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Bradshaw, Richard H. "Agonistic behaviour and individual recognition in groups of laying hens." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276581.
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Hobson, Helen. "Serotonergic modulation of social and agonistic behaviour in male mice." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333815.
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Schoening, Barbara. "Evaluation and prediction of agonistic behaviour in the domestic dog." Thesis, University of Bristol, 2006. http://hdl.handle.net/1983/23316504-ed58-4004-8a77-0242644c2c4d.
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To date, the strategy in many countries for prevention of danger originating from dogs, has been a) to ban certain breeds which are supposed to be more aggressive than others, and b) to apply a variety of temperament tests to dogs of all breeds, with the aim of detecting those with elevated aggressiveness. There is some scientific literature in this field, but empirical hypothesis testing is still scarce. The first part of this thesis examines whether "dangerous dogs" can be reliably distinguished from "normal" dogs. In a formal test of aggressive and unacceptable social behaviour, designed to predict aggressive behaviour later in the dog's life, six distinct sets of releasers for aggression were identified (Groups A-F), and a further three in a supplementary test conducted in-home (Groups G-I). Breed, age, sex, and previous training were found to influence the quality and quantity of the behaviour shown in the individual subtests. Responses to Group D (dogs) were associated with previous history of biting dogs; responses to Groups B (threats from humans) and E (play) were associated with previous history of biting people. Both might therefore be predictive of future risk of biting. In addition to aggressive responses, an ethogram was used to characterise the dogs' behaviour; the majority appeared to display aggressive behaviour motivated by a stressful state and/or uncertainty. In the second part, the behavioural development of four litters of Rhodesian Ridgebacks was recorded in weeks four to eight of life, focussing on behaviour shown in dyadic interactions with siblings. When the same dogs were tested as adults, puppy behaviour proved not to be a predictor for any behaviour patterns shown in conflict situations, Biases in the test, and the implications of the results for keeping and breeding dogs, and for prevention of danger arising from dogs, are discussed.
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Wilson, Jeremy David. "The functions of agonistic interaction, social dominance and display in a winter population of the great tit, Parus major L." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/14677.
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Black, J. M. "The pair-bond, agonistic behaviour and parent-offspring relationships in barnacle geese." Thesis, Cardiff University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378102.
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Sneddon, Lynne Ure. "The physiological effects of agonistic behaviour in the shore crab, Carcinus maenas (L.)." Thesis, University of Glasgow, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264141.
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Tan, Shenton S. L. "Agonistic behaviour in finishing pigs (Sus scrofa) following mixing : its effect on productivity." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28408.
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The effect of mixing unfamiliar finishing pigs (Sus scrofa) on agonistic behaviour and productivity over a 3 week period was investigated. Nine groups of six pigs were allocated to one of three treatments and eight groups of six pigs to the fourth treatment. In the first treatment (unmixed) littermate groups were moved into a new pen and in the second treatment (3:3 mixed) 3 pigs from one littermate group were mixed with 3 pigs from a second littermate group. The third treatment (Stresnil-treated) was similar to the second treatment but pigs were injected with the tranquilizer Stresnil (azaperone) prior to mixing. In the fourth treatment (5:1 mixed) groups of five pigs were introduced into a pen already occupied by either a single relatively light weight pig or a relatively heavy weight pig. Intense fighting was displayed by the regrouped pigs immediately following mixing, while unmixed and Stresnil-treated pigs generally went to sleep.
During feeding periods, initiated aggression was the most common agonistic behaviour exceeding aggressive responses and submissive responses by a factor of up to 14. In mixed groups initiated aggression was significantly higher than in unmixed groups. Administration of Stresnil appeared to disrupt the animals' behavioural repetoire by delaying aggression, retarding social hierarchy establishment and depressing productivity. Prior occupancy of pen space also appeared to influence aggressive behaviour. Over the entire three week sample period, average daily weight gains (ADG) of all three mixed treatments were significantly less than unmixed groups. The differences were significant during the first week but not in the second or third weeks. The mixed groups were also poorer converters of feed during the first week and over the three week period. Stresnil-treated pigs, on average, exhibited the poorest productivity of the mixed treatments. The economic costs of raising mixed groups from an initial weight of 76 kg to a standard final weight of 95 kg as a result of their reduced weight gain and feed efficiency, was substantial: $2.92 per pig for Stresnil-treated groups; $1.43 per pig for 3:3 mixed groups; and $1.13 per pig for 5:1 mixed groups. Assuming that growth rates remain the same, extrapolation of the data to a market weight of 102 kg resulted in overall costs of $3.50 per pig for Stresnil-treated groups, $1.94 per pig for 3:3 mixed groups and $1.54 per pig for 5:1 mixed groups.<br>Land and Food Systems, Faculty of<br>Graduate
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Ramos, Daniela Maria Justino Alves. "Intraspecific agonistic behaviour during settlement events of a marine invertebrate with a biphasic life cycle." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16834.
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Mestrado em Ecologia Aplicada<br>Cannibalism is a well-known behaviour among several invertebrate marine species and may play a relevant role in population dynamics and distribution. In this study we tested if this behaviour occurs at key moments of the complex life cycle of a decapod, namely at settlement and early post-metamorphosis. We collected wild megalopae of the brachyuran crab Carcinus maenas at Ria de Aveiro (Portugal) and at laboratory conditions tested the survival of megalopae stocked at different densities and under contrasting conditions of habitat and food availability. We also tested if cannibalism could be observed between megalopae and first, second and third instar juvenile crabs. Our results showed that megalopae only display cannibalism towards conspecifics at the same life stage under high densities scenarios. The occurrence of cannibalism towards megalopae was immediate and more significant with juveniles on the third crab stage (C3) when compared with the first and second juvenile crab stage (C1 and C2). This study allowed to perceived that during high settlement peaks, the performance and survival of megalopae is not affected by possible cannibalistic interactions among other megalopae. However, the structure and number of the adult population may not correspond to the potential settlement of the larvae when conspecifics of previous events, such as juvenile C3 are present in the same place, due to occurrence of cannibalism.<br>O canibalismo é um comportamento intraespecífico observado entre muitas espécies de invertebrados marinhos, introduzindo alterações na dinâmica e distribuição das populações. Neste estudo pretendemos testar se este comportamento pode ser observado durante o assentamento e pós-assentamento de um decápode com um ciclo de vida complexo. Megalopas selvagens do caranguejo braquiúro Carcinus maenas foram recolhidas na Ria de Aveiro (Portugal) e em condições de laboratório, testou-se a sua sobrevivência quando expostas a diferentes densidades, complexidade de habitat e disponibilidade de alimento. Foi também testada a ocorrência de canibalismo dos três primeiros estágios de juvenis para com conspecíficos no estado larvar de megalopa. Os resultados experimentais revelaram que o canibalismo não é comum entre megalopas, sendo apenas influenciado quando estão presentes em grandes densidades. Os juvenis no terceiro estágio de caranguejo (C3) apresentaram comportamentos canibalísticos imediatos e mais significativos quando comparados com os juvenis do primeiro e segundo estágio de caranguejo (C1 e C2). Os resultados apresentados permitiram deste modo perceber que durante elevados picos de assentamento, o desempenho e sobrevivência das megalopas não é afetado por possíveis comportamentos canibalísticos entre estas. No entanto, a estrutura das populações adultas pode não corresponder ao potencial de assentamento das larvas quando coespecíficos de eventos anteriores, como por exemplo, juvenis C3, se encontram presentes no mesmo local, devido à ocorrência de canibalismo.
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Backström, Tobias. "Roles of Arginine-Vasotocin and Corticotropin-Releasing Hormone in Stress Responses and Agonistic Behaviour of Rainbow Trout." Doctoral thesis, Uppsala universitet, Jämförande fysiologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8485.
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The neuropeptides arginine-vasotocin (AVT) and corticotropin-releasing hormone (CRH) are involved in the hypothalamic-pituitary-interrenal (HPI) axis. During stress, the HPI axis is activated and cortisol is released into the blood. In addition to their role in the HPI axis, AVT and CRH also have behavioural effects. The roles of AVT and CRH in stress responses and agonistic behaviour were studied in this thesis, using two different models. In the first model, two strains of rainbow trout (Onchorhynchus mykiss) divergent in stress-induced release of cortisol were investigated. This was done by observing behaviour and stress responses under different conditions. These strains were found to have divergent stress coping strategies based on the observed behaviour and levels of plasma cortisol. This divergence in behaviour could be associated with the CRH system, since the mRNA levels of CRH differed between the strains during stress. However, no differences between strains were observed in AVT or its receptor expressions. In the second model, non-selected rainbow trout were paired and the effect of intracerebroventricular (icv) injections of an active substance (AVT, CRH or the CRH related peptide Urotensin-I (UI)) on fights for dominance was investigated. One fish of the pair received the active substance icv and the other received saline icv. Fish receiving AVT became subordinate in accordance with the suggestion that AVT attenuates aggression in territorial vertebrates. Fish receiving CRH became subordinate whereas UI showed no effect on fights for dominance. Further, both CRH and UI induced an anxiety-related behaviour similar to non-ambulatory motor activity in rats. In addition, CRH appeared to affect the dopaminergic and serotonergic systems. In this thesis, it is suggested that CRH is involved in the behavioural modulation of the stress coping strategies in teleost fish. Further, AVT and CRH seem to act inhibitory on aggressive behaviour.
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Guiasu, Radu Cornel. "Agonistic behaviour patterns and the distribution and status of the Cambarus (Decapoda, Cambaridae) crayfish of Ontario, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0005/NQ27940.pdf.
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Chew, Graeme Lincoln Carleton University Dissertation Psychology. "Development of agonistic behaviour in size-colour classes of rainbow trout (Salmo gairdneri) and brook charr (Salvelinus fontinalis)." Ottawa, 1986.
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Lynch, Karl. "The role of 5-HTâ†3 and 5-HTâ†4 receptors in social and agonistic behaviour in male mice." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343057.
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Buchwalder, Theres. "Effect of familiarity, group size, and floor space availability on agonistic behaviour in fattening turkeys (Meleagris gallopavo) and effect of an analgesic on their activity behaviour." [S.l.] : [s.n.], 2004. http://www.zb.unibe.ch/download/eldiss/04buchwalder_t.pdf.
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Desjardins, Dawn C. "The effects of environmental conditions and brain micro structure on agonistic behaviour displayed in rats subsequent to seizure induction by lithium and pilocarpine." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ31425.pdf.
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Höglund, Erik. "Neuroendocrinology of agonistic interaction and social signalling in Arctic charr (Salvelinus alpinus) : studies on the neuroendocrine regulation of aggressive behaviour, stress responses and skin colour /." Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-4964-6/.
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Faruzzi, Alicia N. "Corticotropin Releasing Factor Receptors and Agonistic Behavior in Syrian Hamsters." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/psych_diss/10.
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Social conflict is a part of everyday life, and it can be a potent stressor for both humans and other animals. In the laboratory, when two Syrian hamsters (Mesocricetus auratus) compete for territory, a dominance hierarchy is quickly formed. Becoming subordinate is a significant stressor resulting in increased release of adrenocorticotropic hormone, β-endorphin, and cortisol. Defeated hamsters will also subsequently fail to display territorial aggression in future social encounters and will instead display increased submissive behavior, even in the presence of a smaller, non-aggressive intruder. This change in behavior is consistent and long-lasting and has been termed conditioned defeat (CD). Corticotropin releasing factor (CRF) is an important neuropeptide in the control of the hypothalamo-pituitary-adrenal (HPA) axis response to stress. It is also involved in a number of behaviors such as anxiety, stress responding, food intake, learning, and memory. The widespread distribution of CRF, CRF-like peptides, and CRF receptors, particularly in brain sites related to anxiety, fear, and stress responses, suggests a role for CRF and CRF-like peptides in modulating emotional responses other than via HPA axis activity. It has also been shown that CRF may have a role in the acquisition and expression of CD. Non-specific and CRF type 2-specific CRF antagonists reduce the acquisition and expression of CD in male hamsters while injection of a CRF type 1-specific antagonist does not. Therefore, the goal of this dissertation was to investigate the role of CRF type 1 and 2 receptors in CD in hamsters and to identify neuroanatomical locations where CRF may be acting. It was found that non-specific or CRF type 1 receptor specific agonists enhance the expression, but not acquisition, of CD. Further, these agonists appear to enhance aggressive behavior in animals that were not previously defeated, suggesting a modulatory role for CRF type 1 receptors in agonistic behavior that depends on an animal’s previous social experience. Further, localization of CRF receptors was determined in hamster brain in sites thought important for CD and agonistic behavior, but changes in receptor binding following defeat were not observed. Implications of these results and future directions are discussed.
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Cook, Michelle Elizabeth. "Environmental and social factors influence communications used during crayfish agonistic interactions." Bowling Green, Ohio : Bowling Green State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1212431269.
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Mott, Cy Larue. "Biotic and abiotic influences on aggressive interactions within larval Ambystoma assemblages." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/140.
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Coexistence among ecologically similar species is often facilitated through temporal or spatial partitioning mechanisms that reduce or eliminate direct interaction. However, in many communities exhibiting guild structure, wherein potential competitors may also prey on one another, sympatric relationships persist despite species' similar life history strategies, spatial and temporal restrictions imposed by ephemeral habitats, and resource limitations that promote competition and predation. To identify the ecological roles of species-specific behavioral patterns within aquatic guilds, I quantified larval intraspecific agonistic behavior among two species of intraguild (IG) predators, Ambystoma opacum and A. tigrinum, and their shared intraguild prey, A. maculatum. All species exhibited similar ontogenetic patterns of aggression, characterized by peaks of aggression early in development and subsequent gradual decreases through metamorphosis. However, the intensity of aggression varied considerably among guild species through development, as did behavioral responses to varying levels of ambient water temperature, invertebrate prey density, and presence of predatory odonate naiads. The observed patterns suggest that guild species, despite morphological and physiological similarities, exhibit unique behavioral responses through ontogeny and in response to habitat variables, suggesting that temporally staggered breeding phenologies have contributed to behavioral divergence among these sympatric congeners. However, in situ observations of larval behavior, although largely in agreement with laboratory results on timing of increased aggression, indicated that IG predators exhibited pond-level species partitioning and do not necessarily co-occur despite being regarded as sympatric. These results, taken together with observed species-specific impacts of IG predators on IG prey, suggest that ecologically similar IG predators exert widely differing predatory pressure on shared prey, and that similarities among guild species may ultimately result in habitat partitioning across local scales.
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Wofford, Sarah Jane. "Sex and fighting: Male and female crayfish utilize different assessment strategies during agonistic behavior." Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1367768839.
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Druker, Bill B. "Rearing and environmental factors influencing aberrant, affiliative, agonistic and nest-building behaviors in the Alala (Corvus hawaiiensis)." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32990.
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The future of the critically endangered `Alala (Corvus hawaiiensis ), with only seven individuals remaining in the wild, is wholly dependent upon the reproductive success of its captive population. Throughout the 1999 breeding season, behavioral observations were carried out on eight pairs of captive-reared Hawaiian crows. Due to the limited size of the captive population, and to avoid inbreeding, birds were paired based on their genetic profiles. As a result, there were differences in age and breeding experience within pairs. There were also differences in rearing conditions between mates. It has been suggested that social play and other affiliative behaviors may be important in young birds to form normal social bonds later in life. Affiliative behavior, such as allopreening and feeding other, was common among social-reared crows, but was virtually absent in isolate-reared individuals. Conversely, isolate-reared crows displayed various forms of aberrant behavior, including inappropriate play and self-mutilation, significantly more than the social-reared individuals. Since such behaviors occurred in the nest area throughout all phases of the breeding season, namely nest-building, egg-laying and incubation, it would appear as if early rearing condition plays a role in future reproductive success.
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Taylor, Laura. "Sensory Stimuli Involved in Eliciting Agonistic Behavior in the Northern Fence Lizard, Sceloporus Undulatus Hyacinthinus." TopSCHOLAR®, 1988. https://digitalcommons.wku.edu/theses/2914.
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Comparisons among sequence analyses of actions in response to various treatments of visual and olfactory cues were carried out in the lizard, Sceloporus undulatus hyacinthinus, to determine the relative roles of these cues in eliciting agonistic behavior. Visual cues were tested using mirrors, models and clear partitions between cages. Chemical cues were tested using the secretion from the cloaca of males. A combination of visual and olfactory cues was tested by streaking a mirror with the substance from the cloaca of a male. The responses to these treatment conditions were videotaped, and the transition frequencies between the most frequently expressed behaviors (i.e., head turning, crawling, jaw snapping and bobbing) were analyzed according to Chi Square Analysis for Independence. According to these analyses, the transitions occurred in a probabilistic sequence (i.e., the occurrence of one action positively or negatively affected the probability of the occurrence of a particular following action). The patterns of significance in transition frequencies were similar for similar treatment conditions, reenforcing the conclusion that the transition sequences were not occurring at random. Visual cues appeared to play a primary role in eliciting agonistic behavior. Olfactory cues appeared to play a secondary part in agonistic behavior, coming into play only when a visual cue was present first.
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Sibley, Taryn Ann. "Comparison of Agonistic Behaviors by analysis of activity in two groups of Confined Primates, Mandrills (Mandrillus sphinx) and Ring-tailed Lemurs (Lemur catta)." Thesis, Boston College, 2004. http://hdl.handle.net/2345/454.
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Thesis advisor: David Krauss<br>Behavior in a confined group of mandrills (Mandrillus sphinx) and a confined group of ring tailed lemurs (Lemur catta) were analyzed to reveal any significant differences in agonistic behaviors and to assess the varying stress levels between individuals. I predicted that the activity rate of the individuals would determine the amount of agonistic behavior demonstrated, specifically that more active individuals would be more frequently performing agonistic behaviors than those who were less active. The mandrills as a whole exhibited a higher activity rate than the lemurs, and the proportion of time spent exhibiting agonistic behaviors was also higher, as expected. These results suggest that the mandrill population is under more stress than the lemurs. Differences in the age makeup of these groups may partially explain the behavioral differences that occurred: the mandrills' group included a juvenile who was considerably more active than his parents while all three lemurs observed were adults. Differences in the size of the exhibit may also explain the differences as the exhibit for the mandrills was smaller than that of the lemurs, while the mandrills were more than triple the lemurs' size. This analysis supports earlier studies: that primate behavior is influenced strongly by their environment and its cohabitants<br>Thesis (BS) — Boston College, 2004<br>Submitted to: Boston College. College of Arts and Sciences<br>Discipline: Biology<br>Discipline: College Honors Program
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Chabrolles, Laura. "Integrative study of multimodal communication in two models of vertebrates : Maylandia zebra and Crocodylus niloticus." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSES054.
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Bien que l'utilisation de la communication multimodale chez les animaux soit relativement courante, la plupart des études jusqu’à maintenant ont porté sur des systèmes uni- ou bimodaux et n'ont pas examiné comment l’individu qui reçoit les signaux les détectent et les traitent. Cette thèse a pour but d’étudier le système complexe que représente la communication multimodale en conciliant à la fois les interactions qui pourraient exister entre les modalités sensorielles et l'influence potentielle que pourrait avoir l'état physiologique de l’individu recevant les signaux. J'ai utilisé deux espèces de vertébrés comme modèles utilisant des signaux multimodaux : un poisson cichlidé Maylandia zebra, et un crocodile Crocodylus niloticus. Les résultats montrent une interaction entre les différentes modalités, permettant de moduler et d'affiner l'information transmise lors des interactions agonistiques chez Maylandia zebra. Chez les jeunes crocodiles du Nil, l'état prandial (à jeun ou à satiété) est un facteur régulateur important de la motivation qui peut influencer la modulation croisée entre les signaux olfactifs et acoustiques reçus. Cette thèse apporte de nouveaux éléments pour une meilleure compréhension de la communication multimodale chez les vertébrés. Elle appelle à la réalisation d'autres études, empiriques, théoriques et intégratives, sur les systèmes de signalisation multimodale qui devraient aider à comprendre pourquoi la communication animale est devenue si complexe<br>The use of multimodal communication in animals is relatively common, however most of the studies have investigated cues in isolation or in bimodal systems and did not consider how the receivers detect and process signals. This thesis aims to disentangle the complex system of multimodal communication by studying the receiver behavioural responses to unimodal or multimodal stimuli and addressing the potential influence of the receiver physiological state on these responses. I used two vertebrates models that use multimodal signals: a cichlid fish Maylandia zebra, and a crocodile Crocodylus niloticus. The results show an interaction between the different modalities, allowing to modulate and refine the information transmitted during agonistic interactions in Maylandia zebra. In young Nile crocodiles, the prandial state (fasted or sated) is an important regulating factor of motivation which can influence the cross-modulation between olfactory and acoustic inputs. This thesis brings new inputs for a better understanding of multimodal communication in vertebrates. It calls for further studies, empirical, theoretical and integrative, on multimodal signalling systems that should help to clarify why animal communication became so complex
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Furmidge, Lesley Jane. "Effects of partial dopamine D2 agonists on d-amphetamine-induced behaviour." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280506.
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Phillips, Catherine T. Johnston Carol Eileen. "Evolution of signal divergence and behavior in Cyprinella galactura, the whitetail shiner." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Dissertations/PHILLIPS_CATHERINE_27.pdf.
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Solomon, Matia B. "The Effect of Gonadal Hormones on Agonistic Behavior in Previously Defeated Female and Male Syrian Hamsters." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/psych_diss/13.
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Following social defeat, male hamsters exhibit behavioral changes characterized by a breakdown of normal territorial aggression and an increase in submissive/defensive behaviors in the presence of a non-aggressive intruder (NAI). We have termed this phenomenon conditioned defeat (CD). By contrast, only a small subset of defeated females exhibit submissive/defensive behavior in the presence of a NAI. We hypothesized that fluctuations in gonadal hormones might contribute to differences in the display of submissive behavior in intact female hamsters. Following social defeat, proestrous females (higher endogenous estradiol) were more likely to display conditioned defeat compared with diestrous 1 (lower endogenous estradiol) females. This finding suggests that there is an estrous cycle-dependent fluctuation in the display of CD in female hamsters and suggests that increased estradiol might contribute to increased submissive behavior. We then demonstrated that ovariectomized females given estradiol prior to CD testing exhibited significantly higher submissive behavior in the presence of a NAI suggesting that estradiol increases the expression of CD in female hamsters. We have also shown that castrated males that were singly housed for four weeks displayed significantly more submissive behavior than did their intact counterparts. Interestingly, castrated and intact males that were singly housed for 10 days prior to behavioral testing displayed similar behavior during CD testing. Together these data suggest that androgens and isolation modulate the display of CD in male hamsters. Finally, we examined brain activation following CD testing in defeated males and females (in diestrus 1 and proestrus). Defeated male and proestrous females exhibited increased Fos activation in the dorsal lateral septum and hypothalamic paraventricular nucleus relative to defeated diestrous 1 females. Diestrous 1 females exhibited increased Fos expression in the lateral bed nucleus of the stria terminalis compared with both defeated groups. Collectively, these data suggest that gonadal hormones and duration of individual housing modulate the display of CD in female and male hamsters and that those animals which display CD exhibit differences in patterns of neuronal activation than do those that do not display CD.
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GHOSAL, KAUSHIK. "EFFECTS OF AGONISTIC BEHAVIOR AND SOCIAL STATUS ON NEUROGENESIS AND CELL SURVIVAL IN THE CNS OF THE ADULT MALE CRICKET, Acheta domesticus." Miami University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=miami1186668155.
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Sorrell, Mollie R. "A Novel Insect Model To Study The Role Of Fragile X Mental Retardation Protein In Innate Immunity And Behavior." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1564143917001959.
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Voon, V. "Dopamine agonist-induced impulse control behaviors : impulsivity, prediction error and risk." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1323000/.
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A range of pathological behaviours associated with treatment with dopamine receptor agonists (DA) have been reported in Parkinson's disease (PD). The behaviours, known as impulse control disorders (ICD), are linked by repetitive rewarding or motivating choices despite negative consequences and include pathological gambling, compulsive shopping, binge eating and hypersexuality. This patient group provides a model for the study of the effect of both chronic DA and the interaction between DA and vulnerability mediated by cognitive mechanisms. In this thesis, I focus on PD patients with problem gambling, or compulsive shopping behaviors compared to matched PD controls without ICDs and matched healthy volunteers. I begin by outlining the methods used in this study including fMRI, reinforcement learning and model-based fMRI. I then ask whether these behaviours are associated with enhanced learning from gain feedback or impaired learning from loss feedback. As exogenous dopaminergic medications may interfere with the physiological function of phasic dopaminergic activity as a teaching signal, I use a reinforcement learning model to examine the effects of DA and the interaction of DA and vulnerability on prediction error activity as measured in the fMRI. Here, positive reinforcement is simply defined as “any event that increases the probability of a response” and does not imply hedonic value. I show a dissociation as a function of vulnerability: dopamine agonists are associated with faster reward learning in ICD patients and slower loss learning in PD controls. The effects appear to be mediated by differences in striatal prediction error activity. I then examine the effect of DA on various forms of impulsivity including impulsive choice (or the ability to delay gratification) and reaction time with increasing decision difficulty or decision conflict. I show here that DA in ICD patients are associated with greater impulsive choice and more rapid decisions compared to off DA and PD controls. ICD patients overall have faster reaction times compared to PD controls. I also show that ICD patients on DA have worse working memory function compared to PD controls on DA. I then examine the neural correlates of the impulsive choice task in healthy volunteers in an fMRI study. In the final data chapter, I assess the effects of DA on risk taking. I show that DA increases the tendency towards risk taking choices in ICD patients accompanied by a decrease in ventral striatal activity to an index of risk. Thus, DA may lead to an underestimation of risk in ICD patients by decreasing the perception of the difference between the potential for gain and the potential for loss outcomes in the risky choice. Thus, I construct a model of the ICD behavior. In a vulnerable subset of the PD population (presumably reflecting genetic, biological or psychosocial factors), DA hastens learning from rewarding outcomes emphasizing the acquisition phase of these behaviors and DA decreases the estimation of risk. DA appears to increase sensitivity towards immediate rewards over delayed rewards, an effect that may be mediated by the influence of DA on reward magnitude. These cognitive mechanisms can help explain why ICD patients choose to pursue these short term potentially rewarding risky gains despite marked negative financial losses and social and occupational consequences.
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Vilaysinh, Vanhthong. "Sensitization to indirect and direct dopamine agonists, behavioural differences in wheel running." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ65208.pdf.
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Cervo, Luigi. "Cocaine-seeking behaviour by drug-associated stimuli : reversal by dopamine D₃ partial agonists and antagonists." Thesis, Open University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413802.
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Foister, Nicola. "Behavioural phenotyping of mice with genetic alterations of the GABA[subscript A] receptor." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/988.
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GABA is the main inhibitory neurotransmitter of the central nervous system. GABA[subscript A]Rs are multimeric transmembrane receptors, which are composed of 5 subunits. It is known that there are 19 subunits that can make up the GABA[subscript A]Rs, allowing for a vast array of receptor subtypes. In addition to the GABA binding site GABA[subscript A]Rs have distinct allosteric binding sites for benzodiazepines, barbiturates, ethanol, certain general anaesthetics and neuroactive steroids. The molecular heterogeneity of the GABA[subscript A]R is accompanied by distinct pharmacological profiles of the different receptor subtypes. The advance of transgenic mouse models has allowed the functional significance of this heterogeneity to be studied in vivo. Therefore, this thesis utilises a variety of transgenic mouse models carrying either mutations or deletions of certain subunits to study the functional significance of the receptor heterogeneity. Mice lacking the α1 subunit (α1[superscript(-/-)]), carrying a point mutation of the α1 subunit (α1H101R), and mice lacking the δ subunit (δ[superscript(-/-)]) have been utilised to investigate the role of these subunits in the sedative actions of benzodiazepines and the GABA[subscript A]R agonist THIP. Although there are limitations to the interpretation of these results due genetic background of the α1[superscript(-/-)] and α1H101R, experiments suggest that the α1H101R mutation is not behaviourally silent as previously suggested and provide further evidence that the α1 subunit mediates the sedative properties of benzodiazepines. These experiments also reveal that the extrasynaptic δ containing receptors are responsible for mediating the sedative effects of THIP, and these findings combined with evidence from collaborators, implicates the thalamus as an anatomical mediator of these effects. An investigation of the putative cognitive enhancing effects of THIP using an attentional set-shifting task for mice suggested that pre-treatment with THIP reduces the number of errors to reach criterion. δ[superscript(-/-)] mice could not be trained to perform the task, therefore further behavioural investigation of these mice was performed, which suggested a heightened level of anxiety and reduced motivation for a food reward. This thesis has furthered our understanding of the functional role of GABA[subscript A]R subtypes. With the advance in genetic manipulations that allow for regionally selective mutations of the receptor the anatomical structures involved in these functions can be identified.
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Cornelissen, Jeremy. "Pharmacological assessment of adjuncts to enhance mu-opioid receptor agonist antinociception in male rhesus monkeys: Does one + one = three?" VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6115.
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Mu-opioid receptor (MOR) agonists are effective agents for pain management, but are also limited by a number of undesirable effects. One approach to enhance the therapeutic effects and minimize the undesirable effects of MOR agonists may be to combine MOR agonists with an adjunct targeting a different receptor system. This targeted medical approach, known as “combination therapy”, aims to augment the desired effects of the MOR agonist (i.e. antinociception) and/or diminish the undesirable deleterious side effects of the MOR agonist. This dissertation investigated the utility of this approach in an assay of thermal nociception and schedule-controlled responding in male rhesus monkeys with three aims. One aim determined the utility of N-methyl D-aspartate (NMDA) receptor antagonists to selectively enhance MOR agonist antinociception. A second identified the pharmacological determinants of antinociceptive interactions between a nociceptin opioid peptide (NOP) receptor agonist and MOR agonists. A third aim investigated the potential for fixed-proportion mixtures of a competitive MOR antagonist and MOR agonist to manipulate antinociceptive efficacy. Experimental results did not support the utility of NMDA antagonists as adjuncts to selectively enhance MOR agonist antinociception. Furthermore, the antinociceptive interactions between a NOP agonist and MOR agonists were modest and occurred under a narrow range of conditions. Finally, fixed proportion MOR antagonist-agonist mixtures were effective in manipulating antinociceptive in vivo efficacy. In conclusion, this dissertation does not provide strong empirical evidence that a combination therapy approach will result in clinically effective and selective enhancement of MOR agonist analgesia. The dissertation concludes with proposed strategies and novel preclinical methods to enhance preclinical-to-clinical translation of effective candidate analgesics.
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Morgan, Laura. "A Passive Acoustic and Experimental Study of Juvenile Blue Catfish, Ictalurus furcatus, Sound Production and Agnostic Behavior in the Tidal Freshwater James River." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3459.
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Blue catfish, Ictalurus furcatus, are an invasive species in the James River, VA. They produce stridulation sounds and passive acoustic monitoring may prove useful in locating and monitoring their populations. Little is known about their behavior, therefore my goal was to examine agonistic behavior and the use of sound in defending a territory. This thesis consists of two manuscripts: 1) A passive acoustic study of the tidal freshwater James River, 2) An experimental study of agonistic behavior in juvenile Blue catfish, Ictalurus furcatus. The first study showed that three sounds (click, run croak) occurred more often in warmer months than cooler months. The second study showed that Blue catfish utilized a variety of agonistic behaviors in territory defense, with residency status and size having an effect on the type and number of displays used. Stridulation sounds were not present in territorial contests although Blue catfish produce stridulatory pulses when held.
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Freitas, Kelen. "Effects of Nicotinic Acetylcholine Receptor Agonists in Assays of Pain-Stimulated and Pain-Depressed Behavior in Rats." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3999.
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Though a host of analgesics have been developed to alleviate pain, especially acute pain, significant side effects and a lack of long-term efficacy have encouraged research attempts to pursue novel targets that may be associated with fewer side effects or a more sustained efficacy. Among these new targets are members of the nicotinic family of acetylcholine receptors (nAChRs). The non-selective nAChR agonists nicotine and epibatidine have been shown to function as potent antinociceptive drugs in many acute and chronic preclinical pain models, while nicotine has produced analgesic effects in humans. However, these non-selective nAChRs agonists also produce various side effects, including gastrointestinal and cardiovascular complications that limit clinical utility. To reduce these side effects, recent research has focused on evaluating the potential role of specific nAChR subtypes in the modulation of nociception. Traditionally, assays of pain-stimulated behaviors, or behaviors that increase in rate, frequency or intensity after presentation of a noxious stimulus, have been used to evaluate nAChR agonists and other classes of candidate analgesics pre-clinically. However, clinically relevant pain states are often associated with the depression of behavior; for example in humans, pain is often accompanied by impaired function in daily activities and depression of mood. To address these depressant manifestations of pain, novel preclinical assays have been developed to assess the expression and pharmacological modulation of pain-depressed behaviors, or behaviors that decrease in rate, frequency or intensity after presentation of a noxious stimulus. Additionally, the effects of nAChR agonists in preclinical assays of pain-depressed behavior are unknown. In assays of pain-stimulated behavior, agonism of α4β2* receptors appears to play a prominent role in antinociception produced by drugs that target nAChRs. Recent research suggests that α7 nAChR subtype might be an alternative target. Accordingly, the primary goal of this dissertation was to compare antinociceptive effects of the nAChR agonist nicotine and more selective nicotinic agonists in assays of pain-stimulated and pain-depressed behavior. Results from this body of work show that both nicotine and the more selective α4β2* agonist 5-I-A-85380 produced antinociception in both types of assays, whereas an α7 agonist did not. Taken together, these results suggest that α4β2* nAChR agonists may be especially effective to treat signs of pain-related behavioral depression; however nonselective behavioral effects of these compounds may contribute to apparent antinociception. Studies of nAChR agonist effects on pain-depressed behavior were conducted using an assay of intracranial self-stimulation (ICSS) as a baseline behavior that is depressed by noxious pain stimuli, and pain-related depression of ICSS can be selectively alleviated by clinically effective analgesics. As a prelude to studies of nAChR agonist effects on pain-related depression of ICSS, a preliminary study was conducted to assess effects of nicotine and 5-I-A-85380 on ICSS in the absence of a noxious stimulus. These studies indicated that selective α4β2* agonists may have higher abuse potential than nicotine. Additionally, cognitive function is one domain of behavior that may be impaired by pain, and nAChR agonists are used to treat cognitive impairment produced by other non-pain pathologies. Accordingly, a final goal of this project was to develop an assay of pain-related cognitive impairment in rats that could be used to evaluate effects of nAChR agonists. Although results of this study did provide evidence for pain-related impairment of cognition, the effects of the pain stimuli were sufficiently variable and transient to make this procedure impracticable for use in studies with nAChR agonists.
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Schneider, Stephanie Michelle Romy. "Love, hatred and indifference in chimpanzees: Personality, Subjective Well-Being, and dyadic-level behavior in captive chimpanzees (Pan troglodytes): Does something more than rank, age and sex drive the nature of interpersonal relationships in chimpanzees?" Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/325003.
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This dissertation consists of two studies: the first focuses on reliability of chimpanzee personality and subjective well-being (SWB) scores, the second on validating those scores by comparing them to subjective assessments of behavior in dyads. The first measured reliability of scores of personality and subjective well-being (SWB) across ten years. Dominance rank, and the Dominance and Extraversion Factors significantly correlated between time points. In the second study, I investigated the impact of personality, SWB, and demographic characteristics on individual variation in dyadic-level individual behavior. Age predicted likeability in females, and age and rank predicted likeability in males. Neither personality factors nor SWB were correlated to likeability. An Affable domain scale and an Agonistic domain scale were constructed from the personality items. The Affable domain scale correlated with chimpanzees who were scored high neutral in social interactions, and the agonistic scale correlated with low neutral score in social interactions.
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Taylor, Stacie Lin. "Neurocircuitry and Molecular Basis of Conditioned Defeat in Male Syrian Hamsters." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/psych_diss/40.
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Stress affects virtually all organisms and can result in both physiological and behavioral changes. Conditioned defeat in Syrian hamsters is a model of stress-induced behavioral plasticity that occurs in a social context. In this model, hamsters are defeated by a larger, more aggressive counterpart. Defeated hamsters subsequently fail to defend their own territory and show striking and long-lasting increases in submissive behavior even when paired with a non-threatening counterpart. The present series of experiments seeks to identify the brain regions and molecular mediators that contribute to this behavioral plasticity. One brain region that has been overlooked by our laboratory is the hippocampus. The results of the first study suggested that the ventral, but not dorsal, hippocampus is important for the acquisition of conditioned defeat as temporary inactivation of the ventral hippocampus prior to defeat training significantly reduced submissive and defensive behaviors when hamsters were tested with a non-aggressive intruder. Next, we sought to identify a potential molecular mediator of social stress-induced behavioral plasticity in hamsters identified as winners or losers after a fight. Using in situ hybridization for brain-derived neurotrophic factor (BDNF) mRNA, we showed that winning and losing hamsters exhibited differences in BDNF mRNA in several regions including the basolateral and medial amygdala as well as the dentate gyrus of the dorsal hippocampus and CA1 of the ventral hippocampus. We next showed that neurotrophic activity in the basolateral amygdala is important for the acquisition of conditioned defeat because K252a infused into the basolateral amygdala prior to defeat training by an aggressive counterpart, significantly decreased submissive and defensive behavior during subsequent testing. Finally, existing data suggest that the amygdala and hippocampus interact to modulate the formation of emotional memories. To test the hypothesis that the basolateral amygdala and ventral hippocampus interact to mediate the behavioral plasticity observed in conditioned defeat, we simultaneously inactivated these regions either contralaterally or ipsilaterally prior to social defeat. Our results suggest that BLA and VHPC interact to mediate the acquisition of conditioned defeat, however, the nature of this interaction remains to be determined.
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Ochalek, Taylor Anne. "Examining sucrose subjective response among individuals with opioid use disorder." ScholarWorks @ UVM, 2020. https://scholarworks.uvm.edu/graddis/1185.
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Aims: Opioid use disorder (OUD) is associated with significant morbidity and mortality, and opioid agonist treatment (OAT) with methadone or buprenorphine represents the most efficacious treatment. However, data suggest that chronic administration of opioids may be associated with significant weight gain, possibly by altering an organism’s perception of and preference for sweet foods. The primary aim of this laboratory study was to rigorously examine sucrose subjective response among adults receiving OAT and a comparison sample without OUD. As secondary outcomes, we also sought to compare the groups on additional baseline characteristics that may influence subjective sucrose response and weight gain during treatment.
Methods: Participants were 40 adults receiving treatment for OUD (OUD+) and a comparison sample of 40 adults without OUD (OUD-). All participants completed an initial screening visit that included questionnaires on eating behaviors, diet and nutrition, recent substance use, and measurement of body mass index. Eligible participants completed two, same-day outpatient laboratory sessions during which they sampled six experimenter-administered concentrations of sucrose solution (0, 0.1, 0.25, 0.5, 0.75, and 1.0M in distilled water) each three times under double-blind counterbalanced conditions. Following each exposure, participants rated the pleasantness and intensity of each sample using 100-point visual analog scales.
Results: OUD+ participants rated sucrose solutions as less pleasant than OUD- participants (p<0.001). However, this effect was limited to the three lowest sucrose concentrations (0, 0.1, 0.25M), and at higher concentrations there were no group differences. There were no between-group differences on ratings of intensity (p=0.35). Given these baseline group differences in placebo (0M) responding, sucrose response was also examined in terms of change from baseline. In this analysis, there was a significant group effect, with a higher magnitude of change in pleasantness ratings and a lower magnitude of change in intensity ratings from 0M in OUD+ vs. OUD- participants (p’s<0.05). With regard to baseline characteristics that may influence sucrose response and eating behavior more generally, the OUD+ group had a higher prevalence of obesity, food insecurity, unhealthy eating behaviors, high sugar consumption, and nutrition knowledge deficits compared to the OUD- group (p’s<0.05).
Conclusion: Data from preclinical and clinical research have suggested that opioid agonist medications may enhance subjective response to sweet flavors. In the present study, OUD+ participants exhibited a higher magnitude of change in pleasantness ratings from placebo compared to OUD- participants. However, this effect was largely driven by pronounced group differences in perceived pleasantness of essentially unsweet solutions. On the outcome of sucrose intensity, findings were more mixed with no consistent differences between OUD+ and OUD- participants. In contrast, group differences were far more pronounced in participants’ daily eating behaviors and nutrition knowledge, with OUD+ participants presenting with a consistently more severe profile. These data highlight the significant risk factors experienced by OUD+ individuals that extend beyond drug-related risks and may inform future scientific and clinical efforts to improve health outcomes in this vulnerable population.
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Maratos, Eleni Chryssa. "Behavioural and biochemical investigations into dyskinesia by levodopa or dopamine agonists in the MPTP-treated common marmoset." Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271323.
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Kienzle, Frederike Bianca. "Die Wirkung des 5-HT 1A-Agonisten 8-OH-DPAT auf die Serotoninfreisetzung im lateralen Hypothalamus und des Fressverhalten der Ratte." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2002. http://dx.doi.org/10.18452/14982.
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Serotonin (5-HT) nimmt eine wichtige Rolle in der Regulation von Nahrungsaufnahme ein. Erhöhte 5-HT-Freisetzung hemmt die Nahrungsaufnahme. Der 5-HT1A-Rezeptor liegt sowohl somatodendritisch als auch postsynaptisch vor. Seine Stimulation mit 8-OH-DPAT vermindert die 5-HT-Freisetzung. Die in-vivo-Mikrodialyse ermöglichte uns eine kontinuierliche Messung von extrazellulärem 5-HT im lateralen Hypothalamus an der frei beweglichen Ratte. Unsere Ergebnisse zeigen einen Abfall der 5-HT-Freisetzung bei satten Ratten, nicht jedoch wenn diesen nach Substanzgabe Futter angeboten wurde. Bei hungrigen Ratten war nach Substanzgabe keine signifikante Veränderung in der 5-HT-Freisetzung zu messen. Zusammenfassend wird mit der vorliegenden Studie erstmals die Wirkung von 8-OH-DPAT auf die 5-HT-Freisetzung im LHA in Abhängigkeit von unterschiedlichen Motivationszuständen in Verbindung mit Nahrungsaufnahme gezeigt.<br>Serotonin (5-HT) is an important mediator of satiety. Increase of 5-HT release inhibits food intake. 8-OH-DPAT, an agonist at the somatodendritic 5-HT1A autoreceptor, reduces serotonergic activity and induces food intake. With the technique of in vivo microdialysis we were able to measure continuously extracellular 5-HT in the lateral hypothalamic area (LHA) in freely moving rats under different feeding conditions. The present results show a decrease of 5-HT release in freely feeding rats after administration of 8-OH-DPAT. This effect was not obtained when offering food after drug application. In contrast, no significant effect in 5-HT release after application of 8-OH-DPAT in food deprived rats was measured. In summery this study demonstrates the effect of 8-OH-DPAT on the 5-HT release in LHA of freely moving rat depending on the different feeding conditions.
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MCKEE, ROBERTA LYNN. "THE DIFFERENTIAL BEHAVIOR OF GLUCAGON AGONISTS AND ANTAGONISTS ON NORMAL AND DIABETIC LIVER: EVIDENCE FOR CYCLIC-AMP - INDEPENDENT EVENTS." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184083.
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A nonrecirculatory liver slice perifusion system has been developed and utilized for investigating glucagon-stimulated glycogenolysis in normal and diabetic states. It has been shown here that slices maintained in this system experience a controlled environment with respect to temperature and pH and remain viable throughout a three-hour experimental period based upon their maintenance of intracellular potassium levels. Although glycogen content falls by 40%, slices exhibit significant glycogenolysis in a dose-response manner upon challenge with glucagon, with maximal concentrations eliciting a 2.2-fold stimulation. This system, which permits nonrecirculatory challenge of liver tissue and subsequent analysis of both intracellular events and overall physiological responses, is extremely useful for examining hormonal mechanisms operating for glucagon, particularly at low concentrations. Using this methodology, liver slices challenged with glucagon exhibit a biphasic dose-response for glycogenolysis. While the second phase parallels cAMP (cyclic adenosine 3':5'-monophosphate) accumulation and cAMP-PK (cAMP-dependent protein kinase) activation, the first is mediated independent of cAMP. Trinitrophenylhistidine-1, homoarginine-12-glucagon (THG), which can antagonize glucagon-stimulated adenylate cyclase, exhibits 50% partial agonist activity for cAMP production and cAMP-PK but full agonism for glycogenolysis. Separation between these events is only two-fold indicating a cAMP-mediated process. [Des-amino-fYRKKE]-glucagon, ([Des-amino-His¹,D-Phe⁴,Tyr⁵,Arg¹²,Lys¹⁷·¹⁸,Glu²¹]-glucagon), another adenylate cyclase antagonist, does not stimulate cAMP or cAMP-PK up to 25 μM yet still elicits glycogenolysis. These results demonstrate that glucagon does indeed stimulate both cAMP-independent as well as cAMP-dependent glycogenolysis in normal liver. In diabetic systems, glucagon elicits attenuated adenylate cyclase activity in liver plasma membranes with reduction in basal activity and extent of stimulation. Maximal stimulation of cAMP production is also reduced by half in liver slices, but in both systems (normal vs. diabetic) EC₅₀ values for cAMP production are identical. Neither THG nor [des-amino-fYRKKE]-glucagon stimulate cAMP production or cAMP-PK in diabetic liver slices. While THG lowers blood glucose levels in vivo, [des-amino-fYRKKE]-glucagon acts as an agonist. These results suggest that the mechanisms which operate for glucagon-stimulated glycogenolysis in normal liver are attenuated in the diabetic state. Furthermore, antagonism of cAMP production alone is insufficient to antagonize glucagon's overall physiological action.
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Habteab, Biniyam Seged. "Implant of a Selective Estrogen Receptor Alpha Agonist to the Male Rat Medial Preoptic Area Maintains Mating Behavior." Digital Archive @ GSU, 2007. http://digitalarchive.gsu.edu/biology_theses/9.
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ABSTRACT Evidence from knockout studies in male mice and from experiments in male rats,in which expression of the estrogen receptor alpha (ERα) gene was inhibited in the medial preoptic area (MPO), suggests that ERα is important in the control of male rat mating behavior. Therefore, in this experiment, we tested the hypothesis that activation of ERα in the MPO is sufficient to maintain mating behavior in castrated male rats receiving subcutaneously (s.c.) dihydrotestosterone (DHT), a non-aromatizable androgen. Accordingly, castrated rats treated with DHT s.c. received MPO implants of either: (i) propyl-pyrazole-triol (PPT) (Stauffer, et al 2000; Katzenellenbogen, et al 2000), a selective ERα agonist, (ii) E2 (positive controls) or (iii) cholesterol (negative controls)and sexual behavior was monitored. PPT was as effective as E2 at maintaining mating behavior suggesting that, in the MPO, ERα is sufficient to mediate responses to E2 that underlie male rat mating behavior.
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Duke, Marcus Alan. "The effects of kappa opioid and dopamine agonists on unconditioned behaviors and fos immunoreactivity in preweanling and adult rats." CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/1209.
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Tremblay, Mélanie. "Neurobiological and behavioural effects of chronic administration of the D₂/₃ agonist ropinirole in relation to iatrogenic gambling disorder." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/63360.
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Neurobiological changes in Parkinson’s Disease (PD) involve dramatic loss of dopamine neurons in the substantia nigra (SNc) and terminals in the dorsal striatum. L-DOPA, first line treatment for PD, can produce debilitating side-effects like dyskinesia over time. Preferential dopamine D2/3 agonists like ropinirole, are used to treat PD, but these newer drugs can lead to impulse control disorders (ICDs) and gambling disorder in a significant minority of patients. The mechanism mitigating dopamine replacement therapy (DRT)-induced ICDs, or whether premorbid behavioural tendencies are a risk factor are unknown. We show that chronic ropinirole increases preference for uncertainty on the rodent Betting task (rBT), regardless of animals’ baseline preference for the safe or uncertain option. Comparatively, ropinirole had subtle effects on choice of a cued version of the rat Gambling task (rGT), while increasing impulsivity, suggesting different neural mechanisms in performance of these tasks. GSK3ß has been involved in disorders of impulsivity suggesting a potential intracellular mechanism for DRT-ICDs. However, chronic administration of SB 216763, a GSK3ß inhibitor, did not attenuate gambling-like behaviours following ropinirole, but also did not reliably decrease GSK3ß levels, such that we were unable to unequivocally determine its role in ropinirole-induced preference for uncertainty. The “overdose” hypothesis, in which DRTs would replenish dopamine stores in the deteriorated dorsal striatum and improve movement, but overwhelm the mostly spared mesolimbic reward system, was suggested to explain DRT-ICDs in PD. However, newer studies suggest a potential involvement for the nigrostriatal, rather than mesolimbic, pathway in gambling disorders. We therefore manipulated the nigrostriatal pathway using designer receptors exclusively activated by designer drugs (DREADDs). Activation of dopamine neurons in the SNc increased preference for uncertainty on the rBT in wager-sensitive rats, partially mimicking the effect of ropinirole, while inhibition of these neurons had no effect on the increase in preference for uncertainty caused by ropinirole. These studies suggest a potential role for activation of the nigrostriatal pathway in DRT-ICDs. They also suggest that ICDs result from DRT alone, rather than from an interaction between medication and basal risk preference, or change in dopamine function caused by the diseases for which they are prescribed.<br>Arts, Faculty of<br>Psychology, Department of<br>Graduate
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Souza, Vinicius Carvalho da Silva e. "Comportamento territorial de Hylodes nasus em um riacho na Floresta da Tijuca, Rio de Janeiro." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2785.
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O comportamento territorial é exibido por animais que competem por recursos dentro de uma área específica defendida. Ao excluir competidores potenciais desta área através de comportamentos agressivos, os indivíduos territoriais garantem acesso prioritário aos recursos essenciais para sua sobrevivência e reprodução. Em anfíbios anuros, a territorialidade tem sido relacionada principalmente com espécies de reprodução prolongada, cujos sítios reprodutivos estão disponíveis durante todo o ano. O presente trabalho foi realizado em um trecho de riacho na Floresta da Tijuca, Rio de Janeiro. Foram realizadas quatro visitas consecutivas a área de amostragem em cada mês (abril/2009 à agosto/2010). O objetivo foi responder questões sobre a territorialidade dos indivíduos da espécie Hylodes nasus: (área de vida, fidelidade ao sítio, comportamentos agonísticos e combates físicos). As áreas de vida dos machos apresentaram relação significativa com o número de recapturas. O tamanho da área de vida das fêmeas foi ligeiramente maior do que dos machos. Os machos apresentaram maior fidelidade do que as fêmeas. A fidelidade apresentou resultado significativo com o CRC e a massa corporal dos indivíduos. Foram observadas 50 interações agonísticas entre machos, sendo exibidos 11 comportamentos agressivos. Foram observados 19 combates físicos, sendo os machos envolvidos classificados como residente, intruso, vencedor ou perdedor. Todas as disputas foram vencidas por indivíduos residentes. Informações a respeito da influência de fatores ambientais sobre a população de H. nasus, aspectos da estrutura populacional e descrição do microhábitat também são fornecidos.<br>The territorial behavior is exhibited by animals that compete for resources within a specific defended area. By excluding potential competitors in this area through aggressive behavior, territorialist individuals ensure priority access to essential resources for their survival and reproduction. In anuran amphibians, territoriality has been mainly related to prolonged-breeding species, whose breeding sites are available throughout the year. This study was conducted in a portion of the river in the Tijuca Forest, Rio de Janeiro. There were four consecutive visits to the sampling area in each month (April/2009 to August/2010). The objective was to answer questions about the territorial behavior of Hylodes nasus (home range, site fidelity, agonistic behaviors and physical fighting). The males home range showed a significant relation with number of recapture. The home range estimated for females was slightly larger than males. Males have higher site fidelity than females. The site fidelity showed a significant relation with individuals' SVL and body mass. There were observed 50 agonistic encounters between males, showing 11 aggressive behaviors. There were observed 19 physical fights with males being classified as resident, intruder, winner or loser. All contests were won by resident individuals. Information about the influence of environmental factors on the population of H. nasus, aspects of population structure and description of microhabitat are also provided.
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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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Previous issue date: 2009-12-04<br>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.<br>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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Shabani, Shkelzen. "The Role of Chemical Senses in Predation, Risk Assessment, and Social Behavior of Spiny Lobsters." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/biology_diss/44.
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Chemical senses play a critical role in predator-prey and social interactions of many animals. Predators often evoke adaptive escape responses by prey, one of which is the release of chemicals that induce adaptive avoidance behaviors from both predators and conspecifics. I explore the use of chemicals in predator-prey and social interactions, using a crustacean model system, the spiny lobster. As predators, spiny lobsters are opportunistic, polyphagous feeders, and they rely heavily on their chemical senses during feeding. Some of their potential prey deter attacks through chemical defenses that act through the spiny lobsters’ chemical senses. An example of this is sea hares, Aplysia californica, which secrete an ink when vigorously attacked by sympatric spiny lobsters, Panulirus interruptus. I show that that this ink defends sea hares from spiny lobsters through several mechanisms that include phagomimicry, sensory disruption, and deterrence, and that the ink’s efficacy is enhanced by its naturally high acidity. As prey, spiny lobsters rely heavily on their chemical senses to assess risk from predators. One way to assess risk of predation is through ