Dissertations / Theses: 'Animal Sex Behavior'

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Schwartz, Brian A. "Sex-specific investment in incubation and the reproductive biology of two tropical antbird." [Missoula, Mont.] : The University of Montana, 2008. http://etd.lib.umt.edu/theses/available/etd-05072008-151032/unrestricted/MSc_Thesis_Brian_A._Schwartz2008.docx.

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Garbarino, Eduardo Jose. "Effect of lameness on ovarian activity in post-partum holstein cows." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004822.

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Thesis (M.S.)--University of Florida, 2004.
Typescript. Title from title page of source document. Document formatted into pages; contains 108 pages. Includes Vita. Includes bibliographical references.

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Field, Evelyn F., and University of Lethbridge Faculty of Arts and Science. "Sex differences in movement organization II : the organization of sex differences in movement during food protection, contact righting, skilled reaching and vertical exploration in the rat : the role of gonadal steroids, body morphology, and the central nervous system." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2006, 2006. http://hdl.handle.net/10133/14.

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Whether there are sex differences in the kinematic organization of non-reproductive behaviors is rarely addressed. In this thesis, evidence is presented that male and female rats organize their posture and stepping differently during a food protection task, contact righting, skilled reaching, and vertical rearing. Neonatal gonadal steroid exposure can alter sex-typical patterns of movement organization. Whether these differences are due to sex differences in body morphology or central nervous system (CNS) was also addressed using gravid females and tfm males. The results reveal that sex differences in movement are CNS based. Furthermore, the expression and choice of sex-typical patterns of movement can be altered by CNS injury. Finally, evidence is presented that sex differences in movement organization are also present in marsupials and insects. The implications of these results for our understanding of the evolution of sex differences in CNS anatomy and behavior will be discussed.
xvi, 249 leaves : ill. ; 28 cm.

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Cyrenne, De-Laine. "Developmental and sex differences in responses to novel objects : an exploration of animal models of sensation seeking behaviour." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/2550.

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Human adolescents exhibit higher levels of sensation seeking behaviour than younger or older individuals, and sensation seeking is higher in males than females from adolescence onwards. Data suggest that changes in gonadal hormone levels during adolescence and differences in the dopamine neurotransmitter system are the bases for why some people exhibit sensation seeking behaviour while others do not. However, causal relationships between physiology and behaviour have been difficult to establish in humans. In order to explore the physiological influences on novelty-seeking behaviour, we looked at response to novelty in a laboratory rodent. This research examined responses to novelty in the conditioned place preference (CPP) task and the novel object recognition (NOR) task in Lister-hooded rats, and assessed the benefits and limitations of each methodology. While the CPP task was not found to provide a reliable measure of response to novelty, the NOR task was more successful. In order to understand the ontogeny of sex differences in novelty responses, both males and females were tested from adolescence through to adulthood. While no sex difference was found in adults in the NOR test, mid-adolescent males exhibited higher novelty preference behaviour than either younger or older males, or females at each stage of development. Since gonadal hormones levels rise during adolescence, a pharmacological agent (a gonadotrophin-releasing hormone antagonist) was used to suppress gonadal hormone levels from early adolescence before again examining responses on the NOR test at mid-adolescence. Gonadal hormone suppression from early adolescence onwards eliminated the sex difference in the NOR test at mid-adolescence by reducing the male response to novelty, while no difference was measured in the female animals. These findings suggest that gonadal hormones play a significant role in the development of response to novelty, especially in males, and the implications for our understanding of human sensation-seeking behaviour are discussed.

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Tulloch, Bridget. "The effects of relatedness, social contact, and sex on observational learning in rats (Rattus norvegicus)." The University of Waikato, 2007. http://hdl.handle.net/10289/2468.

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Kin recognition is the ability to identify a conspecific as a relative and can occur even when animals are complete strangers. By being able to recognise relatives, animals are able to give preferential treatment to those with which they share genes. Recognition may occur by either direct familiarisation (learning a phenotypic cue that reliably correlates to kinship), or by indirect familiarisation (learning kinship relationships through previous encounters). Rats (Rattus norvegicus) can recognise kin, however to what degree kin recognition is mediated by genetics (direct familiarisation) or social relationships (indirect familiarisation) are unknown; the influences of kinship and familiarity on the ability to learn from a conspecific is also unknown. Furthermore, the sex of an animal can also influence its ability to learn but this effect has received little attention in the literature, particularly when considering observational learning tasks. I assessed if relatedness and/or familiarity influenced a rat's ability to learn through observation, and if gender relationships influence the learning process. Eighty rats ( observers ) were given the opportunity to observe a demonstrator rat press a joystick in a given direction to obtain a food reward. Observers watched a demonstrator that had one of the following relationships with them: related and familiar, related and unfamiliar, unrelated and familiar, or unrelated and unfamiliar. When observers were given the opportunity to manipulate the joystick, the number of sniffs of the joystick, the latency to first move the joystick and the total number of presses were recorded. Rats that were both familiar and related to the demonstrator consistently performed better than any other treatment group; furthermore, rats that were familiar with the demonstrator performed the task more efficiently than rats that were not familiar with the demonstrator. When the demonstrators and observers were related, the observers produced more presses and sniffs of the joystick while having a lower latency to the first push In addition, male observers learnt better than females regardless of the demonstrator sex, with males that were familiar to their demonstrator making nearly twice as many pushes than any other treatment group. The results from this study are discussed in relation to both the mechanisms of direct and indirect recognition and the potential adaptive value on kin discrimination in the learning process. The home range hypothesis may explain why gender differences in learning were found: male rats have larger home ranges than females. Male rat will regularly encounter more rats than females and would need to ascertain if unfamiliar individuals are relatives. Females remain closer to natal sites and as such are more likely to encounter kin and therefore may not need as well as developed kin recognition ability.

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Augustsson, Hanna. "Ethoexperimental studies of behaviour in wild and laboratory mice : risk assessment, emotional reactivity and animal welfare /." Uppsala : Dept. of Large Animal Clinical Sciences, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/v174.pdf.

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Dayger, Forbes Catherine Anne. "Why Do Animals Do What They Do, When They Do It? Characterizing the Role of the Hypothalamus-Pituitary-Adrenal Axis in Seasonal Life-History Transitions." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3614.

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Resource availability follows seasonal cycles in environmental conditions. To align physiology and behavior with prevailing environmental conditions, seasonal animals integrate cues from the environment with their internal state. One of the systems animals use to integrate those cues is the hypothalamus-pituitary-adrenal (HPA) axis and its primary effector, glucocorticoid hormones. The HPA axis has wide-ranging effects on physiology and behavior and, in the context of a glucocorticoid stress response, is known to mediate tradeoffs between immediate survival and future fitness. The HPA axis also plays an important role in facilitating predictable life-history events. Variation in HPA axis activity has been reported in all vertebrates, often coordinating seasonal reproduction and possibly also transitions between life-history stages. My dissertation research used red-sided garter snakes (Thamnophis sirtalis parietalis) to examine the role of the HPA axis in regulating seasonal life-history transitions, especially in females. In Chapter 2, I hypothesized that seasonal plasticity in stress responses is regulated, in part, by changes in the responsiveness of the adrenal glands to adrenocorticotropic hormone (ACTH). I found that glucocorticoid responses to ACTH challenge were smaller in males than in females during the spring, suggesting that reports of reduced stress responsiveness in males may reflect lower adrenal responsiveness to ACTH. The sex difference in mating season duration and consequently also in the timing of migration led me to hypothesize that sex differences in HPA axis activity could explain sex differences in the timing of migration. Furthermore, adrenal responsiveness to ACTH also varied seasonally in males, but not females, suggesting that female stress responses, which have not been studied, may not vary seasonally. In Chapter 3, I investigated potential seasonal variation in female stress responses, which have not previously been examined. In males, baseline glucocorticoids decrease over the course of the mating season resulting in significantly lower baseline levels in males that have begun to migrate. I hypothesized that a change in HPA axis activity occurs during spring and fall migration. Peak stress-induced glucocorticoid concentration occurred at an earlier sampling time in females during the spring compared to the fall. Peak stress-induced glucocorticoid concentrations also occurred at a later sampling time in migrating females than in pre-migratory females during the spring, suggesting that negative feedback regulation of the HPA axis changes as soon as females begin to migrate during the spring. Female red-sided garter snakes are biennial breeders that give birth approximately every other year implying that a female's recent reproductive history can influence whether or not she will reproduce in a given year. Body condition can be used as a proxy for recent reproductive history and can be related to baseline and stress-induced glucocorticoid concentrations. In Chapter 4, I hypothesized that hormonal and behavioral stress responses vary with body condition. Baseline glucocorticoids did not vary with body condition, but females in low body condition showed a significantly larger increase in plasma glucocorticoids in response to capture stress. Body condition, but not capture stress, influenced latency to copulate, suggesting that females are resistant to the behavioral effects of capture stress during the spring mating season. Only females in low body condition increased latency to copulate in response to injection of a physiological (15 µg) dose of exogenous CORT, while all females responded to a pharmacological (60 µg) dose, indicating that behavioral responses to exogenous glucocorticoids vary with female body condition. These data suggest that variation in body condition may be associated with differences in HPA axis sensitivity and/or glucocorticoid receptor (GR) density in the brain. I directly tested if there is a relationship among body condition, reproductive history and HPA axis activity in Chapter 5. I found that glucocorticoid stress responses and mating behavior did not vary with body condition, nor was body condition related to brain GR or reproductive condition (parturient vs post-parturient females). Only unreceptive females showed a significant stress-induced increase in glucocorticoids, suggesting that reduced stress responsiveness is associated with receptivity. Parturient females mated faster (were more proceptive) than post-parturient females. These data suggest that HPA axis activity influences reproductive "decisions" by modulating receptivity, while proceptivity is related primarily to recent reproductive history. Together, these chapters help characterize how HPA axis activity varies with season, sex, reproductive history and migration status. By systematically probing the HPA axis in a single, tractable system, I have gained insight into how changes in the HPA axis support and modulate transitions between life-history stages. These results highlight the HPA axis' important function in mediating the critical trade-offs all animals must navigate to be successful in a changing world.

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Rodgers, Edmund W. "Sexual plasticity in a marine goby (Lythrypnus dalli) social, endocrine, and genetic influences on functional sex /." unrestricted, 2007. http://etd.gsu.edu/theses/available/etd-12022007-220715/.

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Thesis (Ph. D.)--Georgia State University, 2007.
Title from file title page. Mattew S Grober, committee chair; Kim Wallen, Charles Derby, Laura Carruth, Tim Bartness, committee members. Electronic text (107 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Jan. 31, 2008. Includes bibliographical references. (p. 94-107)

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Rhen, Turk Eleazar. "Effects of embryonic temperature, gonadal sex, and sex steroids on behavior and neuroendocrine phenotype in leopard gecko, Eublepharis macularius /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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Hannula, Gustaf. "Monkey see, monkey do? An intercultural exploration of the dynamics between humans and non-human primates in a professional animal research setting." Scholarly Commons, 2007. https://scholarlycommons.pacific.edu/uop_etds/677.

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This thesis is an exploration of the perceptions of a group of humans in interaction with a group of non-human primates in a professional animal research setting. The study is a novel investigation in the field of intercultural relations, exploring the values and beliefs of a group of research employees, and the intercultural competence and sensitivity these employees model in their interactions with the animals they work with. A focus group was conducted at the Oregon National Primate Research Center and 8 individuals working with non-human primates were interviewed. They were asked a series of 15 open-ended questions in order to explore their identification and appreciation of cultural differences, as well as their general strategies for adapting to cultural difference in the context of an animal research setting. The results of this meeting reflect a range of perceptions, attitudes, and beliefs relative to culture and the possibility of an intercultural relationship between species.

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Carminatti, Marina de Oliveira Ferraz. "Efeitos da paridade da mãe e do sexo do filhote sobre o estilo de cuidado materno e desenvolvimento de filhotes de macacos-prego (cebus sp)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-08122009-095236/.

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Dentre os mamíferos, a ordem Primates é caracterizada por uma gestação longa e, normalmente, nascimento de um único filhote por período reprodutivo. Ainda assim, as fêmeas primatas dão a luz a filhotes pouco desenvolvidos, que requerem grande investimento parental, realizado principalmente por elas. O prolongado período pós-parto, em que o filhote depende integralmente de seu cuidador para alimentação, transporte e proteção, é chamado de infância e perdura até o momento em que o indivíduo é capaz de sobreviver sozinho. Nesse período é possível observar o estilo de cuidado materno, medido através do investimento da mãe em cuidados para seu filhote. É nesse mesmo período que as relações afetivas entre mãe e filhote e com os outros membros do grupo são estabelecidas. Em algumas espécies de mamíferos, incluindo primatas, há diferença entre o investimento materno das mães em relação ao sexo do filhote ou a paridade e posição hierárquica delas. Nesse trabalho, verifiquei o efeito da paridade da mãe e do sexo do filhote sobre o estilo de cuidado materno e desenvolvimento físico e social dos filhotes de um grupo semi-livre de macacos-prego. Além disso, a presente pesquisa deu continuidade a um estudo anterior, com o mesmo grupo, também sobre estilo de cuidado materno e desenvolvimento dos filhotes. Assim, também foi objetivo deste trabalho comparar estas variáveis em função de mudanças na demografia do grupo e nas condições ambientais. Os dados foram coletados no Parque Ecológico do Tietê entre setembro de 2006 e abril de 2008, através dos métodos de animal-focal e todas as ocorrências, e analisados através de análises de agrupamentos e de variância. O estilo de cuidado materno parece estar relacionado com a paridade da mãe, mães primíparas têm maior investimento, de maneira geral, em amamentação, transporte e manutenção da proximidade de seus filhotes, enquanto multíparas investem mais em catação, mas as diferenças não foram significativas. O desenvolvimento físico e social dos filhotes não foi afetado pela mudança na demografia do grupo, mas sim pela mudança das condições ambientais. Uma alteração na disponibilidade do alimento provisionado provocou aumento nas taxas de locomoção do grupo em busca de alimento. O aumento na distância entre mães e filhotes também foi observado e esteve relacionado ao crescimento das redes familiares que promovem a proteção do filhote por indivíduos aparentados que não somente suas mães. O investimento materno foi maior em filhotes machos. Quanto ao desenvolvimento, filhotes fêmeas se alimentaram e se locomoveram independentemente mais que filhotes machos, ainda que a locomoção independente tenha sido maior para machos no início do desenvolvimento. Filhotes fêmeas, no entanto, mantiveram relações de proximidade mais fortes com a mãe e com os outros membros do grupo. O maior investimento materno em machos, independente da paridade das mães, é esperado em populações de primatas em que a oferta de alimento não é limitante do sucesso reprodutivo das fêmeas e em que, portanto, o sexo com maior variabilidade de sucesso reprodutivo em função de habilidades competitivas é o masculino.
In comparison with other mammals, the order Primates is characterized by a prolonged gestation and by the birth of a single offspring in each reproductive period. Besides, female primates give birth to very immature infants that require great parental investment performed mainly by the mothers. Infancy is the post-partum period in which the young is completely dependent on its care-giver for feeding, transportation and protection, and lasts up until the individual is capable of surviving on its own. During this period we can observe the style of maternal care by measuring the mothers investment in care given to her offspring. The affiliative relationship between the infant and its mother, as well as with other members of the social group are established throughout this same period. In some mammal species, including primates, maternal care can differ according to the sex of the infant, and on female parity and hierarchical position. In this study I investigate the effect of mothers parity and on infants sex on the style of maternal care and on the physical and social development of the offspring in a group of semi-free tufted capuchin monkeys. Furthermore, this research followed a previous study, carried out with the same group of monkeys, also regarding the style of maternal care and development of young. Therefore it is also the goal of this study to compare these variables considering differences in group demography and in the environmental conditions between the two study periods. Data were collected at Parque Ecológico do Tietê from September 2006 to April 2008. Data were collect through focal-animal and all occurrences methods, and analyzed by cluster and variance analysis. The style of maternal care seems to be related to the parity of the mother. Primiparous mothers generally invest more in nursing, transportation and in maintaining proximity with their offspring while multiparous mothers invest more in grooming. However the differences were not statistically significant. The physical and social development of the young were not affected by the demographic changes undergone by the group, but were, on the other hand, affected by changes in environmental conditions. An alteration in the availability of provisioned food resulted in an increase in the rate of locomotion of the group in search for food. An increase in the distance between mother and offspring was also noted and was related to the growth of family networks, leading to the protection of the young by kin related individuals besides their mother. There was greater maternal investment in male infants. Regarding infant development, female infants had higher frequencies of independent feeding and locomotion than male infants, even though independent locomotion was greater for males at the beginning of their development. Female infants also maintained greater proximity with their mothers and with other members of the group than male infants. A greater maternal investment in male offspring, independent of the parity of mothers, is expected in primate populations living in areas where food supply is not limiting of females reproductive success, which is the case of the study area, because in such populations males present greater variability than females in reproductive success.

