marinii, Malacocephalus occidentalis, M. laevis and Lucigadus ori. For the two abundant ones, ontogenetic changes, seasonal variations, intra- and interspecific dietary overlap, parasite fauna and aspects of functional morphology are also described. C.marinii had an extremely diverse diet, preying infauna, epifauna, plankton, necton and carcasses. M.occidentalis fed on larger and nektonic prey, but also included crabs and carcasses in the diet. Both species showed ontogenetic shifts and seasonal variations in diet composition, both leading to changes in intra- and interspecific diet overlap patterns. Species showed quite distinct feeding anatomy and proportions of body with mouth size, reflecting on feeding strategies. There was little interspecific food overlap. In most cases when the diet was more similar there was a spatial segregation. The coexistence of these species appears to be facilitated by the development of different functional morphologies and feeding strategies. A considerable portion of the diet of these species is due to the consumption of carcasses of pelagic and mesopelagic organisms, and even insects, bypassing the benthic trophic web. Conservative (minimum) estimates of the mean weight of carcasses in diet ranged from 3 to 20%, increasing with the size of the predators and towards deeper waters. C.marinii showed a lower consumption of carcasses and a high proportion of mesopelagic fishes and cephalopods, however, the analysis of the feeding morphology and prey size leads to believe that most of these two groups of prey were consumed as carcasses. This source of food bypass the detritus food chains and connect the concentrations of macrourids to fluctuations in the abundance of epi and mesopelagic organisms and to oceanographic processes that increase their concentration and mortality (e.g. mesoscale anticyclonic eddies). Distribution, Biomass and Oceanography: Data from two seasonal bottom trawl surveys were used to provide information on distribution, abundances, densities, sizecomposition and biomass estimates for seven species: Coelorinchus marinii, Malacocephalus occidentalis, M. laevis, Lucigadus ori, Hymenocephalus billsam, Ventrifossa macropogon and V. mucocephalus. The total biomass was estimated in 5.5 and 8.3 kt respectively in winter-spring and summer-autumn. C.marinii and M.occidentalis comprised 98% of the biomass. For these two abundant species, surface maps were made with spawning areas, feeding index, sex and immature/mature ratios, and were related to oceanographic processes, providing insights on strategies and important processes regulating distribution and abundance patterns. Both species showed a marked seasonal variation in the extent and location of spawning areas. Most C.marinii females were mature (90%), suggesting an early maturation during pelagic phase and acquiring demersal habit just prior the onset of maturation, while M.occidentalis showed few matures females and settle to bottom well before maturity. Temperature rather than depth seems to be the main factor regulating the batimetric distribution of both species. We describe three processes responsible for distribution and abundance patterns found in these species. Differentpatterns of spatial segregation were found in both species, related with depth, sex and maturity. It is suggested that areas with high biomass Macrouridae (scavengers) are induced by zones of occurrence semi-permanent mesoscale processes (e.g. eddies). These processes increase productivity and enable large biomass of short-lived organisms found in the upper layers, and also increase the concentration, mortality and availability of carcasses, favoring scavenger predators. These processes may be responsible for inconsistencies in biomass of megafauna and macrofauna found in some studies, where biomass of megafauna was of the same order of magnitude or larger than macrofauna, contradicting the Eltonian principle. It is suggested that future studies attempt to relate mesoscale processes with the biomass of potential short-lived prey in surface waters and higher biomass of scavengers. This work highlights the importance of the study of ocean dynamics, combining biological and oceanographic observations, trying to understand the role of mesoscale physical processes on the distribution and abundance patterns of species.

Styles APA, Harvard, Vancouver, ISO, etc.

44

Sosinski, Lilian Terezinha Winckler. « Introdução da truta arco-íris (Oncorhynchus mykiss) e suas conseqüências para a comunidade aquática dos rios de altitude do sul do Brasil ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/5173.

