Articles de revues : « Feeding and reproduction »

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Poole, Alan. « Courtship Feeding and Osprey Reproduction ». Auk 102, n^o 3 (1 juillet 1985) : 479–92. http://dx.doi.org/10.1093/auk/102.3.479.

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Abstract A female Osprey (Pandion haliaetus) usually is fed exclusively by its mate between pair formation and egg-laying. Laying dates and courtship periods-but not clutch size, egg size, breeding success, or female weight reserves-were correlated (negatively) with the prelaying feeding rates of 12 females breeding in a coastal Massachusetts colony. However, the age of a pair and of its bond influenced laying dates and courtship periods more than food intake. Older and more experienced pairs arrived earlier and laid eggs more quickly than younger pairs. As an independent test of food limitation in Ospreys producing eggs, supplemental food was provided to 4 nests during courtship. Supplemental food did not influence a female's reproductive output or timing, but males at nests receiving extra food showed reduced rates of foraging. Egg production boosted the daily energy expenditure of female Ospreys by only about 20% and females gained little weight during courtship, suggesting that egg-laying is not a demanding process in this species. Because age and mate retention had a greater effect on the reproductive output and timing of female Ospreys than rates of food consumption during courtship, and because there was evidence that poorly fed females were less willing to copulate and less faithful to their mates than well-fed females, it is argued that Osprey courtship feeding may function primarily to ensure mate fidelity.

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Santosa, Tomi Apra, Rani Dwi Suci Hd Putri, Ramadhan Sumarmin, Dwi Hilda Putri et Abdul Razak. « Meta-Analysis : Effectiveness of artificial feeding to increase growth rate and reproduction quality of Monopterus albus species ». Jurnal Biologi Udayana 25, n^o 1 (29 juin 2021) : 95. http://dx.doi.org/10.24843/jbiounud.2021.v25.i01.p11.

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The use of artificial feed for fish farming has been widely used at this time, however, it is not yet known the significant effect of artificial feed on the growth and reproduction rate of Monopterus albus. This study aims to determine the effectiveness of artificial feeding on the growth and reproduction rate of Monopterus albus species. This research is meta-analysis research. The data source comes from a search of 18 national and international articles published in 2010-2020 related to feeding the Monopterus albus species. Data obtained from google scholar database, DOAJ, ScienceDirect, sagejournal, Springer, and IEEE. The data analysis technique is a qualitative descriptive analysis with JASP software. The results showed that 35% of artificial feeding affected the growth of Monopterus albus and 28.5% affected the reproductive rate with an effect size of 1.2. This shows that artificial feeding has an effect of 0.334 in increasing the growth and reproductive quality of Monopterus albus.

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Holekamp, Kay E., et Scott Nunes. « Seasonal variation in body weight, fat, and behavior of California ground squirrels (Spermophilus beecheyi) ». Canadian Journal of Zoology 67, n^o 6 (1 juin 1989) : 1425–33. http://dx.doi.org/10.1139/z89-202.

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Annual cycles of activity and reproduction were documented in a population of California ground squirrels (Spermophilus beecheyi) in coastal California. Behavior, body mass, and reproduction were monitored in marked individuals between November 1983 and January 1986 through regular focal animal observation and livetrapping. Mass measures for reproductive tracts and gonadal fat pads were concurrently collected from a separate population of animals sacrificed in the laboratory. Mass and feeding behavior varied with sex and age. Surface activity, body weight, fat pad mass, and food consumption appeared to be closely related in this population. Fat pad mass was greater in nonreproductive than in reproductively active members of both sexes, as was body mass among males. Female body mass was greatest during pregnancy. Comparisons among reproductive status groups within each sex revealed significant differences in feeding, resting, vigilance, locomotor activity, and social behavior. Comparison with other populations suggested that S. beecheyi is highly variable with respect to demography, seasonal activity, timing of reproduction, and social behavior.

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Reuben, R. « Feeding and reproduction in vector mosquitoes ». Proceedings : Animal Sciences 96, n^o 3 (mai 1987) : 275–80. http://dx.doi.org/10.1007/bf03180010.

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Antacli, Julieta Carolina, Marina E. Sabatini, Ricardo I. Silva, Daniel R. Hernández, Andrés J. Jaureguizar et Rut Akselman. « FEEDING AND REPRODUCTIVE ACTIVITY OF THE COPEPODS Drepanopus forcipatus AND Calanus australis DURING LATE SUMMER ON THE SOUTHERN PATAGONIAN SHELF (ARGENTINA, 47°-55°S) ». Brazilian Journal of Oceanography 62, n^o 4 (décembre 2014) : 295–314. http://dx.doi.org/10.1590/s1679-87592014073406204.

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Drepanopus forcipatus and Calanus australis are key planktonic copepods on the southern Patagonian shelf. Their feeding and reproductive patterns and population status were investigated during late summer, when environmental conditions may be critical. The presence of food in the gut and food-pellet length were recorded in adult females and the most abundant copepodite stages. Diet composition was also studied in adult females. Female reproductive status was evaluated by gonad staging. Despite generally low feeding conditions and decreasing seasonal temperature, both copepods fed to some degree. The most numerous copepodites and adult females of both species showed similarly low feeding activity. About half of the adult females of the two species and C5s of C. australis contained food in their guts, but the proportion of fed C4-females of D. forcipatus was much lower. All copepods were generally feeding at low or intermediate levels. Gonad stage distribution and population structure showed low but still ongoing reproduction in both species. Gut content findings suggest a preference for smaller nanoplanktonic particles, especially dinoflagellates by D. forcipatus, and for autotrophic prey, particularly large diatoms by C. australis. The feeding and reproduction patterns of the two copepods were likely influenced by the distributions of potential food resources and temperature.

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Barrilli, Germano Henrique Costa, Julia Gomes do Vale, Gabriela Stahelin et Joaquim Olinto Branco. « Biological and ecological aspects of Bathygobius soporator (Valenciennes, 1837) (Perciformes, Gobiidae) from Santa Catarina, Southern Brazil ». Papéis Avulsos de Zoologia 61 (29 janvier 2021) : e20216115. http://dx.doi.org/10.11606/1807-0205/2021.61.15.

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Bathygobius soporator (popularly known as "Maria da toca") is a species that, although abundant, is little studied in aspects regarding growth, feeding and reproduction in southern Brazil. Studies on trophic ecology still raise questions on the species’ actual diet, especially in the context of algae participating as a food resource or an accidental intake. Thus, this study aims to fill this gap, evaluating the growth, feeding, and reproduction of this species. Monthly samples from two periods (1997-1998 and 2005-2006) were analyzed for growth, feeding, and reproduction parameters, totalizing 1177 individuals evaluated. Our results demonstrate that Bathygobius soporator is a species of fast development, reaching the age of first maturation before the first year of life. It presents a sexual dimorphism, being males larger than females. Reproductive peaks occur in the spring and summer months. The species presented a broad trophic spectrum, including algae as the main food resource, not just an accidental intake. The omnivorous-opportunistic trophic ecology of this species is emphasized, agreeing with the information of previous studies.

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Fuxman, Yakov L. « Reproduction rate, feeding process, and leibich limitations in cell populations—Part 1. Feeding stochasticity and reproduction rate ». Bulletin of Mathematical Biology 55, n^o 1 (janvier 1993) : 175–95. http://dx.doi.org/10.1007/bf02460301.

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FUXMAN, Y. « Reproduction rate, feeding process, and leibich limitations in cell populations—Part 1. Feeding stochasticity and reproduction rate ». Bulletin of Mathematical Biology 55, n^o 1 (janvier 1993) : 175–95. http://dx.doi.org/10.1016/s0092-8240(05)80068-0.

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Sutama, IK, TN Edey et IC Fletcher. « Studies on reproduction of Javanese thin-tail ewes ». Australian Journal of Agricultural Research 39, n^o 4 (1988) : 703. http://dx.doi.org/10.1071/ar9880703.

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Development of puberty (oestrus with ovulation) in two groups of 13 Javanese thin-tail (JTT) ewe lambs was studied from weaning at 13 weeks of age. The animals were fed ad lib. freshly chopped elephant grass plus either sufficient concentrate to grow at about 50 g per day (L) or ad lib. (H) concentrate from weaning to 5 weeks post-conception, and then studied through two pregnancies while on common feeding levels (Experiment 1). In Experiment 2, reproduction was studied in two groups of 13 JTT lambs which had been reared together and were given high or low nutrition from 5 weeks after their first conception until weaning of their second crop of lambs. The ewe lambs in Experiment 1 grew at 44 and 87 g per day (P < 0.01) for groups L and H respectively. Faster growth was associated with a younger age at first ovulation (190 v. 253 days), but differences in liveweight at first oestrus, first ovulation and puberty were marginal. Liveweight differences associated with differential feeding levels during rearing in Experiment 1 did not persist throughout the experimental period. Continuous high level feeding from early pregnancy (Experiment 2) resulted in a higher liveweight, and this was associated with higher ovulation rate (2.1 v. 1.6, P < 0.05) and an increase in the incidence of multiple births. However, this advantage in reproductive traits in the high feeding level group ewes was offset by higher wastage of ova (49 v. 20%) and higher pre-weaning lamb mortality (55 v. 33%). Average daily milk yield was non-significantly higher in the H group than in the L group in both lactations. In both experiments, improved feeding levels during rearing or thereafter reduced post-lambing re-breeding intervals. It was concluded that, while the JTT breed has unusually high, reproductive ability under low feeding regimes, most components of reproduction can be increased by strategic nutritional inputs.

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Hess, B. W., S. L. Lake, E. J. Scholljegerdes, T. R. Weston, V. Nayigihugu, J. D. C. Molle et G. E. Moss. « Nutritional controls of beef cow reproduction ». Journal of Animal Science 83, suppl_13 (1 juin 2005) : E90—E106. http://dx.doi.org/10.2527/2005.8313_supple90x.

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Abstract The livestock industry and animal scientists have long recognized the importance of proper nutrition for cattle to achieve reproductive success. Timely resumption of estrus following parturition is a major milestone that a cow must reach for optimal reproduction. Dynamic interplay among all strata of the hypothalamo-hypophyseal-ovarian axis occurs during the cow's transition from postpartum anestrus to reproductive competence. The reproductive axis integrates a milieu of nutritionally related signals that directly or indirectly affect reproduction. Directing nutritional inputs toward anabolic processes is critical to stimulating key events that promote reproductive success. Although prepartum and postpartum energy balance are the most important factors affecting duration of the postpartum interval to first estrus in beef cows, other nutritional inputs likely impinge on the hypothalamo-hypophyseal-ovarian axis to influence reproduction. For example, feeding fat to beef cows for approximately 60 d before calving may improve pregnancy rates in the upcoming breeding season. Supplementing postpartum diets with lipids high in linoleic acid can impede reproductive performance of beef cows. Precise mechanisms through which nutritional inputs mediate reproduction have not yet been fully elucidated. Scientists investigating nutritional mediators of reproduction, or how nutritional inputs affect reproduction, must be cognizant of the interactions among nutrients and nutritional cues responsible for mediating reproduction.

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Dorn, Nathan J., et Gary G. Mittelbach. « Effects of a native crayfish (Orconectes virilis) on the reproductive success and nesting behavior of sunfish (Lepomis spp.) ». Canadian Journal of Fisheries and Aquatic Sciences 61, n^o 11 (1 novembre 2004) : 2135–43. http://dx.doi.org/10.1139/f04-158.

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While crayfish are traditionally considered fish prey, they are capable of feeding on substrate-bound fish eggs and their introductions have been blamed for the decline in fish populations in Europe and North America. To investigate their potential effects on fish reproductive success we measured the effects of a native crayfish (Orconectes virilis) on the reproductive success of two substrate-nesting sunfish, pumpkinseed (Lepomis gibbosus) and bluegill (Lepomis macrochirus), in replicated pond experiments. Crayfish were observed feeding on eggs in both experiments. Crayfish presence delayed successful reproduction by pumpkinseeds in densely vegetated ponds, resulting in lower young-of-the-year biomass in ponds with crayfish. In the second experiment, with bluegills in less-vegetated ponds, crayfish prevented successful reproduction entirely. However, when we added crayfish-proof exclosures to the crayfish ponds late in the summer, bluegills located the crayfish-free habitat and successfully reproduced inside the exclosures (1 month after first successful reproduction in control ponds). The results of these experiments demonstrate the potential strong negative effects of crayfish on sunfish reproduction and suggest that the spatial distribution of crayfish and other egg predators may influence fish nesting behaviors and habitat choices. Further studies are needed to determine the magnitude of crayfish effects in natural lakes and ponds where sunfish and crayfish co-occur.

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Yanuartono, Yanuartono, Soedarmanto Indarjulianto, Alfarisa Nururrozi et Hary Purnamaningsih. « Peran Makromineral pada Reproduksi Ruminansia ». Jurnal Sain Veteriner 34, n^o 2 (1 décembre 2016) : 155. http://dx.doi.org/10.22146/jsv.27541.

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Macromineral is one component of a nutrient that has an important role in the growth, health, production,reproduction and immune system of animals. Ruminants need makromineral such as Ca, P, Mg, K, Na , Cl and S. Mineral needs of ruminant affected by several factors such as their age, pregnancy and lactation status.Mineral deficiency can cause disturbances in reproduction ruminant. Ca and P have direct influence while Mg, K, Na, Cl and S acted indirectly on reproductive function. A complete understanding of the role macromineral on ruminant reproductive function is indispensable for the prevention of their reproductive disorders due toimproper feeding minerals.

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SRIENC, F., A. G. FREDRICKSON et D. P. LAVIN. « Feeding, Growth, and Reproduction of Ciliate Microorganisms. » Annals of the New York Academy of Sciences 506, n^o 1 Biochemical E (novembre 1987) : 357–70. http://dx.doi.org/10.1111/j.1749-6632.1987.tb23833.x.

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Pan, Xiaoyue, Meredith J. Taylor, Emma Cohen, Nazeeh Hanna et Samantha Mota. « Circadian Clock, Time-Restricted Feeding and Reproduction ». International Journal of Molecular Sciences 21, n^o 3 (28 janvier 2020) : 831. http://dx.doi.org/10.3390/ijms21030831.

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The goal of this review was to seek a better understanding of the function and differential expression of circadian clock genes during the reproductive process. Through a discussion of how the circadian clock is involved in these steps, the identification of new clinical targets for sleep disorder-related diseases, such as reproductive failure, will be elucidated. Here, we focus on recent research findings regarding circadian clock regulation within the reproductive system, shedding new light on circadian rhythm-related problems in women. Discussions on the roles that circadian clock plays in these reproductive processes will help identify new clinical targets for such sleep disorder-related diseases.

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Ljungström, Gabriella, Tessa B. Francis, Marc Mangel et Christian Jørgensen. « Parent-offspring conflict over reproductive timing : ecological dynamics far away and at other times may explain spawning variability in Pacific herring ». ICES Journal of Marine Science 76, n^o 2 (10 août 2018) : 559–72. http://dx.doi.org/10.1093/icesjms/fsy106.

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Abstract Timing of reproduction may be of crucial importance for fitness, particularly in environments that vary seasonally in food availability or predation risk. However, for animals with spatially separated feeding and breeding habitats, optimal reproductive timing may differ between parents and their offspring, leading to parent-offspring conflict. We assume that offspring have highest survival and fitness if they are spawned around a fixed date, and use state-dependent life-history theory to explore whether variation in conditions affecting only parents (food availability and survival) may influence optimal timing of reproduction. We apply the model to Pacific herring (Clupea palasii) in Puget Sound, USA, where 20 subpopulations spawn at different times of the year. Our model suggests that relatively small differences in adult food availability can lead to altered prioritization in the trade-off between maternal fecundity and what from the offspring’s perspective is the best time to be spawned. Our model also shows that observed among-population variability in reproductive timing may result from adults using different feeding grounds with divergent food dynamics, or from individual variation in condition caused by stochasticity at a single feeding ground. Identifying drivers of reproductive timing may improve predictions of recruitment, population dynamics, and responses to environmental change.

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Abram, Paul K., Jacques Brodeur, Alberto Urbaneja et Alejandro Tena. « Nonreproductive Effects of Insect Parasitoids on Their Hosts ». Annual Review of Entomology 64, n^o 1 (7 janvier 2019) : 259–76. http://dx.doi.org/10.1146/annurev-ento-011118-111753.

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The main modes of action of insect parasitoids are considered to be killing their hosts with egg laying followed by offspring development (reproductive mortality), and adults feeding on hosts directly (host feeding). However, parasitoids can also negatively affect their hosts in ways that do not contribute to current or future parasitoid reproduction (nonreproductive effects). Outcomes of nonreproductive effects for hosts can include death, altered behavior, altered reproduction, and altered development. On the basis of these outcomes and the variety of associated mechanisms, we categorize nonreproductive effects into ( a) nonconsumptive effects, ( b) mutilation, ( c) pseudoparasitism, ( d) immune defense costs, and ( e) aborted parasitism. These effects are widespread and can cause greater impacts on host populations than successful parasitism or host feeding. Nonreproductive effects constitute a hidden dimension of host–parasitoid trophic networks, with theoretical implications for community ecology as well as applied importance for the evaluation of ecosystem services provided by parasitoid biological control agents.

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Dobson, F. Stephen, et Pierre Jouventin. « The trade-off of reproduction and survival in slow-breeding seabirds ». Canadian Journal of Zoology 88, n^o 9 (septembre 2010) : 889–99. http://dx.doi.org/10.1139/z10-054.

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A trade-off between reproduction and survival is one of the most consistent empirical aspects of life-history diversification. One explanation for this interspecific pattern is evolved differences in the balance of allocation to reproduction versus individual maintenance and survival. The same pattern is expected, however, simply as a result of differences among species in body size. We tested these alternatives using original data from 44 species of albatrosses and petrels, long-lived seabirds that breed very slowly. After application of regression techniques to remove the effects of body size and phylogeny, annual reproduction and survival exhibited a significant trade-off. Our measures of reproductive effort also exhibited significant trade-offs with age at maturity, the latter strongly associated with survival. Feeding rate of chicks, success at fledging chicks, and annual chick production were also significantly associated. In conclusion, after removing the effects of body size, we found a significant trade-off of reproduction and survival, in spite of the fact that these long-lived birds lay only one egg at a time. Our examination of the pattern among life-history traits of these slow breeders and their pelagic feeding ecology provide support for the evolutionary explanation of a trade-off of reproduction and survival.

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Khulal, Aarati, Prativa Sharma, Asmin Khulal et Surya Sharma Bhatta. « A REVIEW ARTICLE ON NON-GENETIC FACTORS AFFECTING REPRODUCTIVE TRAITS IN SWINE ». Malaysian Animal Husbandry Journal 1, n^o 2 (3 septembre 2021) : 71–76. http://dx.doi.org/10.26480/mahj.02.2021.71.76.

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This review studies several factors affecting the reproductive performance of swine chiefly focusing on sow-related factors, which have significant economic importance. A sow’s productivity is determined by different reproductive attributes, including litter size, litter weight at weaning, farrowing rate, the return of oestrus, and many more. The increase in number of pigs born alive and weaned piglets per sow is an aim for swine husbandry.Various factors such as parity, housing, feed, gestation length, season, and temperature are considered in this paper. Sows of differing parities have performed differently.The performance was influenced by various feeding systems, comfort, spacing, aggressiveness, and disease transmission in the housing system. Feeding intake and nutrition uptake are directly connected with milk secretion as well as other traits. Season and temperature are correlated with feeding intake, time of puberty, hormonal production, and seasonal infertility.Scientists are globally working for productive breeds. However, the rearing of swine will necessitate the consideration of different non-genetic factors of their reproduction from an economicpoint of view.The goal of this study is to understand non-genetic factors that affect sow reproduction and to advise swine farmers on how to create a better environment for swine to improve productivity.

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Gaston, A. J. « Energy Invested in Reproduction by Thick-Billed Murres (Uria lomvia) ». Auk 102, n^o 3 (1 juillet 1985) : 447–58. http://dx.doi.org/10.1093/auk/102.3.447.

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Abstract Pelagic seabirds that lay single-egg clutches have been thought to invest less energy in reproduction than inshore-feeding species that rear more than one young. To examine this idea I calculated time and energy budgets for Thick-billed Murres (Uria lomvia) breeding at two large arctic colonies and compared their energy expenditure with that of a hypothetical group (shirkers) that was capable of feeding at the same rate but did not attempt any reproductive activity. The difference in energy investment between breeders and shirkers was strongly dependent on the average foraging range. I also compared my results with similar estimates for inshore-feeding Black Guillemots (Cepphus grylle). For the two Thick-billed Murre colonies, energy allocated to reproduction represented 30% and 24% of total energy expenditure during the breeding season. These values exceed the estimates for Black Guillemots. The amount of energy invested by Thick-billed Murres at the colonies considered probably is similar to that invested by other seabirds laying larger clutches and rearing heavier young.

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Gao, Xu, Changnan Jin, Arley Camargo et Yiming Li. « Allocation trade-off under climate warming in experimental amphibian populations ». PeerJ 3 (20 octobre 2015) : e1326. http://dx.doi.org/10.7717/peerj.1326.

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Climate change could either directly or indirectly cause population declines via altered temperature, rainfall regimes, food availability or phenological responses. However few studies have focused on allocation trade-offs between growth and reproduction under marginal resources, such as food scarce that may be caused by climate warming. Such critical changes may have an unpredicted impact on amphibian life-history parameters and even population dynamics. Here, we report an allocation strategy of adult anuran individuals involving a reproductive stage under experimental warming. Using outdoor mesocosm experiments we simulated a warming scenario likely to occur at the end of this century. We examined the effects of temperature (ambient vs. pre-/post-hibernation warming) and food availability (normal vs. low) on reproduction and growth parameters of pond frogs (Pelophylax nigromaculatus). We found that temperature was the major factor influencing reproductive time of female pond frogs, which showed a significant advancing under post-hibernation warming treatment. While feeding rate was the major factor influencing reproductive status of females, clutch size, and variation of body size for females, showed significant positive correlations between feeding rate and reproductive status, clutch size, or variation of body size. Our results suggested that reproduction and body size of amphibians might be modulated by climate warming or food availability variation. We believe this study provides some new evidence on allocation strategies suggesting that amphibians could adjust their reproductive output to cope with climate warming.

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Farahi, Sara, Parviz Shishehbor et Alireza Nemati. « Bisexual and oedipal reproduction of Macrocheles muscaedomesticae (Acari, Macrochelidae) feeding on Musca domestica (Diptera, Muscidae) eggs ». Acarologia 58, n^o 2 (15 mars 2018) : 430–41. http://dx.doi.org/10.24349/acarologia/20184251.

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Macrocheles muscaedomesticae (Scopoli) is a predatory mesostigmatic mite that inhabits different manure microhabitats and preys mostly on housefly (Musca domestica L.) eggs. When a virgin female colonizes a new manure substrate, it produces male offspring through parthenogenesis (arrhenotoky); when her sons reach maturity, oedipal mating takes place and the female begins to produce bisexual offspring. In order to examine the consequence of oedipal reproduction on population development, we designed two separate experiments to compare life history traits and life table parameters of oedipal versus bisexual cohorts of M. muscaedomesticae, using the age-stage, two sex life table method. Experiments were conducted at 28 +/- 1 °C, using a photoperiod of 14:10 (L: D) h, and 65 +/- 5% relative humidity, with housefly eggs used to feed mites. Mean adult female longevity was 38.63 days, and fecundity 128.51 offspring under bisexual reproduction, and 37.48 days and 68.23 offspring under oedipal reproduction. In the bisexual cohort, the intrinsic rate of increase (rm), the finite rate of increase (λ), the net reproduction rate (R0), the gross reproductive rate (GRR) and the mean generation time (T) of M. muscaedomesticae were 0.2938 d-1, 1.3415 d-1, 54.216 offspring/individual, 77.7 offspring/individual and 13.5885 days, respectively. Because only male eggs were produced during the first 5.62 days (on average) of the oviposition period in the oedipal cohort, it was theoretically incorrect to compute the population parameters using the survival and fecundity values for this group, even though bisexual reproduction did occur after this period. Our findings determined that the effect of oedipal reproduction could be correctly defined and analyzed by using the age-stage, two-sex life table method. Our results demonstrated that virgin females are able to produce and copulate with their sons (oedipal mating), which then allows those females to produce both sexes. This reproductive system can enable this valuable natural enemy to considerably extend its distribution potential.

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Popara, Marina, Margarita Villar, Lourdes Mateos-Hernández, Isabel G. Fernández de Mera et José de la Fuente. « Proteomics Approach to the Study of Cattle Tick Adaptation to White Tailed Deer ». BioMed Research International 2013 (2013) : 1–8. http://dx.doi.org/10.1155/2013/319812.

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Cattle ticks,Rhipicephalus (Boophilus) microplus, are a serious threat to animal health and production. Some ticks feed on a single host species while others such asR. microplusinfest multiple hosts. White tailed deer (WTD) play a role in the maintenance and expansion of cattle tick populations. However, cattle ticks fed on WTD show lower weight and reproductive performance when compared to ticks fed on cattle, suggesting the existence of host factors that affect tick feeding and reproduction. To elucidate these factors, a proteomics approach was used to characterize tick and host proteins inR. microplusticks fed on cattle and WTD. The results showed thatR. microplusticks fed on cattle have overrepresented tick proteins involved in blood digestion and reproduction when compared to ticks fed on WTD, while host proteins were differentially represented in ticks fed on cattle or WTD. Although a direct connection cannot be made between differentially represented tick and host proteins, these results suggested that differentially represented host proteins together with other host factors could be associated with higherR. microplustick feeding and reproduction observed in ticks fed on cattle.

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Laflamme, L. F., et M. L. Connor. « Effect of postpartum nutrition and cow body condition at parturition on subsequent performance of beef cattle ». Canadian Journal of Animal Science 72, n^o 4 (1 décembre 1992) : 843–51. http://dx.doi.org/10.4141/cjas92-096.

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Seventy-two cows were used in each of 2 yr to study the effect of body condition (BC) and postpartum grain feeding on cow and calf weights and on reproductive traits. Cows reached a BC score of 4 or 6 by parturition and were fed 0 or 4 kg mixed grain d−1 during the postpartum period. All cows were fed grass silage throughout the trial. Grain feeding had no effect on weight gains but increased BC of the lactating cows. Presence of ovarian follicles, uterine involution and pregnancy rate were the only reproductive parameters generally affected by grain feeding. Body condition score had no effect on calf performance, but an increase in BC at parturition yielded an improvement of most of the reproductive traits measured. No interaction was observed between BC and postpartum grain feeding, suggesting that all cows responded similarly to the treatments. Under the conditions of this trial, it was shown that BC at parturition was an important factor affecting cow performance, but the reproductive intervals were directly related to the physiological state of the cow at the beginning of the breeding season. Key words: Cow, body condition, gain, postpartum grain feeding, reproduction

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Hoey, Andrew S., David R. Bellwood et Adam Barnett. « To feed or to breed : morphological constraints of mouthbrooding in coral reef cardinalfishes ». Proceedings of the Royal Society B : Biological Sciences 279, n^o 1737 (8 février 2012) : 2426–32. http://dx.doi.org/10.1098/rspb.2011.2679.

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Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes.

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Freitas, Priscilla Pimentel, Vanair Carlos da Paz et Rodrigo Diana Navarro. « Feeding behavior of cockatiels in captivity ». Brazilian Journal of Veterinary Research and Animal Science 57, n^o 4 (3 décembre 2020) : e168320. http://dx.doi.org/10.11606/issn.1678-4456.bjvras.2020.168320.

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In nature, cockatiel (Nymphicus hollandicus) feed consists of a huge variety of seeds, fruits, flowers, leaves, and insects. In captivity, their feed is generally poor, as many breeders offer only a mixture of seeds as food, leading to nutrient deficiency and even obesity. This paper presents a study on cockatiel feeding behavior in artificial environments at different stages of development (growth, maintenance, and reproduction), to evaluate their preference from the offer of six different food types (sunflower seed, oats, millet, rice, ration, and a cornmeal based feed or farinhada), and an analysis of their preferences for locations in the cage. No significant differences were observed about the final weight of the birds during the stages of development. Consumption of millet seeds was significantly higher in the growth stage, but at this stage, the birds showed a preference for oats. On the other hand, at the reproduction and maintenance stages, they showed a preference for sunflower seeds. The birds in the reproduction stage were the ones that visited the nest, and the nest grid, the most. Among all the cage locations, all birds showed a preference for the perches.

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Sahota, T. S., J. F. Manville, F. G. Peet, A. Ibaraki et E. White. « WEEVIL PHYSIOLOGY CONTROLS THE FEEDING RATES OF PISSODES STROBI ON PICEA SITCHENSIS ». Canadian Entomologist 130, n^o 3 (juin 1998) : 305–14. http://dx.doi.org/10.4039/ent130305-3.

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AbstractThe number and volume of feeding and oviposition holes made by female white pine weevils, Pissodes strobi (Peck), on lateral branches of resistant and susceptible Sitka spruce, Picea sitchensis (Bong.) Carr., were determined. When all possible effects of weevil reproduction on feeding rates were eliminated, by using reproductively noncompetent weevils, there was no significant difference in the number of feeding holes made on the two host types. In addition, the volume of feeding holes was unaffected by host type on day 1. In contrast, when differential reproductive activity was induced by treating weevils with juvenile hormone, and the host factor was eliminated, by using only the susceptible host, higher reproductive activity was accompanied by a significantly larger number of feeding holes. Hormone treatment also led to an increase in the volume of feeding holes in the absence of any influence of host factors. Results are interpreted in relation to the direct effects of host resistance on feeding rates (which determine host acceptability) and the indirect effects of host resistance on feeding rates mediated through the physiology of the weevils (which determine host suitability). Our results show that both the number of feeding holes and their volume are determined primarily through weevil metabolism.

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DOBRESCU, OLGA. « Photoperiod, Diet, and Method of Feeding on Reproduction ». Poultry Science 65, n^o 3 (mars 1986) : 559–64. http://dx.doi.org/10.3382/ps.0650559.

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Marques, Otavio A. V., et Giuseppe Puorto. « Feeding, reproduction and growth in the crowned snake ». Amphibia-Reptilia 19, n^o 3 (1998) : 311–18. http://dx.doi.org/10.1163/156853898x00214.

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AbstractThe crowned snake Tantilla melanocephala is a small fossorial sonorine snake, widely distributed through South America. Dissection of 186 specimens, combined with observations of captive specimens, provided information on the natural history of this species in southeastern Brazil. Females attained larger body sizes than males. Apparently T. melanocephala forage at night for active prey. Centipedes of the genus Otostigmus were the main prey item. These centipedes are subdued by injection of venom. Data from preserved specimens showed no significant seasonal variation in the number of collected snakes. Reproduction seemed to be highly seasonal with vitellogenesis occurring from onset to the middle of the rainy season and hatching at the end of the rainy season. Clutch size ranged from one to three and was correlated with female body length. Neonates measured 10-12 cm snout-vent length and juveniles attained about 17.5 cm SVL during the first year. Apparently males attain sexual maturity at an age of about 10 months and females at about 20 months.

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Harris, R. « Feeding, growth, and reproduction in the genus Calanus ». ICES Journal of Marine Science 57, n^o 6 (décembre 2000) : 1708–26. http://dx.doi.org/10.1006/jmsc.2000.0959.

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Hohmann, John G., Thomas H. Teal, Donald K. Clifton, James Davis, Victor J. Hruby, Guoxia Han et Robert A. Steiner. « Differential role of melanocortins in mediating leptin's central effects on feeding and reproduction ». American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 278, n^o 1 (1 janvier 2000) : R50—R59. http://dx.doi.org/10.1152/ajpregu.2000.278.1.r50.

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Leptin serves as a humoral link coupling the status of energy reserves to the functional activity of the reproductive system. Leptin is thought to act through melanocortinergic pathways in the brain to regulate ingestive behaviors; however, whether melanocortins mediate leptin's actions on the neuroendocrine-reproductive axis is unknown. We tested this hypothesis first by determining whether the effects of leptin on feeding behavior and reproduction in the ob/ob mouse could be blocked by the melanocortin receptor (MC-R) antagonist SHU9119 and second, by examining the effects of the MC-R agonist MTII on feeding and the endocrine-reproductive system. Administered by intracerebroventricular injections, leptin inhibited food intake, raised plasma gonadotropin levels, and increased seminal vesicle weights compared with controls; SHU9119 (intracerebroventricularly) attenuated leptin's effects on food intake and body weight but did not alter leptin's stimulatory effect on the reproductive axis. MTII (intracerebroventricularly and intraperitoneally) decreased food intake and increased body temperature compared with controls but had no effect on the reproductive-endocrine axis. These results suggest that although leptin acts centrally through melanocortinergic pathways to inhibit ingestive behaviors and stimulate metabolism, leptin's activational effect on the reproductive axis is likely to be mediated by other, unknown neuroendocrine circuits.

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Kouamé, K. L., et M. Mackauer. « INFLUENCE OF STARVATION ON DEVELOPMENT AND REPRODUCTION IN APTEROUS VIRGINOPARAE OF THE PEA APHID, ACYRTHOSIPHON PISUM (HARRIS) (HOMOPTERA : APHIDIDAE) ». Canadian Entomologist 124, n^o 1 (février 1992) : 87–95. http://dx.doi.org/10.4039/ent12487-1.

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AbstractThe influence of nutrient stress on growth, development, and reproduction in apterous virginoparae of the pea aphid, Acyrthosiphon pisum (Harris), was investigated in the laboratory. We tested the hypothesis that species with a high reproductive investment have low resistance to starvation. Aphids in two groups were starved daily from birth for 4 h and 6 h, respectively, and compared with feeding counterparts reared on leaves of broad beans, Vicia faba L. Aphid wet weight increased as an exponential function of age in all groups. Starved aphids had lower adult weight and required longer from birth to parturition than feeding aphids. These effects increased with the length of daily starvation. The number of offspring produced was correlated with adult dry weight. Aphids were unable to compensate, or to compensate completely, for water and nutrient loss resulting from starvation. It is suggested that pea aphids allocate resources first to maintenance and then to reproduction when deprived of food.

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Gao, Qian, et Tamas L. Horvath. « Cross-talk between estrogen and leptin signaling in the hypothalamus ». American Journal of Physiology-Endocrinology and Metabolism 294, n^o 5 (mai 2008) : E817—E826. http://dx.doi.org/10.1152/ajpendo.00733.2007.

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Obesity, characterized by enhanced food intake (hyperphagia) and reduced energy expenditure that results in the accumulation of body fat, is a major risk factor for various diseases, including diabetes, cardiovascular disease, and cancer. In the United States, more than half of adults are overweight, and this number continues to increase. The adipocyte-secreted hormone leptin and its downstream signaling mediators play crucial roles in the regulation of energy balance. Leptin decreases feeding while increasing energy expenditure and permitting energy-intensive neuroendocrine processes, such as reproduction. Thus, leptin also modulates the neuroendocrine reproductive axis. The gonadal steroid hormone estrogen plays a central role in the regulation of reproduction and also contributes to the regulation of energy balance. Estrogen deficiency promotes feeding and weight gain, and estrogen facilitates, and to some extent mimics, some actions of leptin. In this review, we examine the functions of estrogen and leptin in the brain, with a focus on mechanisms by which leptin and estrogen cooperate in the regulation of energy homeostasis.

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Giesecke, Ricardo, et Humberto E. González. « Reproduction and feeding of Sagitta enflata in the Humboldt Current system off Chile ». ICES Journal of Marine Science 65, n^o 3 (18 mars 2008) : 361–70. http://dx.doi.org/10.1093/icesjms/fsn030.

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Abstract Giesecke, R., and González, H. E. 2008. Reproduction and feeding of Sagitta enflata in the Humboldt Current system off Chile. – ICES Journal of Marine Science, 65: 361–370. This study is based on 3 years (August 2002–July 2005) of monthly zooplankton sampling at a fixed station located 18 km off Coliumo Bay (36°S), Chile. The reproduction of Sagitta enflata, its feeding rate, specific daily ration, and prey selectivity were analysed and related to several environmental variables: temperature, salinity, dissolved oxygen, chlorophyll a concentrations, and both meso- and micro-zooplankton abundance. The main predatory activity of S. enflata was centred on the copepods Paracalanus parvus, Oithona spp., and Calanus chilensis. These three species were consumed at different rates, depending mainly on the maturity of the S. enflata population. When Stages I and II individuals dominated, predation focused on the small P. parvus and Oithona spp., whereas more mature populations (Stages III and IV) preyed selectively on C. chilensis. The mean specific daily ration of 0.1 d−1 increased to 0.5 d−1 before and during maturation. The reproductive phase of S. enflata was closely coupled with the abundance of nauplii, suggesting that chaetognath reproduction paralleled that of copepods, most likely to diminish the mortality of its offspring resulting from starvation. The relationships between these were included in a conceptual model and their ecological significance is discussed.

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Keats, D. W., G. R. South et D. H. Steele. « Reproduction and egg guarding by Atlantic wolffish (Anarhichas lupus : Anarhichidae) and ocean pout (Macrozoarces americanus : Zoarcidae) in Newfoundland waters ». Canadian Journal of Zoology 63, n^o 11 (1 novembre 1985) : 2565–68. http://dx.doi.org/10.1139/z85-382.

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The reproductive season, the sex that provides parental care, and the relationship of feeding with reproduction are reported for Atlantic wolffish and ocean pout in eastern Newfoundland. Both species move into shallow water in the spring, pair during the summer, and spawn in holes under and between boulders during the autumn. Apparently, male Atlantic wolffish provide solitary parental care of the eggs, while in ocean pout females provide this function. Feeding is reduced for females and probably males of both species as the gonads approach maximum size. After pair formation, male ocean pout reduce feeding; male Atlantic wolffish do so to a lesser degree. Male Atlantic wolffish and female ocean pout feed little or not at all while guarding egg masses.

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Shepherd, Julian G. « Mating, Sperm Transfer and Oviposition in Soft Ticks (Acari : Argasidae), a Review ». Pathogens 12, n^o 4 (12 avril 2023) : 582. http://dx.doi.org/10.3390/pathogens12040582.

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This review addresses the physiology and behavioral events involved in the reproduction of soft ticks (family Argasidae), with special attention to the events of their adult life: mating, sperm transfer and egg-laying. Many of these aspects are held in common with hard ticks, but the repeated short duration of feeding bouts in soft ticks, in contrast to the extended single engorgements of hard ticks, has consequences peculiar to soft tick reproduction. Reviewed are the dramatic external mechanism of sperm transfer, the unusual maturation and unique morphology and motility of the spermatozoa, the mechanism of oogenesis and its hormonal control, the mystery of fertilization, the involvement of pheromones in mating, the control of reproductive arrests and the vertical transmission of symbiotes in reproduction. Jumping-off points for further investigation are discussed throughout.

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Johnson, A. K., R. Anne Richards, Daniel W. Cullen et Sandra J. Sutherland. « Growth, reproduction, and feeding of large monkfish, Lophius americanus ». ICES Journal of Marine Science 65, n^o 7 (8 septembre 2008) : 1306–15. http://dx.doi.org/10.1093/icesjms/fsn138.

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Abstract Johnson, A. K., Richards, R. A., Cullen, D. W., and Sutherland, S. J. 2008. Growth, reproduction, and feeding of large monkfish, Lophius americanus. – ICES Journal of Marine Science, 65: 1306–1315. The American monkfish, Lophius americanus, supports important commercial fisheries in the Northwest Atlantic. Although life history information is available for smaller L. americanus, the biology of large monkfish (>70 cm) is poorly understood because relatively few large fish are caught in standard resource surveys. Between 2006 and 2008, 699 L. americanus of 71–118 cm total length were collected from commercial gillnet fishers operating in the mid-Atlantic Bight (n = 689) and in the Gulf of Maine (n = 10) to investigate growth rates, reproductive biology, and feeding habits of large monkfish. All those collected were mature females ranging in age from 7 to 13 years. Growth was linear at an average annual rate of 7.6 cm. Hepatosomatic indices peaked in February and gonadosomatic indices between February and April. Postovulatory follicles and vitellogenic oocytes were observed in the same ovaries, evidence that monkfish spawn over a protracted period and possibly more than once annually. Food habits were similar to those reported for smaller benthic phase monkfish, but cannibalism was more prevalent in large fish (5.6% frequency of occurrence). Frequencies of feeding and cannibalism were greatest in females in the final stage of oocyte maturation.

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Skliarov, Pavlo, Serhiy Fedorenko, Svitlana Naumenko, Oleksandr Onyshchenko, Alina Pasternak, Liliya Roman, Maryna Lieshchova, Dmytro Bilyi et Olga Bobrytska. « Reviewing Effective Factors of Alimentary Deficiency in Animals Reproductive Functions ». World's Veterinary Journal 11, n^o 2 (25 juin 2021) : 157–69. http://dx.doi.org/10.54203/scil.2021.wvj21.

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Animal reproduction is one of the main factors limiting the efficiency of livestock production. Its optimal level is possibly achieved when certain conditions are created for animals. As reproduction is a complex reflex process depending on neuroendocrine regulatory mechanisms, the character and strength of stimuli, which, in turn, is due to a number of factors. Under normal conditions, the body of animals is affected by many different factors, which are appropriately transformed and specified by positive or negative reactions. Inhibitory factors include air pool, saturated with harmful substances and gases, ionizing radiation, poor water quality along with altered redox properties, hypokinesia combined with poor unbalanced feeding, systematic chronic stress, presence of toxic substances in feed, and the deficiency of vitamins and other bioantioxidants in feed or their excessive spending. Of the wide range of genetic and paratypic factors of negative impacts on reproductive capacity, the most common one is alimentary, which causes impaired reproductive function due to deficiencies in the rules, regulations, and feeding regime of animals. In particular, the alimentary can be associated with both general malnutrition (starvation) and overfeeding (obesity). However, the alimentary form of infertility mostly occurs due to low-quality diets when the diet lacks vital components (mainly vitamins, macro-, and micronutrients) or the quantitative ratios of the ingredients are violated. This is possible even if the total nutritional value of the diet meets the established requirements for the physiological needs of the body. Vitamins, micro-, and macronutrients are ecologically deficient factors of disturbance of animal reproductive function, the influence of which is observed on all processes of reproduction, from fertilization to the postpartum period and the preservation of young animals. The pathogenesis of their insufficiency is associated with the violation of steroido-, gameto-, and embryogenesis and the emergence of ante-, intra-, neo- and postnatal pathologies, respectively. Therefore, treatments and prevention measures should be aimed at providing animals with biologically complete balanced feeding and replenishment of the body with vitamins and minerals. However, all these issues remain incompletely studied and need further research.

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Magris, Martina, et Cristina Tuni. « Enough for all : no mating effort adjustment to varying mate availability in a gift-giving spider ». Behavioral Ecology 30, n^o 5 (19 juin 2019) : 1461–68. http://dx.doi.org/10.1093/beheco/arz102.

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Males of a gift-giving spider do not modify their allocation to reproduction when mating opportunities vary. Due to their costly courtship via provision of food gifts to females, with high female availability males should reduce their reproductive investment per partner to avoid exhausting their energetic budget too early. Our findings suggest instead that males may be able to enlarge their total reproductive budget, possibly drawing resources from their food gifts by partially feeding on them.

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Ballesteros, Tania M., Mauricio Torres-Mejia et Martha P. Ramírez-Pinilla. « How does diet influence the reproductive seasonality of tropical freshwater fish ? : A case study of a characin in a tropical mountain river ». Neotropical Ichthyology 7, n^o 4 (2009) : 693–700. http://dx.doi.org/10.1590/s1679-62252009000400019.

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Seasonal breeding of tropical freshwater fish may be synchronized with periods of high food consumption. We explored this hypothesis by studying the relationship between diet and reproductive activity of Creagrutus guanes (Teleostei, Characidae). Our results showed that C. guanes had a generalist and omnivorous diet dominated by aquatic insects (mainly Diptera larvae) and seeds. Creagrutus guanes did not show intersexual or ontogenetic variation in diet. Peaks of feeding activity during rainy months were not synchronized with breeding in dry months. Our results do not support the hypothesis that the reproductive season has to be synchronized with high food consumption. We discussed the hypothesis fat reserves may be an important factor for the desynchronization of peaks of feeding and reproduction as explanation of seasonal breeding of this species.

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Villares Junior, GA, LM Gomiero et R. Goitein. « Biological aspects of Schizodon nasutus Kner, 1858 (Characiformes, Anostomidae) in the low Sorocaba river basin, São Paulo state, Brazil ». Brazilian Journal of Biology 71, n^o 3 (août 2011) : 763–70. http://dx.doi.org/10.1590/s1519-69842011000400023.

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Four biological aspects of Schizodon nasutus in the low Sorocaba river basin, São Paulo, Brazil were analysed. These were accomplished during the year seasons. The fish diet and the feeding activity were investigated by studying the repletion index, which showed no significant differences between seasons. The food items analysed by frequency of occurrence and dominance showed a predominance of vegetable items in the diet. The reproduction, analysed by using the gonadosomatic index, indicated that the reproductive period occurs during the summer period when temperatures are higher and rainfalls are more intense. The amount of accumulated fat and condition factor varied according to reproduction, especially for females.

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Rueger, T., T. A. Barbasch, M. Y. L. Wong, M. Srinivasan, G. P. Jones et P. M. Buston. « Reproductive control via the threat of eviction in the clown anemonefish ». Proceedings of the Royal Society B : Biological Sciences 285, n^o 1891 (21 novembre 2018) : 20181295. http://dx.doi.org/10.1098/rspb.2018.1295.

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In social groups, high reproductive skew is predicted to arise when the reproductive output of a group is limited, and dominant individuals can suppress subordinate reproductive efforts. Reproductive suppression is often assumed to occur via overt aggression or the threat of eviction. It is unclear, however, whether the threat of eviction alone is sufficient to induce reproductive restraint by subordinates. Here, we test two assumptions of the restraint model of reproductive skew by investigating whether resource limitation generates reproductive competition and whether the threat of eviction leads to reproductive restraint in the clown anemonefish Amphiprion percula . First, we use a feeding experiment to test whether reproduction is resource limited, which would create an incentive for the dominant pair to suppress subordinate reproduction. We show that the number of eggs laid increased in the population over the study period, but the per cent increase in fed groups was more than twice that in unfed groups (205% and 78%, respectively). Second, we use an eviction experiment to test whether the dominant pair evicts mature subordinates, which would create an incentive for the subordinates to forgo reproduction. We show that mature subordinates are seven times more likely to be evicted than immature subordinates of the same size. In summary, we provide experimental support for the assumptions of the restraint model by showing that resource limitation creates reproductive competition and a credible threat of eviction helps explain why subordinates forego reproduction. Transactional models of reproductive skew may apply well to this and other simple systems.

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David, V. M. M., et B. A. MacDonald. « Seasonal biochemical composition of tissues from Cucumaria frondosa collected in the Bay of Fundy, Canada : feeding activity and reproduction ». Journal of the Marine Biological Association of the United Kingdom 82, n^o 1 (février 2002) : 141–47. http://dx.doi.org/10.1017/s0025315402005258.

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This is the first study to examine the seasonal biochemical composition of tissues from male and female Cucumaria frondosa. Gonad and body wall tissues were analysed for their protein, lipid, and glycogen content. Lipids were the single most abundant component in gonad tissues, followed by proteins and glycogen, for both males and females. However, only protein and glycogen in the gonad tissues differed between feeding and non-feeding periods as well as between pre- and post-spawning periods. Proteins and lipids were both more abundant than glycogen in the body wall tissues. In this case, only protein and glycogen were found to differ between spawning states. All differences observed in the gonad tissues were attributed to the annual reproductive cycle, which produces a need for nutrient storage to allow the production of gametes throughout the year. The body wall was thought to be responsible for the build up of reserves during the feeding period in order to support maintenance and reproduction during non-feeding months.

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Chandran, Divya, Joshua Rickert, Candice Cherk, Bradley R. Dotson et Mary C. Wildermuth. « Host Cell Ploidy Underlying the Fungal Feeding Site Is a Determinant of Powdery Mildew Growth and Reproduction ». Molecular Plant-Microbe Interactions® 26, n^o 5 (mai 2013) : 537–45. http://dx.doi.org/10.1094/mpmi-10-12-0254-r.

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Golovinomyces orontii is an obligate biotrophic powdery mildew (PM) that colonizes Arabidopsis thaliana and agronomic species. It establishes a specialized feeding structure in epidermal cells to fuel its extensive surface hyphal growth and reproduction. Previously, endoreduplication was identified in Arabidopsis mesophyll cells underlying the fungal feeding site, presumably to meet the metabolic demands imposed by the fungus. Furthermore, the cell cycle transcription factor MYB3R4 was shown to regulate this process. Herein, PM-induced endoreduplication is further characterized and three additional factors influencing host ploidy in cells underlying the fungal feeding site are identified. While mutations in PUX2 and PMR6 reduce basal ploidy, mutations in PMR5 (and MYB3R4) abrogate the PM-induced ploidy increase. Moreover, analysis of pmr5 microarray data suggests that PMR5 acts upstream of a MYB3R transcription factor such as MYB3R4 to control PM-induced ploidy. Induced endoreduplication occurs exclusively in mesophyll cells underlying the fungal feeding site at 5 days postinoculation, concomitant with PM reproduction. Gene copy number increases and chromatin remains decondensed, suggesting active, elevated gene expression. Cell ploidy underlying the fungal feeding site is highly correlated with the extent of PM growth and reproduction for these mutants, indicating that (induced) mesophyll cell ploidy is a PM susceptibility determinant.

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Miller, Fredric, et George Ware. « Suitability and Feeding Preference of Selected North American, European, and Asian Elm (Ulmus spp.) Biotypes to Elm Leaf Beetle (Coleoptera : Chrysomelidae) ». Journal of Environmental Horticulture 20, n^o 3 (1 septembre 2002) : 148–54. http://dx.doi.org/10.24266/0738-2898-20.3.148.

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Abstract Recently introduced North American elm cultivars, simple and complex elm hybrids of European and Asian parentage, and simple Asian hybrids of U. pumila and U. japonica parentage growing at The Morton Arboretum, Lisle, IL, were evaluated in laboratory bioassays for ovipositional response, and feeding preference and suitability for larvae and adults of the elm leaf beetle, Xanthogaleruca luteola (Muller). Larval and adult no-choice and adult multiple-choice feeding studies revealed that the North American cultivars of U. americana ‘Jefferson’ and U. americana ‘Valley Forge’, U. americana (diploid form), and U. americana were the least preferred for feeding and reproduction by the elm leaf beetle. Among simple and complex European hybrids, ‘Homestead’, ‘Patriot’, and ‘Prospector’ were least preferred and least suitable for larval development, feeding, and reproduction by adult elm leaf beetles. Hybrids of ‘Frontier’, ‘Pioneer’, and ‘Regal’; the simple Asian hybrids of ‘Cathedral’ and ‘New Horizon’; and U. pumila were more highly preferred for feeding and suitable for reproduction. The least preferred and least suitable North American biotypes of U. x americana ‘Jefferson’, U. americana ‘Valley Forge’, and U. americana (diploid form), simple and complex European hybrids of ‘Homestead’, ‘Patriot’, and ‘Prospector’, show promise for use in areas where the elm leaf beetle is persistent and for future elm breeding programs.

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Hargrove, John W., M. Odwell Muzari et Sinead English. « How maternal investment varies with environmental factors and the age and physiological state of wild tsetse Glossina pallidipes and Glossina morsitans morsitans ». Royal Society Open Science 5, n^o 2 (février 2018) : 171739. http://dx.doi.org/10.1098/rsos.171739.

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Theory suggests females should optimize resource allocation across reproductive bouts to maximize lifetime reproduction, balancing current and future reproductive efforts according to physiological state and projected survival and reproduction. Tests of these ideas focus on long-lived vertebrates: few measure age-related reproductive output in iteroparous invertebrates, or partition reserves between those allocated to offspring versus mothers. We investigated how maternal age, and environmental and physiological factors influence reproductive investment in wild tsetse, Glossina pallidipes Austen and G. morsitans morsitans Westwood. Tsetse provide a tractable system to measure reproductive allocation. Females exhibit high maternal investment, producing single, large offspring that rely exclusively on maternal reserves. We find that mothers in better physiological condition and experiencing cooler temperatures produce larger offspring. Pupal size increases significantly but weakly with age. In both species, females with less fat invest proportionately more in offspring. Post-partum fat decreases in flies with badly frayed wings: poor flight capability may limit their feeding efficiency, or they may sacrifice more reserves as a terminal investment. Our results support evidence that offspring size increases with maternal size, investment depends on the environment, and females with lower chances of future reproduction invest more into current offspring. We discuss the implications of maternal effects for predicting vector population responses to environmental change.

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Alvarenga, Érika R. de, Nilo Bazzoli, Gilmar B. Santos et Elizete Rizzo. « Reproductive biology and feeding of Curimatella lepidura (Eigenmann & ; Eigenmann) (Pisces, Curimatidae) in Juramento reservoir, Minas Gerais, Brazil ». Revista Brasileira de Zoologia 23, n^o 2 (juin 2006) : 314–22. http://dx.doi.org/10.1590/s0101-81752006000200002.

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Reproductive biology and feeding of Curimatella lepidura (Eigenmann & Eigenmann, 1889) were studied in Juramento reservoir, São Francisco River basin, Southeastern Brazil. Histological analyses and gonadosomatic indexes revealed females and males in reproductive activity from October to March and total spawning occurring from January to March coupled with the peak of spermiating males. In the dry season, the fishes accumulated energetic reserves for reproduction during a short rainy season. The species presented sexual dimorphism, being females larger than males and sexual maturation occurring close to 7.7 cm standard length for females and 7.1 cm for males. C. lepidura presented iliophagous feeding habit, ingesting mainly sediment/detritus and a small amount of acari, algae, Tricoptera insects and Ostracoda crustaceans, suggesting a probable role in nutrient recycling of the Juramento reservoir.

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Wells, FE, et JK Keesing. « Reproduction and feeding in the abalone Haliotis roei gray ». Marine and Freshwater Research 40, n^o 2 (1989) : 187. http://dx.doi.org/10.1071/mf9890187.

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H. roei has a short period of intense spawning in July and August, followed by low levels of spawning until December. A few ripe animals are present throughout the year. Males were more common than females in a sample made at Waterman, Western Australia. The animals begin to mature at about 40 mm, but have few gametes at this size. Females of the maximum known size of 122 mm produce an estimated 8.6 million eggs. H. roei is herbivorous, feeding on a variety of macroalgae present in the drift. Algae consumed varied seasonally and between platforms. Volumes of gut contents were greatest in winter, corresponding with the time of maximum food availability.

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Prasad, R. S. « Behavioural analysis of feeding and reproduction in haematophagous insects ». Proceedings : Animal Sciences 94, n^o 3 (juin 1985) : 225–38. http://dx.doi.org/10.1007/bf03186265.

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Sukumar, Kumuda. « Impact of chemicals on feeding and reproduction in insects ». Proceedings : Animal Sciences 96, n^o 3 (mai 1987) : 311–16. http://dx.doi.org/10.1007/bf03180014.

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Liu, Hongbin, Xiaoqin Wu, Yaqi Feng et Lin Rui. « Autophagy contributes to the feeding, reproduction, and mobility of Bursaphelenchus xylophilus at low temperatures ». Acta Biochimica et Biophysica Sinica 51, n^o 8 (17 juillet 2019) : 864–72. http://dx.doi.org/10.1093/abbs/gmz068.

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Abstract The pine wood nematode (PWN), Bursaphelenchus xylophilus, is the pathogen causing pine wilt disease (PWD), which is a devastating forest disease. At present, little is known about the defense mechanisms of the PWN, which limits PWD control. Although autophagy plays an important role in the physiological and pathological processes of eukaryotes, its significance in the PWN remains unknown. In this study, we prepared an anti-BxATG8 polyclonal antibody and identified two PWN autophagy marker proteins: BxATG8-I and BxATG8-II. By western blot analysis, we found that the ratio of BxATG8-II to BxATG8-I, which represents autophagic activity, was decreased significantly when samples were treated with the autophagy inhibitor 3-methyladenine. As such, we were able to successfully detect and quantify autophagic activity in the PWN. Thereafter, we investigated the effects of low and high temperatures on PWN growth and reproduction. The results revealed that feeding rate, reproduction rate, and mobility decreased at 15°C and increased at 35°C. By contrast, autophagic activity was high at 15°C and low at 35°C, suggesting that the PWN regulates autophagic activity in response to changes in temperature to maintain physiological homeostasis. When autophagy was inhibited at 15°C, feeding rate, reproductive rate, and mobility declined further, indicating that autophagy is crucial for PWN growth and reproduction at low temperature. These results indicate that autophagy in the PWN is an important response mechanism to temperature changes.

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