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Smith, Diane Lauren. "Penguin parenting : assortative mating, nest attendance and sex-specific chick provisioning in the African Penguin (Spheniscus demersus)." Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/d1019993.

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Animal behaviour is especially sensitive to environmental variability and prey availability during the breeding season, and this is particularly true for non-volant, central place foragers such as the endangered African Penguin (Spheniscus demersus). Individual sex and morphology, as well as the level of assortment within mated pairs can influence both the behaviour and the reproductive success of species exhibiting biparental care. This study made use of a large biometric database and nest attendance video footage to determine the influence of intrinsic (assortative mating, brood size and chick age) and extrinsic (environmental conditions, anthropic disturbance) factors on breeding behaviour and performance of African Penguins on Bird Island, Algoa Bay, during peak breeding (March - July) in 2013. While sexual dimorphism in African Penguins is subtle, the colony-specific discriminant functions presented here provide an accurate sexing tool when only bill and flipper length are available. Despite the premise that selection of a large, high-quality mate in this longlived, monogamous seabird governs lifetime fitness, only low levels of assortative mating were found, and this only for earlier breeders, when larger females (but not males) bred. The 2013 season was a particularly successful one, coinciding with above-average sardine and anchovy abundance, and almost 80 percent of monitored nests were double-brooded, with very low levels of mortality. A- and B-chicks of double broods and singleton chicks grew at similar rates and exhibited similar body condition indices. In these conditions, chick developmental rates were independent of parental size, assortment or provisioning behaviour. Females raising a double brood were significantly lighter and in poorer body condition than those raising a single chick, although the same trend was not evident in males. Offspring sex ratio in 2013 (2.27:1) favoured male chicks, suggesting that there is potential to over-produce the larger sex when resources are plentiful. Peak nest arrival and departure times of parents did not change over the course of monitored breeding attempts (March-June), nor were they different for disturbed and undisturbed nests or for a single or double brood. The increase in CCTV-observed provisioning rate as chicks grew larger was best explained by brood size, at-sea chlorophyll a concentration, and maximum air temperature, but was unrelated to parental morphology or assortative index. Importantly, parental absenteeism commenced earlier and was markedly greater in nests frequently handled by researchers than in undisturbed nests. Both the time spent together by parents, and absenteeism were measurably affected by maximum afternoon air temperatures, the effects of which are expected to be exacerbated by poorer foraging conditions and climate change. A third of manually-monitored nests shared chick-guarding duties unequally, although this phenomenon was independent of parental sex or morphology. The adaptive benefits of mating patterns and division of labour during chick-rearing may only become apparent in a year of below-average food availability and it is highly recommended that this study be repeated in a year of scarce food resources. These findings augment past foraging ecology studies and demonstrate that investigator disturbance and environmental conditions can affect the nesting behaviour of this highly threatened seabird.

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Thompson, Cynthia L. "Sex, Aggression, and Affiliation: The Social System of White-faced Saki Monkeys (Pithecia pithecia)." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1303399136.

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Dean, Ben. "The at-sea behaviour of the Manx shearwater." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:3dc27434-100c-4fcc-a636-04538c676dc2.

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Seabirds are vulnerable to a wide range of impacts at sea and function as important indicators of ocean health. A detailed understanding of their movements and distributions at sea, as well as the types of behaviour in which they engage and the extent to which those activities make them vulnerable to different impacts is critical in effective conservation planning. But their elusive lifestyles and mobility have hampered studies of their at-sea behaviour. Using miniature data loggers deployed on Manx shearwaters Puffinus puffinus this thesis explores the movements, distribution and behaviour of a small-medium pelagic, procellariiform seabird during foraging trips at sea. Foraging distributions were most variable during the pre-laying period when females departed the colony to build their egg. Females foraged close to the colony when local resources were adequate, but more typically foraged in distant shelf edge waters. Males returned frequently to the colony during this period and typically foraged close by, but also in shelf edge waters when local resources were poor. During incubation and chick-rearing the foraging movements of birds tracked from up to four colonies showed considerable inter-annual variability, but were largely constrained to the Irish and Celtic Seas and the inshore waters of west Scotland. Birds from each of the colonies foraged in waters local to their own colony, but also in more distant locations, including the productive Western Irish Sea and Western Irish Sea Front where birds from multiple colonies co-foraged, presumably at high densities. At-sea behaviour was organized into three principal activities representing: (1) sustained direct flight, (2) sitting on the sea surface, and (3) foraging, comprising tortuous flight interspersed with periods of immersion and diving in pursuit of prey. Foraging was highly constrained to daylight hours during which birds engaged in bouts of diving separated by periods of flight or rest on the surface. Most dives were up to 6 m deep, lasting up to 13 s, but some much deeper dives (maximum 55.5 m) were also made. During chick-rearing the use of short and long duration trips may allow parents to control provisioning effort and their own body condition. However, reducing parents’ requirement to provision their chick (by supplemental chick feeding) did not appear to alter the at-sea movements and behaviour of parents, suggesting that at-sea behaviour probably is controlled more by foraging conditions and prey distributions than by the nutritional demands of the chick.

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Okuyama, Junichi. "Study on conservation and enhancement of endangered sea turtles using animal behavioral information." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/135982.

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Odén, Kristina. "Fear and aggression in large flocks of laying hens : effects of sex composition /." Skara : Dept. of Animal Environment and Health, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/v144.pdf.

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Pascual, Sala Jordi. "About eating and not eaten. Vigilance and foraging strategies in wintering Eurasian siskins (Carduelis spinus) = Sobre menjar i no ser menjar: estratègies de vigilància i alimentació en lluers hivernants (Carduelis spinus)." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/128917.

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Animals have to eat a certain amount of food every day to survive. Since trophic resources are usually found in exposed locations, animals are in risk of predation while feeding, and face the well known trade-off between predation and starvation risks. Animals may reduce predation risk by scanning for predators. However, an increase in vigilance entails an increase in exposure time to predators. Therefore, animals may increase food intake to reduce foraging bouts at the cost of vigilance or may do the opposite. Animals may also reduce predation risk without increasing vigilance by joining groups. However, when food items are concentrated in some defendable patches, individuals will fight to access them, leading to interference competition. Birds have developed different vigilance and foraging strategies to cope with all these trade-offs. These strategies can be adapted to the environmental conditions and type of predators, and will highly differ according to the genetic, phenotypic and ecological characters of the individuals. In this thesis I investigated how wintering Eurasian siskins (Carduelis spinus) adjusted their vigilance and foraging behaviour to predation risk and competition, and how this adjustment varied according to conspicuousness, residence status and personality of focal birds. I also studied how resident and transient siskins regulated their body mass to predation risk. In order to determine the differential effects of predation risk and competition on the behaviour of siskins, I designed an experiment with three feeders differing in predation risk and interference competition. I captured the siskins every week and marked them with aluminium rings (at first capture) and colour rings (if residents). From each bird, I measured body mass, wing length and plumage coloration cues. I filmed the siskins foraging at feeders from a hide. Then I analyzed the video recordings and selected a sample of birds at each feeder to study the effect of environmental factors, and selected pairs of birds belonging to different cohorts of sex, residence and personality to compare their vigilance and foraging behaviour. I also compared body mass of a large sample of residents and transients in two periods with and without avian predators. I found that siskins adjusted their vigilance behaviour specifically to the environmental conditions. Vigilance to predators, achieved by reducing inter-scan durations, was less costly in terms of food intake rate than vigilance to flockmates, achieved by increasing scan durations. Siskin males were more brightly coloured and detectable than females, and showed a vigilance system more oriented to predator detection, supporting (together with the correlation between coloration and vigilance in males) the view of a predation cost to conspicuousness. Resident and transient siskins showed a different vigilance and foraging strategy. Residents were more confident in vigilance to reduce predation risk while transients preferred to reduce foraging bout lengths. Transient siskins were in higher predation risk because of their vigilance and foraging behaviour, and this was related both to their unfamiliarity with the area and their subordination to residents. Proactive male siskins showed a vigilance system that improved their ability to detect predators as compared with reactive males, supporting the view of a behavioural compensation for their personality trait (and not the existence of behavioural carryovers). Resident siskin males adjusted their body mass to the presence of predators at the foraging area, something that transients could not do because of their site unfamiliarity. In general, dominant individuals (whether males, residents or proactive birds) showed a foraging behaviour that prioritized the reduction in predation risk and not the increase in food intake rate, as compared to subordinates. Dominance alone cannot account for our results, although it probably had some effect in all the comparisons.
En aquesta tesi vaig estudiar el comportament de vigilància i d'alimentació de lluers hivernants a tres menjadores que diferien en risc de depredació i competència. Vaig determinar com els ocells ajustaven la vigilància a aquestes variables, i vaig comparar el comportament dels ocells pertanyents a diferents classes de sexe, estatus de residència i personalitat, per veure si adoptaven diferents estratègies. Els lluers van ajustar de manera diferent el seu comportament al risc de depredació i la competència. La vigilància dirigida als depredadors, assolida tot reduint la durada dels intervals entre vigilàncies, va resultar ser menys costosa en termes d'ingesta d'aliment que la vigilància a companys d'estol, assolida mitjançant l'increment de la durada de les vigilàncies. Els mascles de lluer van ser més brillants i fàcils de detectar que les femelles, i van mostrar un comportament més orientat a la detecció de depredadors, cosa que dóna suport (junt amb la correlació entre coloració i vigilància en mascles) a l'existència d'un cost de depredació associat a la conspicuïtat del plomatge. Els lluers residents van adoptar un sistema de vigilància que els exposava a menor risc de depredació que els transeünts. A més, a diferència d'aquests, van confiar sobretot en la vigilància a l'hora de reduir el risc de depredació. Aquestes diferències estarien relacionades tant amb el grau de coneixement de la zona com amb la dominància. Els mascles proactius van mostrar un sistema de vigilància que millorava la seva capacitat per detectar aviat els depredadors en comparació amb els mascles reactius, cosa que dóna suport a la idea d'una compensació comportamental del tret de personalitat. Els mascles residents van ajustar la seva massa corporal a la presència d'un depredador aeri a la zona, cosa que no van fer els transeünts segurament pel seu desconeixement del risc de depredació. En general, els individus dominants (mascles, residents o individus proactius) van mostrar un comportament d'alimentació que prioritzava la reducció del risc de depredació i no l'increment en la ingesta d'aliment. La dominància per sí sola no pot explicar els resultats de les comparacions, malgrat que pot tenir un cert efecte en totes elles.

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18

Vizzotto, Elissa Forgiarini. "Comportamento animal e atributos fisiológicos de vacas leiteiras submetidas a ambientes com e sem sombreamento durante a estação quente." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/101658.

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O ambiente físico tem grande importância na fisiologia do animal, influenciando a reprodução e produção. Com as mudanças climáticas e o melhoramento genético dos animais, com ênfase no aumento da produtividade por animal, os animais passaram a sofrer mais com as altas temperaturas, alterando seu comportamento e seu bem estar. O objetivo deste trabalho foi avaliar o comportamento social e ingestivo e atributos fisiológicos de vacas leiteiras durante a estação quente, com ou sem acesso à sombra. O estudo foi conduzido em Lages, SC, utilizando 14 vacas lactantes em pastejo, as quais foram divididas em dois grupos, permanecendo um grupo somente no sol sem acesso à sombra e o outro em ambiente com sombreamento. Foram observados os comportamentos ingestivo e social dos animais das 07:30 ( GMT -2:00) às 23:00h (GMT-2:00), em intervalos de 10 minutos, totalizando 650min. As frequências respiratória e cardíaca, temperatura corporal das vacas e número de movimentos ruminais foram avaliados diariamente. Os dados do comportamento animal foram previamente padronizados e posteriormente, submetidos à análise multivariada, incluindo as análises de fatores principais de agrupamento, avaliação das variáveis que determinaram os agrupamentos por análise discriminante e canônica, utilizando o programa estatístico SAS 9.2. Os grupos diferiram principalmente quanto ao número de eventos de ingestão de água, competição por sombra e número de interações agressivas, aos tempos despendidos em ócio total, ócio em pé, de permanência perto do bebedouro, frequência respiratória e cardíaca, temperatura corporal, número de movimentos ruminais, escores de ofegação às 15 (GMT -2:00) e às 19 (GMT -2:00) horas e tolerância ao calor. No entanto os grupos de animais não diferiram quanto aos tempos gastos caminhando de cabeça alta, caminhando de cabeça baixa, em estação, número de eventos de competição por água no bebedor e os dados zootécnicos de dias em lactação, ordem de parto e produção de leiteira. O fornecimento de sombra na área de pastejo mesmo em condições moderadas de estresse térmico alterou positivamente os atributos fisiológicos e comportamentais. A severidade do estresse, percebida pela alteração dos atributos fisiológicos, alterou distintamente o comportamento social e ingestivo.
The physical environment, has a great importance on animal physiology affecting breeding and production. Due to climate change and animal breeding, which enphasizes higher production per animal, animals might get heat stressed from high temperatures, changing their behavior and their welfare. This study was performed to assess the social and feeding behavior and physiological attributes of dairy cows during the warm season with or without access to shade. The study was conducted in Lages, SC, using 14 lactating cows at grazing. These animals were divided into two groups, one group remained under the sunlight, without access to shade, while the other group was kept in shade-provided environment. Ingestive and social behavior of animals was observed from 7:30 (GMT -2:00) to 23:00 (GMT -2:00), registered at 10-minutes interval totaling 650 minutes. Respiratory and heart rate, body temperature and number of ruminal movements were assessed daily. The data of animal behavior were standardized using the standard procedure and then were subjected to multivariate analysis, including the analysis of key factors (PROC FACTOR), cluster analysis (PROC FATSCLUSTER AND PROC CLUSTER), evaluation of variables that determined groups by discriminant analysis and canonical, using SAS 9.2 statistical software. The groups differed mainly on the number of events of swallowing water, shade and competition for number of aggressive interactions, the time spent in complete idleness, loitering foot, staying near the water cooler, respiratory and heart rate, body temperature, number of ruminal movements, panting scores at 15 (GMT-2:00) and 9 (GMT-2:00) hours, heat tolerance. However animal groups did not differ regarding time spent walking head high, walking head down, season, number of events per water drinker and competition in the production data of days in milk, parity order and production of milk. The provision of shade in the paddocks, even under moderate heat stress, altered positively physiological and behavioral attributes. The stress severity, noticed by the change of physiological attributes, changed distinctly social and feeding behavior.

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19

Thalluri, Rajaa. "Assessment of Cognitive Deficits and Sex Differences in Adult Rats after Adolescent Methylphenidate Exposure." Kent State University Honors College / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1462516537.

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20

Wilson, Megan L. "An investigation into the factors that affect play fighting behavior in giant pandas." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-05032005-110217/.

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Thesis (Ph. D.)--Psychology, Georgia Institute of Technology, 2006.
Terry Maple, Committee Chair ; M. Jackson Marr, Committee Member ; Rebecca Snyder, Committee Member ; Marc Weissburg, Committee Member ; Paul Corballis, Committee Member ; Roger Bakeman, Committee Member.

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21

Chu, Joanne Chen. "The effects of acoustic signals and sex steroids on dopaminergic function in male anurans /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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22

Bang, H. Helen (He Won Helen) 1974. "The distribution of a water strider, Aquarius remigis, among habitat patches explained by sex specific dispersal strategies /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29413.

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A survey of a natural population of Aquarius remigis, a stream dwelling water strider, living in East Turkey Creek, Arizona, USA, revealed that they were mostly found in either pairs consisting of one male and one female, or in small female biased groups. Chi-squared analysis confirmed that this finding was not due to random chance. The sex ratios were manipulated to further test this observation, that is, that the water striders would return to the most commonly observed sex ratio combinations even after being deliberately rearranged. Pairs of water striders or female biased sex ratios were observed in the experimental pools after a 24 hour period. Behavioural experiments conducted in the laboratory were performed to investigate the possible behavioural interactions that could influence the sex ratios observed in the field. Artificial pools with three water striders, in four sex ratio combinations, and four water striders, in five sex ratio combinations, were used. (Abstract shortened by UMI.)

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23

Santos, Lucas Peternelli Correa dos. "Diferenças sexo/etárias no Forrageamento de Cebus nigritus em área de Mata Atlântica." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-19032010-143949/.

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Após anos do estudo moderno da ecologia e comportamento dos primatas, a juventude, definida como o período entre o desmame e a maturidade sexual, permanece sendo uma das fases menos compreendidas do ciclo de vida destes animais. Existem quatro teorias gerais para explicar os padrões de forrageamento e escolha da dieta de primatas juvenis. A primeira afirma que os juvenis adotam uma estratégia de aversão ao risco, evitando a competição por alimento, a segunda, que os padrões alimentares dos imaturos serão determinados pelas oportunidades de observação de outros indivíduos do grupo, a terceira afirma que as diferenças nos padrões alimentares entre imaturos e adultos se dão em virtude da falta de força e habilidade desses indivíduos para explorar recursos de difícil acesso e a quarta afirma que jovens e adultos exploram diferentes itens com base na demanda nutricional associada aos custos de crescimento cerebral e do corpo. O presente trabalho teve por objetivo investigar diferenças sexo/etárias nos padrões comportamentais e alimentares de um grupo de Cebus nigritus selvagem em uma área de Mata Atlântica no Parque Estadual Carlos Botelho, com enfoque nos imaturos, em especial nos juvenis, à luz das quatro teorias. Os resultados mostraram que as fêmeas e os infantes preferem frutos que são ricos em carboidratos, os machos preferem as folhas, que são um recurso abundante, enquanto os jovens preferem os invertebrados que são importantes fontes de proteínas e gordura. O comportamento alimentar dos jovens no PECB foi mais bem explicado pela teoria da demanda nutricional para crescimento do cérebro e corpo, mas alguns resultados também apóiam as teorias de aversão ao risco e oportunidade de aprendizagem.
After years of modern study of ecology and behavior of primates, juvenility, defined as the period between weaning and sexual maturity, remains one of the least understood stages of the life cycle of these animals. There are four general theories to explain the foraging patterns and diet choice in young primates. The first states that juveniles adopt a strategy of risk aversion, avoiding competition for food. The second states that the feeding patterns of immature will be determined by different opportunities for observational learning of other individuals in the group. The third states that the differences in feeding patterns between immature and adults is due to the lack of strength and ability of immature individuals to exploit difficult to access resources. The fourth states that young explore various items based on the nutrient demand associated with the costs of brain growth and body. This study aimed to investigate age/sex differences in feeding and foraging patterns of a group of Cebus nigritus wild in an area of Atlantic Forest in the Parque Estadual Carlos Botelho, focusing on immatures, especially in juveniles, in the light of four theories. The results showed that females and infants prefer fruits that are rich in carbohydrates, males prefer the leaves, which are an abundant resource, while young prefer the invertebrates, that are important sources of protein and fat. The feeding behavior of young PECB was best explained by the theory of nutrient requirements for growth of the brain and body, but some results also support theories of risk aversion and learning opportunity.

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Gustafsson, Lisa. "Endogenous Opioids and Voluntary Ethanol Drinking : Consequences of Postnatal Environmental Influences in Rats." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7776.

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25

Mays, Nora Ann 1952. "Hormonal correlates of reproductive behavior in the cooperatively breeding Harris' hawk (Parabuteo unicinctus)." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277088.

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

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Castro, André Luis da Silva [UNESP]. "Efeito de estímulos visuais e químicos do sexo oposto na reprodução da tilápia-do-Nilo." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/144153.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A reprodução dos peixes é regulada pelo eixo hipotálamo-hipófise-gônadas. As interações entre machos e fêmeas podem afetar esse eixo, desencadeando respostas fisiológicas, como a secreção de hormônios reprodutivos e o desenvolvimento das gônadas, e comportamentais, como corte, perseguição, desova e espermiação nos membros participantes. Dessa forma, a comunicação visual e química com um peixe do sexo oposto pode modular a reprodução. O objetivo deste trabalho foi testar o efeito da comunicação visual e química com o sexo oposto na reprodução da tilápia-do-Nilo. Para isso, quatorze casais de tilápia-do-Nilo foram mantidos em cada uma das seguintes condições, que variaram apenas quanto ao tipo de comunicação permitida entre o casal: 1) comunicação visual; 2) comunicação química; 3) comunicação química e visual; 4) isolados (sem qualquer contato entre o casal). O comportamento reprodutivo e o desenvolvimento das gônadas dos machos e fêmeas foram analisados e comparados entre as condições. A comunicação visual com o peixe do sexo oposto aumentou a freqüência de ondulação (corte) em machos e fêmeas, induziu desova em fêmeas e aumento do IGS em machos. A comunicação química não teve efeito sobre os parâmetros analisados. Conclui-se que a comunicação visual com o sexo oposto é o principal fator de estimulação social na reprodução na tilápia-do- Nilo
Hypothalamic-Hypophysis-Gonad is the main neural-hormonal axis regulating fish reproduction. Such axis may be affected by male-female interactions stimulating physiological responses (as hormonal releasing and gonad development) and behavioral responses (as courtship, chasing and spawning) among the interacting animals. Thus, visual and chemical communication between opposite sex may modulate fish reproduction. This study checked the effect of visual and chemical male-female interaction in the Nile tilapia. Thus, fourteen couples were studied in four different conditions of communication: 1) only visual contact; 2) only chemical contact; 3) chemical and visual contact; 4) no sensorial contact (isolated). The reproductive behavior and gonad development were analyzed and compared among the conditions. The visual communication with the opposite sex raised the frequency of undulation (a courtship movement) in males and females, induced spawning in females and risen GSI in males. The chemical communication did not affect such parameters. It was concluded that the male-female visual communication is the main social stimulation factor on Nile tilapia reproduction

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Castro, André Luis da Silva. "Efeito de estímulos visuais e químicos do sexo oposto na reprodução da tilápia-do-Nilo /." Jaboticabal, 2004. http://hdl.handle.net/11449/144153.

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Orientador: Gilson Luiz Volpato
Banca: Eliane Gonçalves de freitas
Banca: Rosana Mattioli
Resumo: A reprodução dos peixes é regulada pelo eixo hipotálamo-hipófise-gônadas. As interações entre machos e fêmeas podem afetar esse eixo, desencadeando respostas fisiológicas, como a secreção de hormônios reprodutivos e o desenvolvimento das gônadas, e comportamentais, como corte, perseguição, desova e espermiação nos membros participantes. Dessa forma, a comunicação visual e química com um peixe do sexo oposto pode modular a reprodução. O objetivo deste trabalho foi testar o efeito da comunicação visual e química com o sexo oposto na reprodução da tilápia-do-Nilo. Para isso, quatorze casais de tilápia-do-Nilo foram mantidos em cada uma das seguintes condições, que variaram apenas quanto ao tipo de comunicação permitida entre o casal: 1) comunicação visual; 2) comunicação química; 3) comunicação química e visual; 4) isolados (sem qualquer contato entre o casal). O comportamento reprodutivo e o desenvolvimento das gônadas dos machos e fêmeas foram analisados e comparados entre as condições. A comunicação visual com o peixe do sexo oposto aumentou a freqüência de ondulação (corte) em machos e fêmeas, induziu desova em fêmeas e aumento do IGS em machos. A comunicação química não teve efeito sobre os parâmetros analisados. Conclui-se que a comunicação visual com o sexo oposto é o principal fator de estimulação social na reprodução na tilápia-do- Nilo
Abstract: Hypothalamic-Hypophysis-Gonad is the main neural-hormonal axis regulating fish reproduction. Such axis may be affected by male-female interactions stimulating physiological responses (as hormonal releasing and gonad development) and behavioral responses (as courtship, chasing and spawning) among the interacting animals. Thus, visual and chemical communication between opposite sex may modulate fish reproduction. This study checked the effect of visual and chemical male-female interaction in the Nile tilapia. Thus, fourteen couples were studied in four different conditions of communication: 1) only visual contact; 2) only chemical contact; 3) chemical and visual contact; 4) no sensorial contact (isolated). The reproductive behavior and gonad development were analyzed and compared among the conditions. The visual communication with the opposite sex raised the frequency of undulation (a courtship movement) in males and females, induced spawning in females and risen GSI in males. The chemical communication did not affect such parameters. It was concluded that the male-female visual communication is the main social stimulation factor on Nile tilapia reproduction
Mestre

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Teixeira, Juliana Maria Freitas. "Comportamento e bem estar de leitões desmamados aos 28 dias agrupados por sexo e provenientes de diferentes tipos de maternidades." Universidade Federal de Viçosa, 2009. http://locus.ufv.br/handle/123456789/5643.

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Aiming at itself to evaluate the behavior and the welfare of pigs, in function of the grouping for sex and type of maternity had been used 180 pigs weaned to the 28 days distributed in an experiment with delineation entirely casualizado in factorial project 3x3 (three groupings for sex: males, females and compound with three types of maternity origin: conventional maternity, maternity with floor with cooling for matrices and maternity with access the poles), five repetitions of four animals for experimental unit. The comments had been carried through in the day wean of it and in days 2 and 3 it weans after it. The analyses of the images had been carried through by an only person. Significant differences (P≥ 0,05) for the isolated factors had not been observed and nor effect of the interaction enter the factors how much to the performance of the pigs. Significant effect (P≥0,05) of the interaction of the type of maternity with sex how much to the number of times had been observed where the animal used the water through, where the animal mounted the friend of bay and where the animal practised biting. For the behaviors, playful permanence in cocho, behaviors and agonísticos behaviors had verified effect of the factors of isolated form (P≥0,05). It was verified that the effect of the factor type of maternity and the interaction of the factors had been significant (P≥0,05) how much to the time where the pigs had remained lying. One concludes that the grouping for sex enriches the welfare conditions of the pigs, weaned to the 28 days, in the day-care center; that the grouping exclusively of males harms the behavior of pigs weaned to the 28 days of age and that the maternity with access the pole improves the behavior of the pigs in the day-care center weans after it to the 28 days of age, presenting resulted better of welfare that of the maternity with cooling for the nuts.
Visando-se avaliar o comportamento e o bem estar de leitões, em função do agrupamento por sexo e tipo de maternidade foram usados 180 leitões desmamados aos 28 dias distribuídos em um experimento com delineamento inteiramente casualizado em esquema fatorial 3x3 (três agrupamentos por sexo: machos, fêmeas e misto com três tipos de origem de maternidade: maternidade convencional, maternidade com piso com resfriamento para matrizes e maternidade com acesso a piquetes), com cinco repetições de quatro animais por unidade experimental. As observações foram realizadas no dia do desmame e nos dias 2 e 3 após o desmame. As análises das imagens foram realizadas por uma única pessoa. Não foram observadas diferenças significativas (P≥0,05) para os fatores isolados e nem efeitos da interação entre os fatores quanto ao desempenho dos leitões. Foram observados efeitos significativos (P≥0,05) da interação do tipo de maternidade com sexo quanto ao número de vezes em que o animal utilizou o bebedouro, em que o animal montou o companheiro de baia e em que o animal praticou biting. Para os comportamentos, permanência no cocho, comportamentos lúdicos e comportamentos agonísticos verificaram-se efeitos dos fatores de forma isolada (P≥0,05). Verificou-se que os efeitos do fator tipo de maternidade e a interação dos fatores foram significativos (P≥0,05) quanto ao tempo em que os leitões permaneceram deitados. Conclui-se que o agrupamento por sexo enriquece as condições de bem estar dos leitões, desmamados aos 28 dias, na creche; que o agrupamento exclusivamente de machos prejudica o comportamento de leitões desmamados aos 28 dias de idade e que a maternidade com acesso a piquete melhora o comportamento dos leitões na creche após o desmame aos 28 dias de idade, apresentando resultados melhores de bem estar que os da maternidade com resfriamento para as porcas.

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Paitio, José Rui Lima. "Vision and behaviour in deep-sea fishes : distribution of neural retinal cells in Myctophidae i." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14040.

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Mestrado em Biologia Marinha
This work aims to analyse the density and distribution of neuron cells on retinae of myctophid fishes in relation to ecological and behavioural parameters. Retinal wholemounting technique allowed the observation of topographic densities for photoreceptors (PRs), retinal ganglion cells (RGCs) and amacrine cells (ACs) in adult myctophids. These data allowed the identification of retinal specializations and the estimation of visual acuity and sensitivity, and sensitivity to bioluminescence flashes and to downwelling light. The seven analysed myctophid species showed high density of PRs and low density for RGCs. Different retinal specializations reflect behavioural differences between myctophid species. Visual parameters are influenced mainly by ecological factors, but phylogenetic relationships are also a factor that may explain the distribution of retinal cells in myctophids. In conclusion, all species in this study showed high visual sensitivity and low acuity, suggesting a great adaptation to mesopelagic light conditions.
O objectivo deste trabalho centrou-se na análise das distribuições de densidade em células neuronais de retinas de mictofídeos e na relação com parâmetros ecológicos e comportamentais. Retinal wholemounting technique permitiu a determinação de densidades topográficas de fotoreceptores (PRs), células ganglionares da retina (RGCs) e células amácrinas (ACs) em mictofídeos adultos. Estes dados possibilitam a identificação de especializações retinais e desenvolver estimativas de acuidade e sensibilidade visual, assim como sensibilidade à luz de origem bioluminescente ou solar. As sete espécies de mictofídeos analisadas apresentam elevada densidade de PRs e baixas densidades de RGCs. Especializações retinais divergentes reflectem diferenças comportamentais entre espécies de mictofídeos. Os parâmetros visuais são influenciados essencialmente por factores ecológicos, mas as relações filogenéticas são também um factor que poderá explicar os padrões de distribuição de células retinais em mictofídeos. Concluindo, as espécies estudadas revelam elevada sensibilidade visual e baixa acuidade, sugerindo uma grande adaptação às condições de luminosidade da zona mesopelágica.

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Middlebrooks, Michael Louis. "Consequences of Kleptoplasty on the Distribution, Ecology, and Behavior of the Sacoglossan Sea Slug, Elysia clarki." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4162.

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The sacoglossan sea slug Elysia clarki is able to photosynthesize for three to four months using chloroplasts sequestered from its algal food sources. Furthermore, the slug is able to store multiple chloroplasts from different algal species within the same cell. This research, consisting of several related studies, explores the role that provision of organic nutrients via photosynthesis plays in the biology of the slug. The first chapter demonstrates that, under conditions of starvation, photosynthetic activity in E. clarki remains fully functional for one month after which it then declines. During the first month of starvation the slug exhibits similar feeding behavior as slugs provided a continuous supply of food, suggesting that photosynthesis delays the onset of starvation-induced behavioral changes. The second chapter explores E. clarki's spatial relationships with algae known to be food sources in the field. In areas with high slug density, edible algal populations were very low. DNA barcoding was employed to demonstrate that the algae found near slugs were poor predictors of which foods were actually consumed by slugs. Generally, there was a mismatch between algae available in the field and slug diets. The third chapter explores how E. clarki is able to maintain photosynthesis. After labeling with a C14 ALA incubation process, then chlorophyll was extracted from slugs and purified using HPLC. Results indicate that recently collected E. clarki are able to synthesize chlorophyll, whereas slugs starved for 3 months were not. Photosynthesis plays a very important role for E. clarki and its relationships with food algae.

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Thorlacius, Magnus. "Round goby invasion of the Baltic Sea : the role of phenotypic variation." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-111910.

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Biological invasions are a major threat to biodiversity world wide with annual economic costs up to 1.4 trillion dollars. The round goby (Neogobius melanostomus) is a particularly fierce invader that threatens ecological function of the Baltic Sea. Individual variation in behavioral traits that remain constant through time and context have been identified as crucial factors for explaining different parts of the invasion process. For example, asocial behavior facilitates dispersal from high density populations and comes with fitness benefits in low conspecific density. The latter is especially relevant, in an invasion context, following the initial colonization of a novel environment when population density usually is low. This thesis investigates the role of individual variation in phenotypic traits on species invasions. The main focus is on the effects of sociability, activity and boldness, but also including aggression and physiological stress tolerance, on dispersal tendency and selection at invasion fronts. To do this, we studied four round goby populations in the Baltic Sea, two of the most recently established and two of the oldest populations. In 2012 we demonstrated that asocial, active and bold round gobies are overrepresented at invasion fronts. Two years later we showed that dispersal from the new populations was led by individuals with high activity levels, while in all populations larger individuals dispersed. We also determined the length of the socalled lag-phase, between colonization and spread, in both newly established populations. The end of the lag-phase is hypothesized being triggered by high population density in the harbors leading to dispersal and subsequen colonization of the surrounding areas by small asocial individuals. In our final experiment, we present evidence of stress coping styles in round gobies, in which more aggressive individuals are also more stress tolerant and vice versa. Though we found no connection between stress coping and population age, we found that mortality was unaffected by population density and that the gobies became more aggressive and stress tolerant when kept in high density. To conclude, we have shown that: 1) individuals with high levels of activity, boldness and asociality are common at invasion fronts; 2) a lag phase occurs between colonization and spread in round goby invasions; 3) asocial individuals drive the spread from high density populations at the invasion front and; 4) round gobies adapt to high densities with high aggression and stress tolerance.

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Robinson, Rusty Wade. "Post-Den Emergence Behavior and Den Detection of Polar Bears (Ursus maritimus) in Northern Alaska and the Southern Beaufort Sea." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4403.

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Pregnant polar bears (Ursus maritimus) construct maternal dens out of snow in the autumn where they give birth to and raise altricial young. In recent years, there has been a decrease in polar sea ice extent and thickness, which has led to changes in denning behavior. One such change in the southern Beaufort Sea (SBS) is that polar bears are selecting maternal den sites on land, rather than on unstable sea ice. This change, coupled with expanding petroleum exploration along Alaska's North Slope, heightens the likelihood of bear-human interactions at maternal den sites. The purpose of this research was to 1) describe polar bears' post-den emergence behavior, establishing a benchmark for comparison to identify behavioral changes associated with climate change and disturbance, and 2) explore factors influencing the efficacy of a currently used den detection method, forward-looking infrared (FLIR). Maternal den sites were observed along Alaska's North Slope from March to April of 2009 and 2010. The mean length of stay at den sites post-emergence was 11.3 ± 7.5 d. The mean date of den emergence was 14 March; abandonment 26 March. Adult females were generally inactive (58.4% out-of-den time) with standing being the most prevalent activity (49.9%). Cubs were generally active (76.7%), playing more than any other activity (45.3%). Bears spent the majority of their time in the den (97.3% for adult females and 99% for cubs) with short bouts of intermittent activity (× = 7 min 42 s). We documented the death of one member of a triplet polar bear litter at its den site. All three cubs showed low activity levels relative to other cubs observed, and one died within one week of den emergence. Necropsy confirmed that the dead cub had a low body weight and was malnourished. Capture later confirmed that the two surviving cubs were also undersized. Triplet litters are often smaller and suffer higher mortality rates than singletons and twins. This cub was not only a triplet but also born following 2 y of record minimum sea ice extent, both of which may have played a role in this cub's death. Concurrent with the den emergence portion of this work, we conducted a separate study to identify limitations and optimal conditions for locating dens using FLIR. We took handheld FLIR images of three artificial dens under varied conditions. We tested variables hypothesized to influence detectability with linear models using a zero-inflated negative binomial distribution. Solar radiation, wind speed, and den wall thickness reduced the likelihood of detecting dens. The negative effect of wind speed on detectability increased with increasing distance. To maximize the efficacy of hand-held FLIR, den surveys should be conducted when solar radiation is <16 w/m2 (night) and when wind speed is <10 km/h (6 mph). Adherence to these guidelines will maximize the protection FLIR can afford to denning bears.

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Vantorre, Thomas. "Communication chimique et compétition lors de la reproduction chez Gastrophysa viridula, Coleoptera: Chrysomelidae." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209328.

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Parmi les modes de communication les plus exploités chez les insectes, la communication chimique figure en bonne place. D’ailleurs, la recherche moderne consacrée aux signaux chimiques émis et perçus par les individus d’une même espèce n’a de cesse de se développer depuis plus de 50 ans. A travers ce travail de thèse, nous nous sommes intéressés à ces phéromones associées au comportement sexuel de Gastrophysa viridula (Coleoptera :Chrysomelidae). Nous avons menés, dans ce cadre, plusieurs bioessais comportementaux liés pour la plupart à des analyses chimiques par chromatographie gazeuse couplée à une spectrométrie de masse (GC-MS).

La fonction la plus évidente de la phéromone sexuelle de G. viridula est l’induction du comportement sexuel mâle. Cet « aphrodisiaque », probablement constitué de plusieurs composés cuticulaires (des alcanes méthylés lourds), est émis par la femelle et déclenche par contact la sortie de l’édéage des mâles. Etonnamment, ces composés se retrouvent aussi chez les mâles de G. viridula dont le comportement sexuel est alors induit au contact de composés cuticulaires mâles. Ceci constituerait la cause proximale des comportements homosexuels observés chez les mâles de G. viridula. Nous avons ensuite étudié le rôle des composés cuticulaires dans l’isolement sexuel entre G. viridula et G. cyanea. Le comportement sexuel des mâles des deux espèces est en effet induit préférentiellement par les femelles conspécifiques. Pour G. viridula, cette préférence est visiblement attribuable aux composés cuticulaires. Enfin, les signaux chimiques sont parfois indicateurs du degré de compétition spermatique rencontré par un mâle et permettent à celui-ci d’ajuster la quantité de spermatozoïdes transmis à une femelle. Avant d’étudier l’implication de tels signaux chez G. viridula, nous avons souhaité mettre en évidence un ajustement de la quantité de spermatozoïdes transmis par des mâles soumis à divers degrés de compétition spermatique. Nos résultats ne nous permettent malheureusement pas de signaler un tel effet.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Costanzo, Marna S. "Aspects of memory in the Damaraland mole-rat, Cryptomys damarensis spatial learning and kin recognition /." Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-07032007-130259.

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Andrade, Ederson Américo de. "Consumo de forragem, desempenho animal e emissão de metano entérico por bovinos em pastos de capim-elefante anão com ou sem acesso a amendoim forrageiro." Universidade do Estado de Santa Catarina, 2013. http://tede.udesc.br/handle/handle/898.

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Made available in DSpace on 2016-12-08T16:24:16Z (GMT). No. of bitstreams: 1 PGCA13MA108.pdf: 977023 bytes, checksum: fe38f03043d055013017d24a7b4a3124 (MD5) Previous issue date: 2013-08-02
Management strategies for increasing legumes I the ruminant diets and mitigate methane emissions on tropical livestock production systems need to b better studied. The aim of this work was to evaluate herbage intake, animal performance and enteric methane of cattle grazing dwarf elephant grass (Pennisetum purpureum cv BRS Kurumi) pastures with or whithout access to an exclusive area of peanuts (Arachis pintoi cv Amarillo) pastures. The experimental treatments were: dwarf elephant grass (DEG) pastures in extreme cultivation receiving nitrogen fertilization (150 kg N/ha as ammonium nitrate) and DEG intercropped with peanuts (Arachis pintoi cv Amarillo) plus an adjacent area formed by the same legume which was allowed to be accessed by grazing animals for 5 h/day (from 7 to 12 am). Twelve Charolais steers (213 +- 8.9 kg of body live weight, LW) were assigned in four groups, two per treatment. The animals were managed according to a intermittent grazing method with an herbage allowance of dry leaf of 6.0 kg/100 kg of LW. Both, average daily gain and DM herbage intake were higher (P<0.05) while morning and total grazing time were lower (P<0.001) for animals grazing legume pastures. The daily methane emissions was higher (P<0.05) in animals grazing legume pastures, whereas methane emission by kg of DM intake was not affected by treatments. Steers grazing DEG with access to peanut pastures can improve their performance without increased methane production by kg of DM intake
O uso eficiente das leguminosas tropicais na produção de ruminantes a pasto pode ser uma alternativa para melhoria dos índices zootécnicos, agronômicos e ambientais. O objetivo deste trabalho foi avaliar o consumo de forragem, o desempenho animal e a emissão de metano entérico por bovinos pastejando capim-elefante anão (Pennisetum purpureum cv. BRS Kurumi) com ou sem acesso a uma área exclusiva de amendoim forrageiro (Arachis pintoi cv amarillo). Os tratamentos experimentais foram: pasto de capim elefante anão em cultivo estreme (CEA) recebendo adubação nitrogenada (150 kg/há de N na forma de nitrato de amônio) e capim elefante anão consorciado com amendoim forrageiro (Arachis pintoi cv Amarillo), mais uma área adjacente formado pela mesma leguminosa com acesso dos animais no pasto por 5 h/dia (7-12 horas) (CEL). Doze bovinos Charolês (213 + - 8,9 kg de peso vivo, PV) foram distribuídos em quatro grupos, dois por tratamento. Os animais permaneciam em pastejo intermitente, com uma oferta de MS de folhas verdes de 6,0 kg/100 kg de PV. O ganho médio diário (P<0,01) e consumo de MS (P < 0,05) foram maiores, enquanto o tempo de pastejo pela manhã e tempo total de pastejo foram menores (P < 0,001) nos animais que tiveram acesso à leguminosa. A emissão diária de metano foi superior (P < 0,05) nos animais com acesso à leguminosa, enquanto a emissão de metano por kg de MS consumida não foi afetada pelos tratamentos. Bovinos pastejando capim-elefante anão com acesso horário a amendoim forrageiro melhoram seu desempenho e a eficiência do tempo alocado para atividade de pastejo sem aumentar a produção de metano por kg de MS ingerida

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Juškevičiūtė, Justina. "Informacijos perdavimo lytiniais feromonais tyrimas Canis familiaris pavyzdžiu." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070816_165108-88602.

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Dabar vis daugiau mokslininkų bando identifikuotus gyvūnų feromonus sintetinti ir panaudoti praktinėms reikmėms, pavyzdžiui, vabzdžių sintetinių feromonų analogus naudoti kovai su žemės ūkio kenkėjais. Tačiau tik XX amžiaus pabaigoje pradėta domėtis ir žinduolių feromonais. Viena iš naujų tiriamų sričių yra: lytinių feromonų įtaka gyvūnų lytinei elgsenai. Lytinė elgsena yra vienas iš svarbiausių šunų kaip ir, bet kurios kitos gyvosios sistemos egzistavimo garantas, todėl tai paskatino mus išsamiau paanalizuoti šunų lytinės elgsenos modelį (asistavimą). Taip pat mūsų tikslas buvo sumodeliuoti tokį biotestavimo modelį kaip materiali informacija paveikia individo (šuns) elgesį ir nustatyti bei apibūdinti kas tai yra ta informacija, šiuo atveju – cheminė medžiaga. Tyrimai buvo atlikti 2005 – 2007 metais. Buvo surinkti šlapimo ėminiai iš skirtingų šunų veislių devynių kalių nerujos ir rujos metu. Ėminių rinkimo metodika buvo specialiai sukurta įgyvendinti mūsų užduotis ir yra originali. Viena dalis rinkimo metu surinktos medžiagos buvo išsiusta į Karališkąjį Technologijų Institutą Stokholme (Royal Institute of Technologies). Atlikus pirminius ėminių tyrimus, nustatyta jog tik rujojančių kalių šlapime yra TC medžiaga. Antra dalis rinkimo metu surinktos medžiagos buvo naudota biotestui. Po to buvo atlikti du biotestavimai lauko sąlygomis Pietų Rusijos aviganių veislyne „Balandis“. Šiuose tyrimuose buvo atlikti testavimai su šios veislės patinais pagal 7 mūsų sukurtus testavimo... [toliau žr. visą tekstą]
More and more scientists nowadays are trying to syntetic animals‘ pheromones and use them for practical purposes. Analogues of syntetic pheromones, for instance, are used in agriculture against pests. It was only in the end of the 20th century, however, that mammals‘ pheromones, too, started arousing interest. One of the new fields of resaerch is the animals‘ sexual behaviour. Sexual behaviour is one of the guarantees of dogs‘, as well as any other living systems‘ existence. Then an idea suggested itself to us to analyze more deeply the model of this type of behaviour amoung dogs. Our aim was also to set up a model of biotesting in what way material information is reflected on an individual‘s (dog‘s) behaviour and to establish what that information is. In this case – a chemical substance. The research was carried out between 2005 and 2007. Urine samples were gathered from bitches of different dogs‘ breeds then they were on the heat and when they were not on the heat. The method of taking the samples was specially created to satisfy our requirements and is original. One part of the samples gathered was sent to the Royal Institute of Technologies in Stockholm. The research conducted on the primary samples showed that the substance TC was to be found only in the urinie of bitches (females) that were on the heat. The rest of material gathered was used for examination. Then two biotests (in outside)was conducted at the South Russian Sheep – dog kennel “Balandis“. Researched... [to full text]

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Brelin, Daniel. "Stress Coping Strategies in Brown Trout (Salmo Trutta): Ecological Significance and Effects of Sea-Ranching." Doctoral thesis, Uppsala universitet, Jämförande fysiologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8591.

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Two distinct stress coping strategies, proactive and reactive, have been stated in various animal studies, each associated with a set of behavioural and physiological characteristics. In a given challenging situation, proactive animals show more aggression, a higher general activity and a predominant sympathetic reaction. In contrast, the reactive copers respond more with immobility and avoidance, and a predominant parasympathetic/hypothalamic activation. This divergence in coping has also been indicated in salmonid fish. Interestingly, many of the differences reported between sea-ranched and wild fish resembles characteristics that differentiate proactive and reactive copers. In the present thesis it is shown that individuals with divergent stress coping styles are identifiable in several brown trout (Salmo trutta) populations. Further, the results show that the distribution of individuals displaying these distinct stress coping strategies differs between populations. This strongly indicates that these traits are heritable and that the variation in selection regime in the native rivers influences these traits. In addition, the results show that populations with hatchery origin are biased towards having higher frequencies of trout displaying a proactive style than populations having wild origin. Also, even though the frequency of early sexual maturation, known as a viable alternative life history in salmonids, differs between populations of brown trout, no link between stress coping strategy and early sexual maturation were found. However, this thesis show that maternal contribution, in the form of egg size, is of major importance whether the progeny will sexually mature early and that it also might be of importance for stress coping strategy. Further, correlations of traits commonly associated with stress coping strategies and behavioural syndromes across context and over time is investigated. The results show that individuals with a strong sympathetic reactivity are more prone to change their behaviour than others.

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MOURA, Roseana Tereza Diniz de. "Perfil comportamental do gato doméstico (Felis silvestris catus, Linnaeus, 1758) sem raça definida criado em abrigo : estudo da relação do temperamento com a cor da pelagem." Universidade Federal Rural de Pernambuco, 2008. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5840.

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Cats have always had an important part to play in human civilization ¾ they were religious, power and magic symbols, and saved humanity from pests. Its adaptability, independence and versatility have placed the cat as the most popular pet in actuality. The study of individuality in animals has raised interest for several reasons ¾ the animal’s well being, the application of its behavioral traits for the benefit of humans, the prediction of behavioral problems in the future, its reproductive success and as a model for the study of the evolution of personality in humans, among others. In aiming to contribute to the welfare of mixed breed domestic cats that live in shelters ¾ by enhancing adoption, reducing abandonment, and minimizing stressful factors and consequent illness ¾, this research work had as its objective to study the relation of coat colour and temperament in mixed breed domestic cats defining its “Temperamental Profile”; as well as to define the “Behavioral Profile” of sheltered mixed breed domestic cats in the context of social relationships with familiar and unfamiliar cats and humans. For this purpose were used, in the Metropolitan Region of Recife, Pernambuco State, 263 cats from 24 shelters, healthy males and females of differing weight, aged 12 months and over, and with coat colour dense black solid (100), bi-colour black and white (130) and dense white solid (33). The temperamental profile of cats regarding the colour of their coat identified the dense black solid colour type of cat as adaptable (96.0%) and obedient (57.1%); the bi-colour blackand white as possessive (11.9%) and more inactive (18.5%) and the dense white as solitaire (56.3%), peacefulless (12.1%), hard adaptable (24.2%) and non possessive (93.1%), when compared among them. The behavioral profile of sheltered cats in social relations with familiar (fp) and unfamiliar (up) humans showed animals that are socials (81.75% fp and 72.62% up), curious (81.15% fp and 81.54% up), that like gaining attention (81.75% fp and 69.20% up) and rubbing themselves against people (81,0%), playful (60.84% fp and 56.87% up), talkative (53.61% fp and 62.85% up), seldom aggressive (97.72% fp and 96.54% up) and secure (85.17% fp and 69.58% up); and in its social relations with familiar (fc) and unfamiliar (uc) cats referred to animals that are socials (92.78% fc and 80.92% uc), curious (84.23% fc and 83.85% uc), that appreciate lying together with other cats (80.61%) and being caressed by them (82.76%), playful (53.99% fc and 42.0% uc), “talkative” (69.11% fc and 72.76% uc), non aggressive 95.44% fc and 88.58% uc) and secure (93.54% fc and 87.64% uc). The results allowed to conclude that the coat colour is related to the temperamental profile of mixed breed domestic cats, with dense black solid coat colour animals more adaptable and obedient, thebi-colour black and white as less active and more possessive, while the dense white solid cats as animals that appreciate being alone, are less peaceful and adaptable and much less possessive, when compared among them; however do not significantly interfere in the social relation of the cat with people and other cats. The behavioural profile of sheltered cats in the social relation with familiar and unfamiliar people refers to animals that are very social, docile and curious, that very much appreciate being caressed, rubbing on people and gaining their attention, like being held on lap and arms, playful, talkative, andseldom insecure; being influenced by the number of people which they keep contact. The behavioural profile of sheltered cats in the social relation with familiar and unfamiliar cats refers to animals that are very social, tame, curious and self-confident, that very much appreciate lying together and being caressed by other cats, playful and little talkative; being influenced by the local where the animals are kept and the number of people which they keep contact.
Os gatos sempre desempenharam papel importante na história da civilização humana ¾ já foram símbolo religioso, de poder e de magia, e livraram a humanidade de pragas. Sua adaptabilidade, independência e versatilidade têm situado o gato doméstico (Felis silvestris catus) como animal de estimação mais popular, na atualidade. O estudo da individualidade em animais tem despertado interesse por muitas razões ¾ promover seu bem-estar, procriá-los com sucesso, prever distúrbios comportamentais futuros destes, aplicar seus atributos comportamentais para benefício do ser humano; usá-los como modelo de estudo da evolução da personalidade em humanos, entre outras. Buscando contribuir com o bem-estar de gatos domésticos sem raça definida criados em abrigos ¾ incentivar adoções, reduzir abandono, evitar fatores estressantes e consequentes doenças ¾, este trabalho teve como objetivo estudar a relação da cor da pelagem com o temperamento do gato doméstico sem raça definida a partir do “Perfil Temperamental” deste; assim como definir o “Perfil Comportamental” do gato doméstico sem raça definida criado em abrigo na relação social com outros gatos e com seres humanos, conhecidos edesconhecidos. Na Região Metropolitana do Recife, estado de Pernambuco, foram selecionados 263 gatos de 24 abrigos, machos e fêmeas saudáveis com peso variado e idade a partir de 12 meses, e de pelagens nas cores preta sólida (100), bicolor preta e branca (130) e branca sólida (33). O perfil temperamental do gato doméstico sem raça definida segundo a cor da pelagem definiu os animais de pelagem preta sólida como adaptáveis (96,0%) e obedientes (57,1%); gatos de pelagem bicolor preta e branca como possessivos (11,9%) e pouco ativos (18,5%) e os de pelagem branca sólida como solitários (56,3%), intranqüilos (12,1%), de difícil adaptação (24,2%) e não possessivos (93,1%), quando comparados entre si. O perfil comportamental de gatos domésticos sem raça definida criados em abrigo na relação social com pessoas conhecidas (pc) e desconhecidas (pd) identifica animais sociais (81,75% pc e 72,62% pd) e curiosos (81,15% pc e 81,54% pd), que gostam de atenção (81,75% pc e 69,20% pd) e de se esfregar (81,0%), brincalhões (60,84% pc e 56,87% pd), vocálicos (53,61% pc e 62,85% pd), não agressivos (97,72% pc e 96,54% pd) e seguros (85,17% pc e 69,58% pd); e na relação social comgatos conhecidos (gc) e desconhecidos (gd) refere-se a animais sociais (92,78% gc e 80.92% gd) e curiosos (84,23% gc e 83,85% gd), que gostam de deitar juntos (80,61%) e receber carícias (82,76%), brincalhões (53,99% gc e 42,0% gd), vocálicos (69,11% gc e72,76% gd), não agressivos (95,44% gc e 88,58% gd) e seguros (93,54% gc e 87,64% gd). Os resultados permitiram concluir que a cor da pelagem, nas cores estudadas, está associada ao perfil temperamental de gatos sem raça definida, com animais de pelagem preta sólida mais adaptáveis e obedientes, os de pelagem bicolor preta e branca menos ativos e mais possessivos, enquanto que os de pelagem branca sólida apreciam muito ficar sozinhos, são menos tranqüilos e adaptáveis, e raramente possessivos, quando comparados entre si; contudo não interfere significantemente na relação social do gato com pessoas e outros gatos. O perfil comportamental de gatos sem raça definida criados em abrigo na relação social com pessoas conhecidas e desconhecidas refere-se a animais muito sociais, dóceis e curiosos, que gostam muito de se esfregar em pessoas e da atenção destas, que aceitam colo e/ou braço, brincalhões, pouco vocais e raramente inseguros; sendo influenciado pelo número de contactantes humanos com os quais estes convivem. O perfilcomportamental de gatos sem raça definida criados em abrigo na relação social com outros gatos conhecidos e desconhecidos refere-se a animais muito sociáveis, dóceis, curiosos e autoconfiantes, que apreciam muito deitar juntos e receber carícias, brincalhões, e pouco vocais; sendo influenciado pelo local onde os animais são mantidos e o número de pessoas com os quais mantêm contato.

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Gaujac, Danielle Pereira. "Influência do hipotireoidismo gestacional experimental no comportamento ingestivo e perfil metabólico da prole de ratas." Pós-Graduação em Ciências Fisiológicas, 2013. https://ri.ufs.br/handle/riufs/3965.

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Recent experimental approaches attribute value to events occurring during intrauterine life as crucial in the onset of several diseases during postnatal life. Thyroid hormones (TH) are critical to the physiology of metabolism and body development. The aim of this study was to investigate the repercussions of lack of TH during pregnancy on body mass gain, metabolic profile, ingestive behavior of food, sodium (0.3M NaCl) and water in rat offspring at different postnatal ages. The experimental gestational hypothyroidism (EGH) was induced by the administration of 0.02% methimazole (MMI) in ad libitum drinking water from day 9 of gestation until delivery. Offspring (males and females) from MMI-treated dams (OMTD) were compared to their corresponding control offspring (i.e. male and female offspring from water-treated dams; OWTD). Insulin tolerance test (ITT) and glucose tolerance test (GTT) were also performed. Two- or three-way ANOVA followed by Bonferroni post-test were performed when necessary. OMTD showed lower body weight on PND 23 and 30 (p<0.0001). Similar profile was observed when the offspring were separated by gender, at least during the experimental period (PND 60, 90 and 120; p<0.0001 for both genders). However, there was no difference in the amount of food intake when males of OMTD (m-OMTD) were compared to OWTD (m-OWTD). Female of OMTD (f-OMTD) had lower ability to reduce glucose plasma level at ITT (p = 0.0224), otherwise, no change in GTT (p = 0.1313) was observed. At PND 60, glucose plasma level was higher in f-OMTD than in f-OWTD (p = 0.013). In m-OMTD, plasma cholesterol was higher in PND 60 and lower on PND 120 (p <0.0001), when compared to m-OWTD. In f-OMTD, cholesterol was lower only at PND 120 (p = 0.035). The high density lipoprotein (HDL) cholesterol was lower in OMTD on PND 15 and 30 (p = 0.04) and remained lower only in f-OMTD on PND 120 (p = 0.024). Moreover, EGH induced an increased in plasma triglycerides (TGL), as well as, in serum level of very low density lipoprotein (VLDL) cholesterol in offspring at DPN 15 (p = 0.039) and also after puberty (at DPN 60), but only the m-OMTD (p < 0.0001). The serum urea was lower in OMTD on PND 15 and 30. Interestingly, serum urea was inverted at DPN 60 in both, m- and f-OMTD (p = 0.006, and p = 0.003, respectively), when compared to their respective control groups. At PND 120, retroperitoneal fat weight was lower both in m- (p = 0.05) and f-OMTD (p = 0.009). Additionally, at all studied ages, relative kidney and liver mass was lower in m- (p = 0.001) and f-OMTD (p = 0.008). In conclusion, we demonstrated, for the first time, that maternal TH are critical to the ontogenetic development of systems that regulate energy metabolism throughout the life of the offspring, resulting in a reduction in body mass, biochemical instability throughout the life, lower sensitivity to insulin in females, and, a delay in the development of critical organs for the metabolism of macronutrients.
Recentes abordagens experimentais têm imputado valor aos eventos ocorridos durante a vida intrauterina como cruciais no aparecimento de doenças na vida pós-natal. Os hormônios tireoidianos (HTs) são críticos para fisiologia do metabolismo e desenvolvimento corporal. O objetivo do presente estudo foi investigar as repercussões da carência dos HTs em ratas prenhes na evolução ponderal da massa corporal, perfil bioquímico, comportamento ingestivo de ração, água e sódio (NaCl 0,3M) da prole em diferentes idades pós-natais. O hipotireoidismo gestacional experimental (HGE) foi induzido através da adicão de metimazol 0,02% na água de beber a partir do dia 9 de gestação até o parto. O grupo de prole (machos e fêmeas) de mães hipotireoideanas (PMH) foi comparado ao grupo controle de mães eutireoideanas (PME). Realizou-se o teste de tolerância à insulina (TTI) e o teste de tolerância à glicose (TTG). Os dados foram submetidos ao teste de ANOVA de duas ou três vias, quando necessário, seguidos do pós-teste de Bonferroni. De acordo com os resultados obtidos, observou-se que a PMH apresentou massa corporal menor aos 23 e 30 dias pós-natal (DPN) (p<0,0001). Padrão similar foi encontrado quando as proles foram separadas por gênero, aos 60, 90 e 120 DPN (p<0,0001, para ambos os gêneros). No entanto, não houve diferença significativa na ingestão de ração entre os machos PMH e PME. As fêmeas da prole de mães hipotireoideanas (f-PMH) apresentaram menor capacidade de reduzir a glicemia no TTI (p=0,0224) sem alteração no TTG. Aos 60 DPN, a concentração sérica de glicose foi maior nas f-PMH (p = 0,013) que nas f-PME. Nos machos prole de mães hipotireoideanas (m-PMH) o colesterol plasmático foi elevado aos 60 DPN e reduziu aos 120 DPN (p<0,0001), quando comparado aos machos prole de mães eutireoideanas (m-PME). Nas f-PMH o colesterol sérico foi menor somente aos 120 DPN (p=0,035). O HDL sérico foi menor na PMH aos 15 e 30 DPN (p=0,04), e continuou menor nas f-PMH aos 60, 90 e 120 DPN (p=0,024). Entretanto, o HGE elevou as concentrações séricas de TGL, bem como de VLDL, na PMH aos 15 DPN, e após a puberdade (aos 60 DPN), somente nos m-PMH (p<0,0001). A concentração sérica de ureia foi menor na PMH aos 15 e 30 DPN. Interessantemente, a ureia sérica foi invertida aos 60 DPN, se apresentando elevada tanto em m- (p=0,006) como em f-PMH (p=0,003), quando comparados aos respectivos grupos controle. Aos 120 DPN, a massa da gordura retroperitoneal foi menor tanto em m- (p=0,05) como em f-PMH (p=0,009). Adicionalmente, em todas idades estudadas, as massas relativas dos rins e do fígado foram menores tanto em m- (p=0,001) como em f- da PMH (p=0,008). Em conclusão, demonstrou-se, pela primeira vez, que os HTs maternos são críticos para o desenvolvimento ontogênico de sistemas que regulam o metabolismo de energia ao longo da vida da prole, resultando numa redução da massa corporal, instabilidade bioquímica ao longo da vida, menor sensibilidade à insulina em fêmeas, e um atraso no desenvolvimento de órgãos críticos para o metabolismo de macronutrientes.

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Palmeira, Claudia Carneiro de Araujo. "Influência da idade, sexo e dos hormônios gonadais na percepção dolorosa em modelo de dor neuropática em ratos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5152/tde-12012015-151055/.

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Os fatores idade e sexo modificam a experiência dolorosa em animais e seres humanos. Os efeitos dos hormônios gonadais têm sido estudados em diversos modelos experimentais de dor, no entanto, o efeito do envelhecimento na percepção à dor carece de mais investigação. O efeito do envelhecimento na dor neuropática ainda não está bem estabelecido. Neste estudo se procurou avaliar possíveis variações na percepção da dor da hiperalgesia mecânica, em função da idade, presença e ausência de hormônios gonadais e sexo em ratos Wistar machos e fêmeas, jovens e idosos no modelo de dor neuropática, ligadura da quinta raiz lombar. Os animais foram divididos nos seguintes grupos: ratos jovens orquiectomizados e não-orquiectomizados, ratos idosos orquiectomizados e não-orquiectomizados, ratas jovens ooforectomizadas com ou sem reposição de 17beta-estradiol e ratas idosas. Foi testado o limiar de retirada da pata após estímulo mecânico antes da ligadura e no 7º, 14º, 21º e 28o dias após a ligadura. Os resultados mostraram que todos os animais apresentaram comportamento hiperalgésico após ligadura da quinta raiz lombar durante os 28 dias de observação. A hiperalgesia ocorreu independentemente do sexo do animal, da presença ou ausência de hormônios gonadais ou idade. Não houve diferença entre ratos jovens e idosos não-orquiectomizados (p = 0,420), entre ratos jovens e idosos orquiectomizados (p = 0,560). Entre os ratos idosos com e sem orquiectomia houve diferença no 14º (p = 0,038) e 28º (p = 0,002) dias. Ratas jovens ooforectomizadas sem reposição de 17beta-estradiol apresentaram menor hiperalgesia que ratas ooforectomizadas com reposição durante todo o período (p = 0,001). Não houve diferença entre ratos idosos orquiectomizados e ratas idosas (p = 0,09). Ratos jovens não-orquiectomizados apresentaram menor hiperalgesia mecânica que ratas jovens ooforectomizadas com reposição de 17beta-estradiol (p = 0,001), o mesmo não ocorreu entre machos e fêmeas jovens gonadectomizados sem reposição hormonal (p = 0,511). Ratas jovens ooforectomizadas sem reposição de 17beta-estradiol e ratas idosas mostraram diferença apenas no 7º dia (p = 0,002). Os resultados permitiram concluir que a reposição de 17beta-estradiol aumentou a hiperalgesia mecânica aos estímulos mecânicos após ligadura da quinta raiz lombar em ratas jovens ooforectomizadas, a hiperalgesia mecânica não diferiu entre os sexos em ratos jovens machos e fêmeas, a presença da gônada masculina diminuiu a hiperalgesia mecânica em ratos idosos e que houve diminuição da hiperalgesia mecânica em ratas idosas
Age and sex modify the pain experience in animals and humans. The effects of gonadal hormones have been studied in various experimental pain models, however, the effect of aging on pain perception needs further investigation. The effect of aging on neuropathic pain is not well established. In this study, we sought to determine how aging and gonadal hormones affect mechanical hyperalgesia using spinal nerve ligation as a neuropathic pain model in aged and young male and female Wistar rats. Animals were divided into seven groups: aged female, ovariectomized young females with 17beta-estradiol replacement, ovariectomized young females without 17beta-estradiol replacement, orchiectomized and non-orchiectomized aged and young males. Rats were tested for mechanical hyperalgesia in the plantar surface of the left hindpaw before nerve ligation and on days 7, 14, 21 and 28 after nerve ligation. All animals of all groups showed mechanical hyperalgesic behavior after spinal nerve ligation during entire period of 28 days. Hyperalgesia was independent of the sex of the animal, the presence or absence of gonadal hormones or age. There was no difference between non-orchiectomized aged and young males (p = 0.420), and between orchiectomized aged and young males (p = 0.560). There was difference between aged male rats with and without orchiectomy in days 14 (p = 0.038) and 28 (p = 0.002). Young ovariectomized female rats without 17beta-estradiol replacement had less hyperalgesia than young ovariectomized female rats with replacement (p = 0.001). There was no difference between aged orchiectomized male rats and old female rats (p = 0.09). Young non-orchiectomized male rats showed less mechanical hyperalgesia than young ovariectomized female rats with 17beta-estradiol replacement (p = 0.001), that did not occur between young orchiectomized males rats and young ovariectomized females rats without 17beta-estradiol replacement (p = 0.51). Young ovariectomized female rats without 17beta-estradiol replacement and old female rats showed differences only on day 7 (p = 0.002). These data suggest that estradiol presented a pronociceptive effect in young female rats in mechanical hyperalgesia in the neuropathic pain model, spinal nerve ligation, withdrawal threshold did not differ between sex, the presence of male gonadal hormones reduces mechanical hyperalgesia in old male rats and there is reduced mechanical hyperalgesia in aged female rats

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41

Houslay, Thomas M. "Causes of adaptive differences in age-dependent reproductive effort." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/20349.

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Sexually selected ornaments are among the most spectacular traits in nature. Indeed, the extreme costs associated with producing sexual traits seem to play a crucial role in their evolution by enforcing honest levels of advertisement: only males with high levels of acquired resources (or high ‘condition’, as it is known in the literature) can afford to produce extravagant signals, a phenomenon which maintains signal reliability in a constant environment. In my thesis I examine many implications of this condition-dependent model of ornament and preference evolution for variation in age-dependent allocation to sexual signals and other life history traits. In Chapter 1, I review theoretical implications of condition-dependent signalling for life history and sexual selection theory. I note that a universal cost of expenditure in sexual advertisement is metabolic in nature: metabolites used to fund ornament expression are by definition unavailable to other life history traits that compete for a limited resource pool. This universal constraint on expenditure does more than maintain honesty (as noted above), however: the reliance of sexual displays on high levels of nutrient acquisition may help maintain genetic variation in sexual signals that would otherwise be eroded by strong mate choice, and without which the selective basis for good-genes choice would disappear. Three mechanisms in particular probably help to maintain genetic variation in acquisition. 1) Because acquiring resources and converting them efficiently to useful forms depends on the high function of many biochemical pathways, condition is undoubtedly highly polygenic, which slows the erosion of genetic variation under strong directional selection by females (especially in the presence of epistatic interactions). 2) The highly polygenic nature of condition also presents a large target for mutation, which continually restores variation at the loci under selection. 3) The many loci underlying condition may also be particularly sensitive to environmental heterogeneity in time or space. By favouring the most ornate males, females acquire high performing genes for their offspring, regardless of the precise allele combinations that have conferred the ability to acquire resources. Selection on specific alleles is liable to fluctuate over time or space whenever allelic performance is strongly context-specific. I close by noting the considerable challenges in advancing research on sexual selection and life history allocation, including the fact that two key processes central to life history (acquisition and allocation) are latent variables that interact in complexways and are intrinsically difficult to measure empirically. In the remainder of my thesis I conduct a series of experiments involving decorated crickets, Gryllodes sigillatus, which are useful models for studying life history because they enable precise measurement of male reproductive effort. Male G. sigillatus face important allocation decisions owing to the highly polyandrous nature of females, and the substantial costs involved in signalling and mating. Chapter 2 examines sex differences in age-dependent reproductive effort as a function of diet and development stage. I reared outbred crickets using four combinations of diet nutritional quality, and studied the effects of these combinations on male and female reproductive effort (calling effort in males and fecundity in females) and longevity. While I expected males to be more sensitive than females to variation in diet and developmental changes in its quality, I actually observed the opposite: males in all treatments increased calling effort over time, exhibiting consistently positive covariance between calling effort and longevity across treatments. By contrast, the relationships between female reproductive effort and longevity changed dramatically across treatments, and females who lived to intermediate ages had the highest fecundity. Although my results support sex-specific selection on life history allocation over time, a compelling additional explanation for my findings relates to the strategic role of calling for achieving male fitness. In the absence of positive feedback from potential mates, perhaps male allocation to sexual advertisement is careful and only increases gradually as a function of accumulating metabolic resources and increasing risk of intrinsic mortality. Alleles underlying condition are expected to be particularly sensitive to environmental heterogeneity. While this sensitivity may help maintain additive variation in male quality (which is essential for the sustenance of adaptive good-genes mate choice, as noted in Chapter 1), too much environmental sensitivity could also underiii mine the signal value of the male trait. For example, if there are strong genotypeby- environment interactions (GEIs) for sexual advertisement, in a rapidly changing environment females risk favouring a male whose alleles are no longer best suited to current conditions. This problem is particularly pressing for animals like crickets where males exhibit a behaviourally plastic sexual display (such as calling), and so may dynamically adjust signalling effort over time. In Chapter 3, I used inbred lines of decorated crickets to quantify age and diet dependent genetic variation in male signalling. I demonstrate that while genetic correlations across diets were quite strong for morphological traits, correlations between measures of the male sexual trait rapidly approached zero as I increased the distance in time (i.e., across widely spaced ages) or diet (i.e., comparing more dissimilar dietary histories) between samples. While extrapolating from my laboratory experiments to nature is difficult, my findings nevertheless cast doubt on the value of behaviourally dynamic signals (such as cricket calls) for reliably indicating genetic quality in realistically complex environments. In Chapter 4 I used physiological assays to evaluate factors affecting metabolite storage and use over time in decorated crickets. I manipulated the acquisition ability of all males using artificial diets that varied linearly in nutrient quality, and manipulated access to female mates over the course of the second week of adult life. By sacrificing crickets at key stages before and after manipulating the diet and social environment, I was able to estimate changes in stored metabolites, and relate these changes to calling effort and longevity. During the first week of adulthood (in the absence of females), higher diet quality significantly increased calling effort and storage of lipid, glycogen, and carbohydrate (but not protein). The presence of females increased both the probability of calling and the amount of calling during the second week, whereas diet quality only improved calling effort. By the end of the second week, calling effort had decreased, even by high quality males in the presence of females, suggesting a depletion of resources. Furthermore, the loss of condition during week 2 covaried with calling effort during the previous week irrespective of diet. Males who started the second week in high condition lost more glycogen and carbohydrate than rivals; meanwhile, lipid accumulation covaried positively with calling effort during week 2. The contrasting patterns of storage and use for lipids compared to the ‘quick-release’ metabolites (glycogen and carbohydrates) affirms starkly distinct functions for the different storage components, and underlines the importance of specific physiological measures in life history research. Finally, in the general discussion, I attempt to synthesise my thesis’s contributions to the study of life history trade-offs involving behavioural sexual displays.

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42

Buñuel, Moreno Xavier. "The role of behavioural and feedback mechanisms in mediating herbivory processes in Mediterranean seagrass ecosystems." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/673886.

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The role of consumer-resource relationship is the basis of the structure and functioning of ecological communities. The traditional lens for studying such interactions have tended to omit the importance of the species behaviour, particularly in the case of plant-herbivore interactions. However, they way the herbivore exploits the plant and the way the plant responds to that pressure is crucial in determining the stability of the interaction. Thus, both herbivore and plant performances, contextualised in the environment where the interaction takes place, can act as drivers of the resilience of the system. This thesis focuses on Posidonia oceanica ecosystems and specifically on the interaction between this seagrass and its two main herbivores – the fish Sarpa salpa and the sea urchin Paracentrotus lividus –. I assess the importance of herbivore behaviour (the aggregation patterns and feeding behaviour of S. salpa and the canopy cover dependence of P. lividus) and the resilience provided feedback mechanisms (direct responses of the plant and indirect ecosystem processes) under changing conditions resulting from global change. Disentangling these components of the interaction allows us to assess its sensitivity to each of the components and to test the response and resilience of the system under different conditions. Chapter 1 shows the importance of body size of Sarpa salpa individuals in their individual feeding activity, shoaling aggregation patterns and shoal feeding strategies, as well as the potential consequences of this on the seagrass P. oceanica. On the one hand, the larger the individuals are, the more feeding activity they show. On the other hand, S. salpa individuals tend to aggregate with conspecifics of the same body size and group size is positively related to the size of the individuals in the group. In addition, feeding strategies increase in complexity with group size and tend to be focused on very specific spots within the meadow. Thus, as individuals grow, they increase their potential impact on the seagrass, both in terms of their consumption capacity and the formation of large shoals capable of concentrating their consumption in very specific areas of the meadow. This distribution of herbivory can lead to spatial heterogeneity with consequences for the functioning of the ecosystem dominated by P. oceanica. In chapter 2, a number of regulatory mechanisms arising from an episode of intense herbivory are found to provide resilience to Posidonia oceanica system once its canopy height is reduced. Four of the mechanisms evaluated function as feedback mechanisms, one of them being actively deployed by the plant (compensatory growth) while the other three (preference for an alternative resource, increased risk of predation and reduced urchin numbers due to competition for the resource and loss of cover) are triggered indirectly and their effectiveness is based on inducing changes in the behaviour of the herbivore Paracentrotus lividus. The results obtained show how P. oceanica is able to invest efforts in recovering part of the lost leaf biomass while the system itself is able to regulate herbivory pressure as long as the environmental conditions are appropriate to the occurrence of these mechanisms. The role of these mechanisms is key to avoid the potential collapse of P. oceanica meadows under the stress caused by an episode of intense herbivory. In chapter 3, the effect of global warming on the Posidonia oceanica – Sarpa salpa interaction is assessed through a combination of gradient approaches in the field and manipulative laboratory experiments. On the one hand, the results show that increasing water temperature significantly increases S. salpa growth rates during its larval stage, reducing its larval period (fewer days in the water column) and limiting its dispersal, while showing no effect on feeding behaviour during its adult phase. On the other hand, warming negatively affects the growth rates of P. oceanica and makes it more palatable towards S. salpa according to the results from the preference experiment. Our study shows that S. salpa could develop faster in warmer environments during its most vulnerable stage, increasing its survival but decreasing its dispersal capacity. At the same time, it could increase its preference for P. oceanica in its adult stage, which, together with the reduction of seagrass growth, could considerably intensify the strength of the interaction under warming conditions. All in all, the results of this study have contributed to confirm the relevance of herbivores’ behaviour in the way they exploit P.oceanica, mainly the feeding strategies of S. salpa, and how feedback mechanisms, provide resilience and allow the ecosystem to be maintained in an vegetated state. All of this gets relevant when contextualised within the process of global change, with a probable strengthening of the plant-herbivore interaction. Understanding the sensitivity of the interaction equilibria to each of its components is crucial to decide where to invest conservation efforts in these ecosystems and to be able to anticipate how changes in the contextual conditions may alter the final balance of the interaction.
El papel de la relación consumidor-recurso es la base de la estructura y el funcionamiento de las comunidades ecológicas. La óptica tradicional usada en el estudio de estas interacciones ha tendido a omitir la importancia del comportamiento de las especies, sobre todo en el caso de las interacciones planta-herbívoro. Sin embargo, tanto la forma en la que el herbívoro explota a la planta y como la manera en que ésta responde a esa presión son cruciales para determinar la estabilidad de la interacción. Por lo tanto, las actuaciones del herbívoro y la de la planta, contextualizadas en el entorno en el que tiene lugar la interacción, pueden actuar como mediadores de la resiliencia del sistema. Esta tesis se centra en los ecosistemas de Posidonia oceanica y, concretamente, en la interacción entre esta fanerógama con sus dos principales herbívoros -el pez Sarpa salpa y el erizo de mar Paracentrotus lividus-. En esta tesis se evlaúa la importancia del comportamiento de los herbívoros (los patrones de agregación y las estrategias de alimentación de S. salpa y la dependencia de la cobertura foliar de P. lividus) y la resiliencia proporcionada por los mecanismos de retroalimentación (respuestas directas de la planta y procesos indirectos del ecosistema) bajo condiciones cambiantes resultantes del cambio global. Desentrañar estos componentes de la interacción nos permite evaluar su sensibilidad a cada uno de los dichos componentes y comprobar la respuesta y la resiliencia del sistema bajo diferentes condiciones. En el capítulo 1 se muestra la importancia del tamaño del cuerpo de los individuos de Sarpa salpa en sus tasas de consumo individual, en sus patrones de agregación y en las estrategias alimenticias de grupos, además de las potenciales consecuencias de estos procesos sobre la fanerógama Posidonia oceanica. Por un lado, cuanto mayores son los individuos, mayores tasas de consumo muestran. Por otro, los individuos de S.salpa tienden a agregarse con conspecíficos de la misma talla, mientras que el tamaño de los grupos se relaciona positivamente con la talla de los individuos que lo forman. Además, las estrategias de alimentación aumentan en complejidad con el tamaño del grupo y tienden a focalizarse en puntos muy concretos de la pradera. Así, a medida que los individuos crecen, aumentan su potencial impacto en la fanerógama, tanto por su capacidad de consumo como la formación de grandes bancos capaces de concentrar su herbivoría en áreas muy concretas de las praderas. Esta distribución de la herbivoría puede provocar una heterogeneidad espacial con consecuencias sobre el funcionamiento del ecosistema dominado por P. oceanica En el capítulo 2 se comprueba la existencia de una serie de mecanismos reguladores surgidos de un episodio de herbivoría intensa que aportan resiliencia al sistema de Posidonia oceanica una vez disminuida su bóveda foliar. Cuatro de los mecanismos evaluados funcionan como mecanismos de retroalimentación, siendo uno de ellos desplegado activamente por la planta (crecimiento compensatorio) mientras que los tres restantes (preferencia por un recurso alternativo, incremento del riesgo de depredación y disminución del número de erizos por competencia por el recurso y pérdida de cobertura) se desencadenan de forma indirecta y su eficacia se basa en inducir cambios en el comportamiento del herbívoro Paracentrotus lividus. Los resultados obtenidos muestran como P. oceanica es capaz de invertir esfuerzos en recuperar parte de la biomasa foliar perdida, mientras que el mismo sistema es capaz de regular la presión de herbivoría siempre que las condiciones del entorno sean propicias para la aparición de dichos mecanismos. El papel resiliente de estos mecanismos es clave para evitar el potencial colapso de las praderas de P. oceanica bajo el estrés provocado por un episodio de herbivoría intensa. En el capítulo 3 se evalúa el efecto del calentamiento global en la interacción Posidonia oceanica – Sarpa salpa a través de una combinación de aproximaciones de gradiente en campo con experimentos manipulativos de laboratorio. Por un lado, los resultados muestran que el aumento de la temperatura del agua incrementa significativamente las tasas de crecimiento de S.salpa durante su etapa larval, acorta su período en dicha etapa (menos días en la columna de agua) y limita su dispersión, mientras que no muestra ningún efecto en la actividad herbívora durante su fase adulta. Por otro lado, el calentamiento afecta negativamente las tasas de crecimiento de P. oceanica y la vuelve más palatable frente a S. salpa de acuerdo con los resultados en el experimento de preferencia. Nuestro estudio muestra que S. salpa podría desarrollarse más rápido en su etapa más vulnerable, aumentando su supervivencia, pero disminuyendo su capacidad de dispersión, mientras que podría incrementar su preferencia por P. oceanica en su etapa adulta, lo que, junto con la reducción del crecimiento de la fanerógama, podría intensificar considerablemente la fuerza de la interacción. En definitiva, los resultados de esta tesis han servido para constatar la relevancia del comportamiento de los herbívoros en su forma de explotar el recurso, principalmente las estrategias de alimentación de S. salpa, y como los mecanismos de retroalimentación aportan resiliencia y permiten al ecosistema mantenerse en un estado óptimo. Todo ello cobra más importancia al contextualizarlo dentro del proceso del cambio global, dado el probable fortalecimiento de la interacción planta-herbívoro. Conocer la sensibilidad de la interacción a cada uno de los componentes es crucial para decidir donde hay que invertir los esfuerzos de conservación en estos ecosistemas y poder así anticiparnos a como los cambios en las condiciones de contorno pueden alterar el equilibrio final de la interacción.

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García, Aguirre Ana I. "An evaluation of cognitive deficits in a rat-model of Huntington's disease." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8827.

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The purpose of this thesis was to develop methodology by which treatments for the cognitive impairments in Huntington's disease (HD) could be tested. As such, the thesis focused mainly on evaluating rats with quinolinic acid (QA) lesions of the striatum, as this manipulation mimics some aspects of the neural damage in Huntington's disease, to try to identify cognitive deficits of HD resulting from cell loss in the striatum. In the first part (Chapters 3-5), the role of the striatum in implicit memory was investigated. Chapter 3 compared the performance of rats and humans on a reaction time task that evaluated implicit memory by presenting visual stimuli with differing probabilities which change over time. Although rats made higher percentage of incorrect responses and late errors, both groups showed a similar pattern of reaction times. Chapter 4 investigated whether implicit memory (the computation of probabilities to predict the location of a stimulus) was affected by selective blockade of dopaminergic transmission at the D1 or D2 receptors by SCH-23390 and raclopride, respectively. Reaction times were slower with SCH-23390 and raclopride, but only SCH-23390 reduced errors to the least probable target location. Chapter 5 used the same task to evaluate implicit memory in rats with QA lesions of the dorsomedial striatum (DMS). Implicit memory was not affected by lesions of the DMS, which suggested that once a task that requires implicit memory has been learned, the DMS was not involved in sustaining the performance of the task. The second part of this thesis (Chapter 6), explored the contribution of the DMS in habit formation. DMS lesioned rats did not show habitual responding, and were not impaired in learning a new goal-directed behaviour. The third part (Chapters 7 and 8), investigated the role of the dorsal striatum in reversal learning, attentional set-formation, and set-shifting. Dorsal striatum lesioned rats were not impaired in reversal learning, but had a diminished shift-cost, which suggested that dorsal striatum lesions disrupted the formation of attentional sets. These results showed that although QA lesions of the dorsal striatum mimic some aspects of the neural damage in HD, they did not result in the same cognitive deficits observed in patients with HD, at least using the tasks presented in this thesis. However, other animal models of HD could be evaluated using the different tasks presented in this thesis to continue the search of a reliable animal model of HD in which treatments for the disease could be evaluated.

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Ahonen, Heidi. "Population structure and mating system of the Australian sea lion (Neophoca cinerea)." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA11T059/document.

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Le lion de mer Australien a un cycle de reproduction non-annuel et asynchrone entre les colonies.Contrairement aux autres pinnipèdes, ce système unique offre l’opportunité aux mâles de se reproduiredans plusieurs sites lors d’une saison de reproduction. L’accès des mâles à plusieurs sites dereproduction pourrait contrecarrer le fort degré de structure génétique de population chez les femellesdûe à une fidélité extrême au site de reproduction. J'ai utilisé deux méthodes indépendantes maiscomplémentaires, moléculaire et acoustique, afin d’étudier la structure de la population et le systèmede reproduction. Pour l'analyse moléculaire, j'ai développé une banque de microsatellites spécifiques àl'espèce. Ces marqueurs ont été utilisés pour examiner le flux génétique des mâles dans les différentescolonies de reproduction, le succès reproducteur, et les taux de paternité inter- et intra-colonies. Deplus, j'ai mesuré la variation géographique dans les cris des mâles, ce qui représente une approchealternative pour mesurer les convergences/divergences entre colonies. J'ai montré que si les mâlesprésentent une certaine dispersion entre colonies, elle est limitée à une courte échelle en dépit del’opportunité des mâles de se reproduire dans différents sites. Les analyses acoustiques des cris demâles ont révélé des variations géographiques significatives entre colonies, qui ne reflètent pas lastructure génétique. Les analyses de paternité indiquent un faible taux de polygynie, la majorité desmâles ne produisant qu’un ou deux jeunes par saison. Des stratégies alternatives de reproduction(nomade ou sédentaire) sont présentes dans cette espèce, certains mâles se déplaçant activement entredifférentes colonies proches. Le système de reproduction unique du lion de mer Australien semblefortement influer à la fois les modalités de dispersion, mais aussi la structure de population et lesystème de reproduction
The Australian sea lion has a non-annual and asynchronous breeding cycle across geographically closecolonies. In contrast to other pinnipeds, this unique reproductive system provides the opportunity formales to breed in different colonies during one breeding cycle. Male mating success across differentcolonies could counteract the high degree of structure driven by extreme site fidelity in females. I usedtwo, independent but complementary methods, molecular and acoustic to investigate their populationstructure and mating system. For molecular analysis I developed a species-specific microsatellitelibrary. These markers were used to examine the extent and rate of male mediated gene-flow acrossbreeding colonies but also to determine the breeding success and paternity both within and acrossspatially close colonies. Also, I investigated the geographical variation in male barking call. Thisrepresents an alternative approach to measure boundaries and relationships between colonies. Malesexhibit dispersal; however, this is limited to remarkably small scale in regards to the high potential fordispersal and opportunity to breed in different colonies. Acoustic analyses of the male barking callsrevealed significant geographical variation across sites; however this observed acoustic variation didnot reflect the genetic structure. Paternity analyses revealed that males display relatively modest ratesof polygyny with the majority of successful males siring only one or two pups per breeding cycle. Thepresence of alternative mating strategies (roaming vs staying) is apparent in this species with somemales actively moving and breeding between close colonies. It appears that the unique breedingbiology of Australian sea lion influences dispersal patterns, population structure and mating system

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Zajková, Zuzana. "Movement ecology in pelagic seabirds." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/668688.

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Movement is a fundamental component of behaviour and thus both are inextricably linked. Variation in movement patterns usually reflects different behaviours, including those most glaring, such as foraging, dispersal, migration, social interaction, mate search or escaping from predators. The way individuals allocate their time budget to different behaviours within circadian rhythm and over the annual life cycle will ultimately provide knowledge about evolutionary processes and adaptive capacity, also important to proper conservation actions of endangered species. Among highly mobile marine megafauna, seabirds represent suitable model species to address key questions about movement and behaviour. The study of year-round movements of seabirds has been addressed over the last 20 years with the wide deployment of light-level geolocators equipped with saltwater immersion sensors. However, wet-dry data provided by such loggers seem underused so far despite their usefulness to provide important insights on a variety of dimensions of seabird ecology. The main aim of this thesis was to provide new insights into the factors shaping seabird behaviour. The thesis encompasses several aspects of seabird at-sea ecology of 4 different species spread over the Atlantic Ocean: Boyd’s shearwater (Puffinus boydi), Common tern (Sterna hirundo), Atlantic petrel (Pterodroma incerta) and Cory’s shearwater (Calonectris borealis). In Chapter 1 we reveal the timing of major events over the annual life cycle, migratory routes and place on the map the non-breeding areas of a little-known tropical seabird endemic to Cape Verde Islands, the Boyd’s Shearwater. We show that Boyd's shearwaters perform longitudinal migrations to the oligotrophic central North Atlantic Ocean for the non-breeding season, in contrast with closely-related taxa that rely on most productive waters. In Chapter 2, we show that Common terns breeding in continental Europe spread over the West African coast for wintering, but females winter further north and use offshore waters whereas males winter further south and remain nearby the coastline. Behavioural budgets of Common terns were shaped within circadian and circa-annual rhythms. In Chapter 3 we describe in detail the phenology of the Atlantic petrel, showing that breeding success likely shapes the timing of major life-history events and behavioural patterns year round. We did find evidence of carry-over effects, since failed breeders advanced their post-breeding migration, remained longer in the wintering area, and advanced pre-breeding migration comparing to successful breeders. Breeding success did not affect the selection of wintering areas, as all birds relied on the South American shelf slope during different stages of the annual cycle. In Chapter 4, we demonstrate how geolocator-immersion loggers constitute a powerful and irreplaceable source of information to study seabird behaviour. We present a novel approach to infer a diverse array of behaviours based uniquely on wet-dry data, built upon a set of state-of-the-art unsupervised machine learning algorithms that reduce multidimensional data to a bidimensional behavioural space, from which different behaviours can be drawn. We applied the protocol on wet-dry data from Cory’s shearwater. Through these means, we can inspect in great detail and from manifold perspectives the behavioural patterns at individual and population level, highlighting how seasonal constraints shape behavioural budgets and behavioural strategies. We use data visualization tools such as actograms and behavioural landscapes to get new insights, highlighting that such tools constitute an effective method to visualize behaviour of seabirds inferred from wet-dry data from manifold perspectives. Geolocator-immersion sensors currently remain as the most cost-effective balanced tracking devices to track seabird species over the entire annual cycle while ensuring the welfare of tagged individuals. Thus, results compiled in this thesis should encourage researchers to incorporate the use wet-dry data within hypothesis-driven frameworks, which surely would contribute to increase our knowledge of seabird ecology at sea.
El movimiento es un componente fundamental del comportamiento animal, estando ambos íntimamente entrelazados. Variaciones en los patrones de movimiento normalmente reflejan cambios de comportamiento, incluyendo aquellos más conspicuos como la búsqueda de alimento, la dispersión, la migración, las interacciones sociales, la búsqueda de pareja o la huida ante depredadores. La forma en la que los patrones comportamentales se ajustan en el tiempo de acuerdo a los ritmos circadianos y a lo largo del ciclo anual puede ayudarnos a entender, en última instancia, los procesos evolutivos y la capacidad de adaptación de las poblaciones animales, algo también importante de cara al desarrollo de medidas de conservación de especies amenazadas. Las aves marinas representan un modelo especialmente adecuado para el estudio de la ecología comportamental y del movimiento. Estudiar los movimientos de las aves marinas en mar abierto ha sido posible en las dos últimas décadas gracias a la normalización en el uso de geolocalizadores por niveles de luz. Aunque buena parte de los modelos de geolocalizador es capaz de registrar datos de conductividad en agua salada (seco/húmedo), esta información parece infrautilizada a la luz de la literatura publicada. Sin embargo, los datos de conductividad son enormemente útiles para el estudio de multitud de aspectos sobre la ecología de las aves marinas. Esta tesis aborda diferentes aspectos de la ecología en mar abierto de 4 especies de aves marinas del océano Atlántico: la pardela chica de Cabo Verde (Puffinus boydi), el charrán común (Sterna hirundo), el petrel atlántico (Pterodroma incerta) y la pardela cenicienta (Calonectris borealis). En el Capítulo 1 revelamos la fenología, rutas migratorias y área de invernada de una especie tropical de pequeño tamaño, la pardela de Cabo Verde, endémica de dicho archipiélago. A diferencia de especies cercanas, los individuos de esta especie realizan una migración longitudinal hasta las aguas oligotróficas del centro del Atlántico Norte. En el Capítulo 2, mostramos que los charranes comunes que crían en Europa migran hasta la costa oeste de África para invernar, aunque las hembras se quedan más al norte y en ambientes más marinos, y los machos más al sur y en ambientes costeros. El comportamiento en ambos sexos parece regulado por ritmos circadianos y anuales. En el Capítulo 3, desgranamos la fenología del petrel Atlántico, una especie endémica del archipiélago de Tristán da Cunha, mostrando que el éxito reproductor probablemente moldea la sucesión de eventos fenológicos y los patrones de comportamiento. Incluso encontramos evidencias de efectos arrastrados, puesto que los animales que fracasaron en la cría adelantaron la migración, permanecieron más tiempo en la zona de invernada, y retornaron antes a las colonias de cría. Tanto los animales que tuvieron éxito como los que fracasaron en la cría invernaron en aguas de la plataforma continental de América del Sur y Patagonia. En el Capítulo 4, presentamos un nuevo protocolo analítico basado en algoritmos de aprendizaje automático que utiliza únicamente datos de conductividad. Mediante su aplicación sobre datos de pardelas cenicientas, demostramos que los datos de conductividad constituyen una poderosa herramienta para el estudio de las aves marinas, permitiendo desglosar a un nivel sin precedentes su comportamiento a diversas escalas: espacial (de viajes cortos a migraciones anuales), temporal (de días a años) y poblacional (de individuos a poblaciones). El análisis también nos permite resaltar los diferentes elementos que moldean el comportamiento animal a diferentes escalas temporales, utilizando para ellos potentes herramientas de visualización de datos como los actogramas. El conjunto de resultados expuestos en esta tesis debe alentar a los investigadores a utilizar más frecuentemente los datos de conductividad, lo cual contribuiría a aumentar nuestro conocimiento sobre la ecología de las aves marinas.

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Di, Franco Eugenio. "Impact de la pollution sonore sur les juvéniles de sparidés méditerranéens." Thesis, Université Côte d'Azur, 2021. http://www.theses.fr/2021COAZ4089.

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L’environnement marin est extrêmement sonore et les animaux marins utilisent ces sons pour plusieurs activités essentielles (e.g., communiquer, s’orienter, se nourrir). Depuis la révolution industrielle, les activités humaines en mer n’ont cessé d’augmenter, ce qui a entrainé la production de sons pénétrant dans le milieu marin. La pollution sonore marine (PSM) anthropogénique se définit comme l’introduction dans l’environnement de sons causant des effets néfastes sur la vie marine. Les impacts de la PSM ont été traditionnellement étudiés sur les mammifères marins et plus récemment sur les poissons et invertébrés. Ces études, effectuées surtout sur des individus adultes, ont montré des effets néfastes de la PSM allant de légers changements comportementaux ou physiologiques jusqu’à des lésions internes ou externes, voire la mort. Cependant, il existe encore de multiples lacunes dans les connaissances qui nécessitent d’être comblées afin de mieux comprendre l’impact de la PSM sur les individus jusqu’aux écosystèmes, cela implique aussi de développer de nouveaux indicateurs et biomarqueurs des perturbations liées à la PSM.Les buts de cette thèse ont été de : 1) passer en revue les informations existantes et les lacunes concernant l’impact de la PSM sur les poissons et invertébrés d’un hotspot de PSM, la Mer Méditerranée ; 2) étudier les relations qui existent entre la PSM et plusieurs variables bioécologiques de sparidés juvéniles (Pisces : Sparidae) directement sur le terrain. Plus précisément, 4 zones ont été étudiées, correspondant à l’habitat d’installation des sparidés et situées le long d‘un gradient de PSM sur la Côte d’Azur (NW de la Mer Méditerranée). Des hydrophones ont été couplés à de l’échantillonnage photographique pour déterminer la PSM. Ensuite, des recensements visuels ont été effectués pour déterminer d’éventuelles relations entre la PSM et la structure de l’assemblage de sparidés juvéniles, la densité des différentes espèces et le comportement grégaire. Enfin, des spécimens de Diplodus sargus et Oblada melanura ont été échantillonnés pour étudier les relations entre la PSM et la croissance, la forme des otolithes, le comportement alimentaire, l’ingestion de microplastiques et les réserves énergétiques.La revue bibliographique a révélé de multiples lacunes (e.g. peu d’études effectuées directement sur le terrain et encore moins étudiant l’impact sur les stades de vie précoces) qui nécessitent d’être comblées afin de mieux comprendre les impacts de la PSM sur la vie marine de Méditerranée. Les recensements visuels ont révélé une relation significative entre la PSM et l’assemblage de sparidés juvéniles, avec la densité d’une espèce qui diminue avec l’augmentation de la PSM, tandis que celle d’autres espèces augmente ou reste inchangée. Les analyses des spécimens échantillonnés ont montré que la PSM n’affecte pas la croissance des individus, mais elle peut modifier la forme des otolithes, les comportements alimentaires et l’ingestion de microplastiques. De plus, des analyses préliminaires ont été effectuées sur le métabolisme énergétique et le comportement grégaire mais elles requièrent plus d’investigations pour en tirer de robustes conclusions. Globalement, ces résultats ont mené à l’hypothèse que la faible profondeur caractérisant l’habitat d’installation (surtout pour les espèces du genre Diplodus) pourrait atténuer la PSM. Cependant, certains résultats suggèrent que les sparidés juvéniles seraient tout de même affectés par la PSM.Etant donné que l’installation est une des phases les plus cruciales dans la vie des sparidés, il est primordial de déterminer les impacts de la PSM sur les juvéniles pour mieux comprendre la persistance et les dynamiques des populations, qui pourraient ensuite affecter des communautés et des écosystèmes entiers. Cette thèse offre ainsi de nouveaux outils, idées et perspectives pour mieux comprendre comment la PSM pourrait affecter les stades de vie précoces de poissons côtiers
The underwater marine environment is full of sounds which are used by marine animals for many essential activities (e.g., communication, orientation, feeding). Since the industrial revolution, human activities at sea have been ever increasing, inducing the production of sounds underwater. Anthropogenic marine noise pollution (MNP) is defined as the introduction in the environment of sounds producing deleterious effects on marine life. The impacts of MNP have been traditionally studied on marine mammals and more recently on fishes and invertebrates. These studies, mostly conducted on adult individuals, highlighted multiple negative impacts of MNP ranging from mild behavioral or physiological changes up to internal or external injuries and even death. However, there are still important knowledge gaps to fill to better understand the impacts of MNP from single organisms up to entire ecosystems, also implying to develop new indicators and biomarkers of MNP-related disturbance.The aims of the present thesis are: 1) to review the existing information and knowledge gaps about the impact of MNP on fishes and invertebrates in a MNP hotspot represented by the Mediterranean Sea; 2) to assess the relationships between MNP and multiple bio-ecological variables related to settlers of sparid fishes (Pisces: Sparidae) directly in the field. More specifically, 4 locations corresponding to settlement habitats of sparid fishes across a MNP gradient in the French Riviera (NW Mediterranean Sea) have been investigated. Hydrophones have been used in combination with photo-sampling to characterize the MNP in each location. Then, visual censuses have been performed to assess the putative relationships between MNP and the assemblage structure of sparid settlers, single species density and schooling behavior. Finally, specimens of Diplodus sargus and Oblada melanura have been collected to investigate relations between MNP and growth, otolith shape, feeding behavior, microplastic ingestion and energy reserves.The review of the bibliography highlighted multiple gaps in the available knowledge (e.g. few studies have been conducted directly in the field and even less assessed impacts on early life stages) which needed to be filled to better understand the impact of MNP on marine life in the Mediterranean Sea. The results of visual censuses revealed a significant relationship between MNP and the assemblage of sparid settlers, with the density of one species decreasing with increasing MNP, while the density of the other species increased or did not change. The analyses performed on the collected specimens highlighted that MNP does not affect individual growth, while it may modify the shape of otoliths, feeding habits as well as the ingestion of microplastics. Also, some preliminary analyses have been conducted on energy metabolism and schooling behavior, but they require deeper investigations to draw more robust conclusions. Overall, these results led to the hypothesis that the shallow depth of settlement habitats (especially for Diplodus species) may reduce MNP. Nevertheless, some results suggest that sparid settlers might still be affected by MNP.Because settlement is one of the most crucial phases in the life history of sparid fishes, understanding the possible impacts of MNP on settlers is of paramount importance to better understand population persistence and dynamics, which may ultimately affect whole communities and ecosystems. This thesis, therefore, offers new tools, ideas, and perspectives to better understand how MNP may affect early life stages of coastal fishes

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Cayuela, Hugo. "Réponses à un environnement spatio-temporellement variable : sexe, dispersion et tactiques d'histoire de vie chez le sonneur à ventre jaune (Bombina variegata, L.)." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1034/document.

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Examiner les liens existant entre la variabilité environnementale, les traits d'histoire de vie, la dispersion et les décisions d'accouplement est un enjeu central en Ecologie et en Evolution. J'ai exploré ces questions chez un amphibien, le sonneur à ventre jaune (Bombina variegata). Dans le premier volet de ma thèse, je me suis intéressé à l'influence des variations spatiotemporelles de l'environnement sur les patrons de covariation entre les traits d'histoire de vie, la dispersion et les types comportementaux à l'échelle inter-populationnelle. J'ai examiné comment le degré de stochasticité interannuel de l'habitat de reproduction régule le positionnement des populations le long du slow-fast continuum et génère des syndromes de dispersion parmi les populations. J'ai ensuite analysé les conséquences de ces syndromes sur les patrons de différenciation génétique au sein des populations. Dans le second volet de ma thèse, je me suis intéressé au rôle de la canalisation environnementale dans la stratégie d'histoire de vie de B. variegata et j'ai évalué comment diverses formes de variations météorologiques pouvaient affecter la dynamique de différentes populations. Dans chacune d'elles, j'ai mesuré l'impact de facteurs météorologiques sur des paramètres démographiques tels que la survie, le recrutement et les probabilités de reproduction. Dans le troisième et dernier volet de ma thèse, je me suis intéressé au choix d'accouplement des femelles, en examinant successivement les hypothèses de bons gènes et de gènes compatibles puis en me focalisant sur le rôle de la qualité et de la disponibilité des sites de reproduction sur les décisions d'accouplement des femelles
Investigating the links between environmental variability and life history traits, dispersal and breeding decisions is critical challenge for ecologists. I have examined this issue in anuran, the yellow-bellied toad (Bombina variegata). In the first part of my thesis, I have examined the influence of spatio-temporal variation of the environment on the covariation patterns between life history traits, dispersal and behavioral types at inter-population scale. I have investigated how the level of breeding habitat stochasticity may regulate the position of B. variegata populations along the slow-fast continuum and may promote dispersal syndromes among populations. Then I have analyzed the consequence of such dispersal syndromes on population genetic differentiation. In the second part of my thesis, I have focused on the role of the environmental canalization in the life history strategy of B. variegata and I have evaluated how various forms of weather variation (mean and extreme events) could affect the dynamics of different populations. In each studied populations, I have quantified the impacts of weather variation on various demographic parameters as survival, recruitment and breeding probabilities. In the third part of my thesis, I have investigated female mate choice in B. variegata by successively examining good genes and compatible gene hypotheses, and then by evaluating the role of breeding habitat quality and availability on mating decisions

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Herrero, Ramón María Jesús. "Ritmos de actividad motora, comportamiento alimentario e influencia de la melatonina exógena en peces teleósteos." Doctoral thesis, Universidad de Murcia, 2007. http://hdl.handle.net/10803/10856.

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La presente Tesis Doctoral tiene como objetivo profundizar en los conocimientos sobre ritmos biológicos y comportamiento alimentario de tres especies de peces teleósteos de interés en acuicultura: tenca (Tinca tinca), trucha alpina (Salvelinus alpinus) y lubina (Dicentrarchus labrax).Con este fin se ha investigado la influencia de factores bióticos y abióticos en la sincronización de los ritmos de actividad locomotora y alimentaria, así como el carácter endógeno y/o exógeno de estos ritmos. A su vez, se ha profundizado en el comportamiento individual de truchas alpinas mantenidas en grupo, mediante una nueva metodología que permite estudiar los ritmos de demanda voluntaria de alimento y la autoselección dietaria de los individuos. Asimismo, se ha analizado la influencia de los niveles endógenos de melatonina, modificados mediante la administración de melatonina exógena y de su aminoácido precursor (triptófano) en la dieta, sobre la concentración de cortisol y el ritmo de actividad locomotora en lubina.
This Doctoral Thesis deeps into the knowledge about biological rhythms and feeding behaviour in three teleostean fish species of interest in aquaculture: tench (Tinca tinca), Arctic charr (Salvelinus alpinus) and European sea bass (Dicentrarchus labrax). With this aim, the influence of biotic and abiotic factors has been researched in the field of synchronization of locomotor and feeding rhythms, as far as the endogenous or exogenous character of these rhythms. Moreover, individual feeding behaviour of Arctic charr kept in groups has been studied trying a new methodology which allows the monitoring of feeding demands and dietary self-selection of individuals. Furthermore, influence of endogenous melatonin modified through exogenous melatonin and its precursor amino acid (tryptophan) administration in the diet, in the cortisol levels and locomotor activity rhythms in sea bass were analysed.

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Orgeret, Florian. "Ontogenèse de la recherche alimentaire durant la phase juvénile : cas des prédateurs plongeurs." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS006/document.

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La période juvénile d’espèces longévives demeure peu connue malgré son importance pour la démographie et la conservation des populations. L’objectif de cette thèse a été d’étudier le comportement de dispersion et de nourrissage de 52 juvéniles de trois espèces de prédateurs marins plongeurs des Terres Australes et Antarctiques Françaises (les manchots royaux, les manchots empereurs et les éléphants de mer du Sud) pendant quasiment 1 an après leur indépendance. L’approche a été basée sur l’utilisation de balises retransmettant en direct la localisation et des données de plongée. Les juvéniles de ces trois espèces présentèrent des dispersions sur de très grandes distances dans l’Océan Austral, avec au départ des composantes d‘orientation semblant en partie innées. Le rôle des courants océaniques et des zones frontales est apparu important. Les juvéniles montrèrent aussi une ségrégation spatiale prononcée avec les adultes. Les juvéniles présentèrent d‘impressionnantes capacités de plongée seulement quelques jours après leur départ. Cependant, si leurs capacités de plongée et d‘acquisition de nourriture augmentèrent progressivement avec le temps, elles n‘atteignirent jamais totalement les capacités des adultes. Certains juvéniles ne parvinrent pas à augmenter ces capacités alors que leur environnement devint moins favorable et apparemment décédèrent en mer, vraisemblablement par inanition. La première année en mer apparait alors comme une phase critique puisqu'une mortalité apparente fut observée pour chaque espèce. Cette thèse apporte des éléments de compréhension nouveaux sur l’ontogenèse de la dispersion et de la recherche alimentaire des prédateurs marins plongeurs
The juvenile phase of long lived-species is poorly understood despite its critical importance for the future of animal populations. Thanks to new bio-technologies, in this thesis we managed to monitor the ontogeny of foraging behaviour in 52 juveniles from 3 deep-diving marine predator species (king penguins, emperor penguins and southern elephant seals) in the French Southern territories over the first year after their independence. The juveniles of these 3 species showed a very large dispersion range over huge distances in the Southern Ocean. Their dispersion was characterized at departure by partially innate behaviour in their orientation preferences. Juveniles showed a strong dependency to the local oceanic currents orientation and frontal zones. More, they showed a spatial segregation with adults. Juveniles were quickly able to dive very deep. Their diving and foraging skills increased progressively with time. However, juveniles never completely reached the efficiency of adults, even after one year at sea. Some juveniles did not manage to increase their foraging skills while their environment became less productive; these juveniles may have died at sea, probably because of starvation. The first year at sea appears thus to be critical for the 3 studied species, as substantial mortality occurred in each case. This thesis presents new information about the ontogeny of dispersion and the foraging behaviour in marine deep-diving predators

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"The Development of Adult Sex-typed Social Behavior in Lemur catta." Doctoral diss., 2012. http://hdl.handle.net/2286/R.I.14674.

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abstract: Unanswered questions about the evolution of human gender abound and are salient across the anthropological disciplines and beyond. Did adult sex-typed behavioral tendencies actually evolve? If so, when? For what purpose? The best way to gain insight into the evolution of human gender is to understand the evolution and development of sex-typed behavior in comparative primate taxa. Captive research indicates that there are many proximate factors likely to shape the development of sex-typed behavior in non-human primates—prenatal and postnatal endocrinological experience, social experience, ecological factors, and their interactions. However, it is largely unknown how sex-typed behavior proceeds and is shaped by those factors in evolutionarily salient environments. This study investigated one—whether extrinsic sexually differentiated social interactions are likely influential in the development of adult sex-typed behavior in wild-living Lemur catta. Little is known about sex-typed development in this species or in strepsirrhines in general. This research therefore addresses an important phylogenetic gap in our understanding of primate sex-typed development. Behavioral observations were carried out on mixed cross-sectional sample of adult females (n=10), adult males (n=8), yearling females (n=4), yearling males (n=4), and newborn females (n=16) and males (n=14) at Beza Mahafaly Special Reserve in southwest Madagascar from September 2008 to August 2009. Twenty-three sex-typed behaviors were identified in adults using linear mixed effects models and models of group response profiles through time. Of those, only eight had a pre-pubertal developmental component. Infants did not exhibit any sex differences in behavior, but juveniles (prepubertal, weaned individuals) resembled adults in their (relatively few) patterns of expression of sex-typed behavior. Most adult sex-typed behaviors in this species apparently develop at or after puberty and may be under gonadal hormone control. Those that develop before puberty do not likely depend on extrinsic sexually differentiation social interactions for their development, because there is no clear evidence that infants and juvenile male and females are not treated differently by others according to sex. If sexually differentiated social interactions are important for sex-typed behavioral development in subadult ,italic>Lemur catta, they are likely intrinsically (rather than extrinsically) driven.
Dissertation/Thesis
Ph.D. Anthropology 2012

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Dissertations / Theses on the topic 'Animal Sex Behavior'

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