Texte intégral

Résumé :

A introdução de espécies exóticas é uma prática que acompanha a história da humanidade, sendo as espécies introduzidas a base da nutrição e economia em vários países. Porém, esse processo contínuo tem levado a uma homogeneização da flora e fauna global. Os ecossistemas aquáticos, que têm recebido menor atenção que os terrestres, têm sofrido perda de diversidade, hibridação, introdução de patógenos, degradação do habitat além da necessidade e alto custo de controle das espécies introduzidas. O desenvolvimento da aqüicultura tem acelerado a introdução de peixes exóticos, que são a base dessa produção em países como o Brasil. Além desta, entre as razões para a introdução citam-se o esporte, a manipulação ecológica com controle de organismos indesejáveis, o melhoramento dos estoques, a ornamentação ou ainda introduções acidentais. No Rio Grande do Sul, nos rios dos Campos de Cima da Serra estão ocorrendo introduções da espécie exótica truta arco- íris (Oncorhynchus mykiss) desde meados da década de 90 como forma de estímulo ao turismo rural. O objetivo dessa prática é a pesca esportiva, que atrai turistas de várias regiões. Porém, os rios da região possuem várias espécies de peixes endêmicas e as conseqüências dessa prática sobre a biota aquática são desconhecidas. O objetivo do presente trabalho é avaliar o efeito da introdução da truta arco-íris sobre o ecossistema de rios de baixa ordem no município de São José dos Ausentes – RS, Brasil. Para tanto foi descrita a biologia da truta arco- íris no novo ambiente, verificando sua alimentação, movimentação, presença e viabilidade da reprodução. A ictiofauna autóctone dos rios com ausência e presença de trutas foi comparada, bem como o efeito da predação sobre a macrofauna bentônica. A ictiofauna foi amostrada com o uso da pesca elétrica, sendo o conteúdo estomacal das trutas avaliado sazonalmente. Três trutas foram marcadas e acompanhadas por ii biotelemetria para determinação da sua área de vida. Um experimento com ninhos artificiais foi conduzido para verificação da sobrevivência de ovos de trutas nas condições dos rios de São José dos Ausentes. O experimento de exclusão de peixes foi feito a fim de avaliar o efeito da predação sobre a macrofauna bentônica, comparando a macrofauna em rios com e sem trutas. Os resultados indicaram que a truta arco- íris tem como alimento principal os invertebrados bentônicos, porém as maiores classes de tamanho incluem peixes em seus alimentos principais. Logo após sua introdução a movimentação é restrita, porém alguns exemplares foram capturados em um rio onde não foi feita introdução dessa espécie. Apesar de baixa, a sobrevivência dos adultos ocorre, assim como a reprodução. A sobrevivência dos ovos também é baixa, porém, uma pós-larva foi encontrada. A ictiofauna autóctone é diferenciada nos rios com presença de truta, apresentando menor riqueza e diversidade e uma tendência a diminuição da biomassa. A macrofauna bentônica também é diferenciada, apesar de não ser possível atribuir essa diferença somente à presença das trutas.
The introduction of exotic species is a practice that accompanies the humanity's history, being the introduced species the base of the nutrition and economy in several countries. Even so, that continuous process has been taking to a homogenization of the global flora and fauna. The aquatic ecosystems, that have been receiving smaller attention than the terrestrial ones, have been suffering diversity loss, hybridization, pathogens introduction, degradation of the habitat and costs of control of the introduced species. The development of aquaculture has been accelerating the introduction of exotic fish, that are the base of that production in countries as Brazil. Among the reasons for the introduction are the sporting fishing, the ecological manipulation with control of undesirable organisms, the improvement of the stocks, the ornamentation or still accidental introductions. In Rio Grande do Sul, in the rivers of Campos de Cima da Serra are occurring introductions of the species exotic rainbow trout (Oncorhynchus mykiss) from middles of the decade of 90 as incentive form to the rural tourism. The objective of that practice is the sporting fishing, which attracts tourists of several areas. Even so, the rivers of the area possess several endemic species of fish and the consequences of that practice on the aquatic biota have been ignored. The objective of the present work is to evaluate the effect of the introduction of the rainbow trout on rivers of low order in the municipal district of São José dos Ausentes - RS, Brazil. Thus the biology of the rainbow trout was described in the new environment, verifying its feeding, movement, presence and viability of reproduction. The autochthonous ictiofauna of the rivers with absence and presence of trouts was compared, as well as the effect of the predation on the benthic macrofauna. The ictiofauna was collected with the use of the electric fishing, being the stomacal content of the trouts evaluated seasonally. Three trouts were marked and accompanied by biotelemetry for determination of its life iv area. An experiment with artificial nests was driven for verification of the survival of eggs of trouts in the conditions of the rivers of São José dos Ausentes. The experiment of exclusion of fish was made in order to evaluate the effect of the predation on the benthic macrofauna, comparing the macrofauna in rivers with and without trouts. The results indicated that the rainbow trout has as main food benthic invertebrates, even so, in larger size classes it include fishes as main food. After its introduction the movement is restricted, even so trout s were found in a river where they were not introduced. Although low, have survival, as well as reproduction. The survival of the eggs is low, but it is happening in Silveira River, a post larvae being found. The autochthonous ictiofauna is differentiated in the rivers with trout presence, presenting smaller richness and diversity. The benthic macrofauna is also differentiated, in spite of not being possible to attribute that difference only to the presence of trouts.

Styles APA, Harvard, Vancouver, ISO, etc.

45

Santos, Niedja da Silva. « Chronic effects of carbamazepine on Danio rerio : a multi-parametric evaluation ». Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/18631.

Texte intégral

Résumé :

Mestrado em Toxicologia e Ecotoxicologia
Os fármacos são atualmente considerados contaminantes ambientais emergentes, devido à sua constante deteção nos ecossistemas aquáticos, consequência do aumento na sua produção, diversificação e consumo. A carbamazepina (Cbz) é um fármaco humano utilizado para tratamento de epilepsia, distúrbios bipolares e neuralgia trigeminal estando entre os fármacos mais prescritos no mundo e sendo considerado um marcador de poluição antropogénica. Para uma correta avaliação de risco ambiental é essencial avaliar os efeitos a longo termo dos compostos em vários níveis de organização biológica. Assim, os objetivos deste trabalho foram: i) avaliar a toxicidade crónica da Cbz para o peixe-zebra (Danio rerio) adulto, numa gama de concentrações que inclui uma concentração ambientalmente relevante (10 μg.L−1) e uma concentração correspondente a 5% do valor de concentração letal mediana (CL50) (10000 μg.L−1). Foram estudados efeitos no crescimento, comportamento alimentar, reprodução (número total de ovos e viabilidade), defesas antioxidantes (atividade da catalase - CAT e Glutationa S- transferase - GST), neurotransmissão (atividade da acetilcolinesterase - AChE), atividade metabólica (atividade da lactato desidrogenase - LDH) e anomalias nucleares eritrocíticas nos adultos expostos a Cbz; ii) avaliar a toxicidade aguda do propranolol (Prop) (um fármaco cardiovascular utilizado no controlo da hipertensão, angina pectoris e arritmia após enfarte agudo do miocárdio) para adulto D. rerio após previa exposição a Cbz, iii) avaliar alterações na suscetibilidade de embriões decorrente da exposição aguda ao Prop após exposição parental a Cbz. A exposição crónica do peixe-zebra a Cbz induziu alterações no tempo total de ingestão de alimento nas duas concentrações testadas e induziu inibição da CAT no fígado e brânquias (10 e 10000 μg.L−1). A GST apresentou uma resposta dependente do órgão, com um aumento de atividade nas brânquias (10 e 10000 μg.L−1) e fígado (10000 μg.L−1) e diminuição no intestino (10000 μg.L−1). A atividade da AChE aumentou na cabeça (10 e 10000 μg.L−1) e músculo (10000 μg.L−1), enquanto a atividade da LDH apresentou-se aumentada no fígado (10000 μg.L−1) e diminuída no músculo e brânquias na concentração de Cbz mais elevada (10000 μg.L−1). Em termos reprodutivos, a Cbz (10 e 10000 μg.L−1) diminuiu o número de ovos viáveis produzidos por peixe-zebra. A prévia exposição de adulto D. rerio a baixas concentrações de Cbz (0 e 10 μg.L−1) induziu 100% de mortalidade quando os organismos foram expostos ao Prop (1000 e 5000 μg.L−1) enquanto, organismos expostos a maior concentração de Cbz (10000 μg.L−1) apresentaram capacidade para tolerar o Prop. A exposição crónica a Cbz não teve no entanto efeitos significativos na taxa de crescimento dos organismos, não tendo igualmente sido detectadas anomalias nucleares eritrocíticas, indicadores de cito e genotoxicidade. Os descendentes não demonstraram alterações na susceptibilidade ao Prop, quando comparados com os organismos controlo. De uma forma geral, os dados obtidos neste trabalho sugerem que a exposição crónica a baixas concentrações de Cbz afeta o comportamento e processos bioquímicos no peixe-zebra com possíveis consequências a nível da reprodução.
Pharmaceuticals are emerging environmental contaminants due to their constant detection into aquatic ecosystems, as a response to the increase in the rate of production, high diversity, and high consumption. Carbamazepine (Cbz) is used to epilepsy treatment, bipolar disorders, trigeminal neuralgia, being among the most prescribed drugs in the world and is considered a marker of anthropogenic pollution. For a correct environmental risk assessment, it is essential to evaluate the long-term effects of the compounds in various levels of biological organization. The objectives of this study were: i) evaluate the chronic toxicity (63 days) of Cbz for adult Danio rerio at an environmentally relevant concentration (10 μg.L-1) and at a concentration close to 5% of the median lethal concentration (LC50) value (10000 μg.L-1). Effects were studied on growth, feeding behavior, reproduction (total number of eggs and viability), antioxidant defences (Catalase - CAT and Glutathione-S-Transferase - GST), neurotransmission (acetylcholinesterase activity – AChE), metabolic activity (lactate dehydrogenase - LDH) and nuclear abnormalities in adults exposed to Cbz; ii) to evaluate the acute toxicity of propranolol (Prop) (a cardiovascular pharmaceutical used to hypertension control, angina pectoris and arrhythmia after acute myocardial infarction) for adult D. rerio after chronic exposure to Cbz, iii) to evaluate changes in offspring susceptibility to acute exposure to Prop after parental exposure to Cbz and, in offspring. Chronic exposure of zebrafish to Cbz induced changes in total time for food intake at the two concentrations tested. Cbz exposure induced changes in enzymatic activity: CAT was inhibited in the liver and gills (10 and 10000 μg.L-1); GST presented an organ-dependent response with increased activity in the gills (10 and 10000 μg.L-1) and in the liver (10000 μg.L-1) and a decrease in enzyme activity in the intestine (10000 μg.L-1); the activity of AChE was increased in head (10 and 10000 μg.L-1) and muscle (10000 μg.L-1); while LDH showed increased activity in the liver and decreased in muscle and gills, these effects were observed in the highest concentration of Cbz (10000 μg.L-1). The number of eggs produced did not suffer changes; however, the number of viable eggs produced by zebrafish, exposed to Cbz was reduced (10 and 10000 μg.L-1). The previous exposure of adult D. rerio to low concentrations of Cbz (0 and 10 μg.L-1) induced mortality of 100% when these organisms were exposed to Prop (1000 and 5000 μg.L-1) while organisms exposed to a higher concentration of Cbz (10000 μg.L-1) were able to tolerate the Prop.The chronic exposure to Cbz did not induced significant effects in growth rate of the organisms and no erythrocytic nuclear abnormalities, cito and genotoxicity indicators were detected. The offspring did not show changes in Prop susceptibility, when compared with the control organisms. Overall, the data obtained in this work suggest that chronic exposure to low concentration of Cbz affects feeding behaviour and biochemical processes in zebrafish with possible consequences at reproduction level.

Styles APA, Harvard, Vancouver, ISO, etc.

46

Otani, Yosuke. « Feeding and reproductive strategies of ranging behavior in male Japanese macaques ». 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/189655.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

47

Emmerson, Derek Alan. « The effect of protein and energy self-selection on the reproductive performance of turkey hens ». Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53166.

Texte intégral

Résumé :

Two experiments were conducted to determine the effect of dietary self-selection of protein and energy on the reproductive performance of Large White turkey hens. The first study examined the effect of self-selection on reproductive performance during a production cycle that started in July and ended in December. Hens were maintained on one of two dietary regimes for a 20-week production cycle. Control birds were fed a conventional diet (18% crude protein, 2700 kcal/kg) which contained nutrients at levels recommended by the National Research Council (NRC, 1984). The remaining hens were allowed to select their diet from two feed sources: one relatively high in protein and low in energy (35% crude protein, 1850 kcal/kg) and the other relatively low in protein and high in energy (8% crude protein, 3220 kcal/kg). Hens fed the split diet produced an equal number of eggs as control hens but consumed significantly less feed (p≤.05). The diet that was selected contained approximately 40% less protein than the control diet (p≤.001) which resulted in significantly increased efficiency of protein utilization (eggs/kg protein) for hens fed the split-diet (p≤.001). In addition, the incidence of broodiness was significantly reduced in the split-diet treatment (p≤.10). Egg weight, fertility, hatchability and hatch of fertile eggs were not significantly effected by the dietary regimes. There was significantly greater body weight loss in hens fed the split-diet (p≤.05). Increasing trends in feed, energy, and protein consumptions were noted over the course of production. For this reason a second experiment was conducted to determine if these trends were the result of seasonal affects, due to changing ambient temperatures, or the result of changes in nutrient requirements of the turkey hen occurring with different stages of production. The second experiment was similar to Experiment 1 except that the production period started in March and ended in July. As in the first experiment, egg production was equal for hens in the two treatment groups. Feed intake and energy intake were not significantly different for hens fed the split and complete diets. However, as in the previous experiment, protein intake was significantly reduced in the split-diet treatment (p≤.001). The incidence of broodiness was again attenuated among split-fed birds (p≤.10). Average daily feed and energy intake appeared to decrease over the course of production which was presumed to be related to increasing ambient temperatures. As in the previous experiment, protein intake increased over the course of production despite increasing environmental temperatures. Therefore, the increased protein selection noted in these two experiments does not seem to be related to hot weather and may indicate an increased protein requirement in the later stages of egg production. Based on the finding that the incidence of broodiness was reduced among hens fed the split-diet, blood sera from hens in both experiments were analyzed for luteinizing hormone (LH) and prolactin (PRL). Although the incidence of broodiness was significantly reduced among birds fed the split-diet, there was no significant difference in serum LH and PRL concentrations. Therefore, the reduction in the incidence of broodiness that was noted in these experiments was not correlated with changes in the blood concentration of these hormones.
Master of Science

Styles APA, Harvard, Vancouver, ISO, etc.

48

Souza, Ursulla Pereira. « Biologia e ciclo de vida de Astyanax cf. scabripinnis paranae Eigenmann, 1914 (Characidae, Tetragonopterinae), no Ribeirão Grande, Parque Estadual da Serra do Mar, núcleo Santa Virginia, SP / ». Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/106542.

Texte intégral

Résumé :

Orientador: Francisco Manoel de Souza Braga
Banca: Leandro Müller Gomiero
Banca: Lilian Casatti
Banca: Mauricio Cetra
Banca: Lucia Ap. de Fatima Mateus
Resumo: O objetivo geral do presente estudo foi analisar a biologia e o ciclo de vida de Astyanax cf. scabripinnis paranae no ribeirão Grande, um riacho de cabeceira localizado no Parque Estadual da Serra do Mar (PESM), Núcleo Santa Virgínia, SP. Os exemplares foram coletados mensalmente de janeiro a dezembro em 2004 e 2006, utilizando-se redes de espera, redinha de mão e covo. Foram coletados dados de temperatura da água, oxigênio dissolvido e pH. Dados de pluviosidade, umidade relativa e temperatura do ar foram obtidos junto à Estação Meteorológica do PESM. Os peixes foram fixados em formalina a 10% e conservados em álcool 70%. No laboratório foram mensurados quanto ao comprimento total e padrão, peso e registrados os graus de repleção estomacal, de gordura acumulada, o sexo e os estádios de maturação gonadal. As correlações entre as variáveis ambientais e os meses de coletas foram verificadas por uma análise de componentes principais, que indicou uma separação entre períodos mais chuvosos (outubro a abril) e menos chuvosos (maio a setembro). A dieta foi analisada pelo grau de preferência alimentar. Diferenças no consumo de itens autóctones e alóctones e possíveis mudanças ontogenéticas ao longo do desenvolvimento da espécie foram verificadas por uma análise de correspondência. Para o estudo da reprodução foram analisadas as variações nos estádios de maturação, relação gonadossomática, grau de gordura acumulada, condição corporal, fecundidade e tipo de desova. O comprimento médio de primeira maturação gonadal foi estimado pelo ajuste não-linear e a condição corporal foi avaliada por modelos de análise de covariância. A fecundidade foi estimada pelo método volumétrico e relacionada ao comprimento padrão, ao peso total, ao peso das gônadas e à relação gonadossomática. No estudo do crescimento, a separação das coortes... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The present study aimed to analyze the biology and ecology of Astyanax cf. scabripinnis paranae in the Ribeirão Grande, a headwater stream located in the Parque Estadual da Serra do Mar (PESM), Núcleo Santa Virgínia, SP. The fishes were sampled monthly from January to December in 2004 and 2006, using gillnets, sieves and funnel traps. Temperature, dissolved oxygen and pH of the water were measured. Pluviometric data, relative humidity and temperature of the air were obtained in the Meteorological Station of PESM. The fishes were fixed in 10% formalin and conserved in 70% alcohol. In the laboratory they were measured as for the total and standard length, weighed and registered the degrees of stomach repletion, of accumulated fat, the sex and the stadiums of gonad maturation. The correlation structure among the environmental variables measured in the sampling collections was verified by a principal components analysis (PCA), which indicated a separation among rainier (October to April) and the less rainy periods (May to September). Differences in the consumption of autochthonous and allochthonous items and possible ontogenetic changes along the specimens development were verified by a correspondence analysis (CA). For the study of the reproduction the variations were analyzed at the maturation stadiums, gonadossomatic relationship, degrees of accumulated fat, corporal condition, fecundity and spawning type. The mean length of first gonad maturation was assessed by a no-linear adjustment. The corporal condition was evaluated by analysis of covariance. The fecundity was estimate by the volumetric method and related to the standard length, to the total weight, to the gonad weight and to the gonadossomatic relationship. In the study of the fish growth, the cohorts' separation and their mean lengths were obtained using the package "MIXDIST" and the Bhattacharya method... (Complete abstract click electronic access below)
Doutor

Styles APA, Harvard, Vancouver, ISO, etc.

49

Ornelas, Mário André Santos de. « Electronic sow feeding : making sense of feeding data to support sow management ». Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2021. http://hdl.handle.net/10400.5/21184.

Texte intégral

Résumé :

Dissertação de Mestrado Integrado em Medicina Veterinária
This study aimed to address the knowledge gaps concerning how group-housed gestating sows interact with modern electronic sow feeding (ESF) stations and to explore the potential of data recorded by these systems to enhance farm management. ESF records of 276 sow-gestations, from a dynamic group of c. 120 individuals were investigated. Data was analysed to identify patterns in the use of feeding stations by animals, and associations between feeding patterns and reproductive performance. Throughout the approximate 15 weeks that each sow spent on the dry sow house during a gestation, the total number of visits to the feeding stations varied greatly among individuals (367.7 ± 282.8) most of which were non-feeding visits (60.01 ± 19.8%). Feeding activity was highly concentrated within the first 12 h of feeding cycles (23 h) and sows ate their daily rations predominantly on a single feeding station visit (98.3 ± 1.7%). A mixed effects model revealed a weak effect of time on the number of feeding station visits, and a negative relationship between parity and total number of visits (b = - 0.230, SE = 0.022, p < 0.001). Sows kept feeding order relatively stable across gestation, especially among those who fed first. Additionally, results suggested that with every additional parity, the odds of a sow being among the first 15% group members to feed increased by a factor of 2.16 [OR: 2.16, p<0.010]. Statistically significant associations were found between feeding patterns and pre weaning piglet mortality, but not with number of piglets born alive nor average birth weight. Median piglet mortality was lower for sows feeding last compared to those feeding first (4.5% vs 14.3%, p = 0.025) and with a middle position in the feeding order (4.5% vs 11.8%, p = 0.045). Individuals with a regular feeding time showed higher piglet mortality rates than those with moderately regular (14.3% vs 10.6%, p = 0.029) and irregular (14.3% vs 9.5%, p = 0.047) feeding times. Median piglet mortality was superior in fast feeding sows compared to those feeding slower (13.3% vs 9.1%, p = 0.053). This work enhances current understanding of how gestating sows interact with ESF stations and highlights the potential of ESF data to support sow management.
RESUMO - ALIMENTAÇÃO ELETRÓNICA DE PORCAS: UTILIZAÇÃO DOS SEUS REGISTOS COMO SUPORTE AO MANEIO DA PORCA REPRODUTORA - Em suinicultura, o sucesso dos sistemas produtivos é influenciado em larga escala pelo desempenho do efetivo reprodutor. O maneio alimentar assume, a esse respeito, um papel decisivo na performance reprodutiva a médio e longo prazos e deve ter presentes as diferentes necessidades de cada animal. A alimentação eletrónica permite que porcas gestantes sejam alimentadas de forma individual estando alojadas em grupos, conforme previsto na legislação europeia. Ao passo que a adoção deste sistema tem vindo a crescer ao longo dos anos, a valorização dos seus registos tem recebido pouca atenção. Não obstante, alguns estudos sugerem que a informação recolhida automaticamente pelas estações de alimentação eletrónica (EAE) pode constituir uma ferramenta de monitorização, capaz de fomentar o maneio individual da porca gestante. Este trabalho visa enriquecer a compreensão do modo como as porcas em gestação em grupo interagem com EAE e avaliar a utilidade dos registos gerados por este sistema para apoiar o maneio da porca reprodutora. Para o efeito, analisaram-se registos de 276 gestações pertencentes a um grupo dinâmico de cerca de 120 porcas com acesso a duas EAE. A análise focou-se na identificação de padrões de utilização das EAE e no estudo de relações entre padrões de alimentação e performance reprodutiva. ...
N/A

Styles APA, Harvard, Vancouver, ISO, etc.

50

Teixeira, Rogerio Luiz. « Reproductive and feeding biology of selected syngnathids (Pisces : Teleostei) of the western Atlantic ». W&M ScholarWorks, 1995. https://scholarworks.wm.edu/etd/1539616873.

Texte intégral

Résumé :

The reproductive and feeding biology of five syngnathid species of the western Atlantic were studied: the pipefishes Syngnathus fuscus, S. floridae, the lined seahorse Hippocampus erectus of Chesapeake Bay; and the pipefishes S. folletti and Oostethus lineatus, from southern and southeast Brazil, respectively. Male syngnathids incubate eggs received from females in a ventral brood pouch, females do not play any additional role in parental care after mating. This natural sex role reversal is a unique characteristic that all male syngnathids have. In other fishes, parental care is usually a female prerogative. Most pipefishes are polygamous, while seahorses are monogamous. Syngnathus fuscus, S. floridae, and H. erectus have a protracted mating period from May through September in Chesapeake Bay, which varies with environmental conditions and eelgrass biomass. Female S. fuscus are dimorphic, gravid individuals undergo morphological and morphometric adaptations for mating. Female S. floridae and H. erectus are monomorphic. In both, S. fuscus and S. floridae, total sex ratio was skewed toward females, but the operational sex ratio was skewed toward males. Total and operational sex ratio in H. erectus were skewed toward females. In female S. fuscus (123 to 255 mm TL), fecundity was from 101 to 1,643 oocytes, whereas in males (83 to 189 mm TL) fertility was from 22 to 870 eggs/embryos. In female S. floridae (116 to 189 mm TL), fecundity was from 38 to 818 oocytes, whereas in males (91 to 176 mm TL) fertility was from 15 to 820 eggs/embryos. In female H. erectus (60 to 123 mm TL), fecundity varied from 90 to 1,313 oocytes, and in males (80 to 126 mm TL) fertility varied from 97 to 1,552 eggs/embryos. Mating period was not defined for S. folletti. Total sex ratio in this pipefish was skewed toward females, but the operational sex ratio was skewed toward males. Fecundity in females varied from 30 to 219 oocytes, and fertility measured for male brood pouches was from 26 to 181 eggs/embryos. Mating period was not defined for the estuarine and freshwater populations of the opossum pipefish, O. lineatus. Male opossum pipefish develop different coloration in the snout. In both populations, total sex ratio and operational sex ratio were not significantly different from the expected 1:1 ratio. In the estuarine population, fertility varied from 49 to 508 eggs/embryos (males from 101 to 165 mm TL), and in the freshwater population fertility varied from 280 to 897 eggs/embryos (males from 119 to 508 mm TL). Excepting O. lineatus, females in other pipefish species appear to limit males reproductive success. In the seahorse H. erectus, most females do not have the chance to find a mate inside Chesapeake Bay. In all syngnathids, snout size and width limit predation to small size prey. Syngnathus fuscus and H. erectus fed mainly on amphipods (Gammarus mucronatus, Ampithoe longimana, and Caprella penantis). Syngnathus floridae fed mainly on grass shrimps (Palaemonetes pugio and P. vulnaris). Southern pipefish fed predominantly on copepods. The estuarine population of O. lineatus fed more on stoneflies, whereas the freshwater population fed more on mayflies.&\sp*& ftn&\sp*&Originally published in DAI vol. 56. no. 3. Reprinted here with corrected text.

Styles APA, Harvard, Vancouver, ISO, etc.

Thèses sur le sujet « Feeding and reproduction »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres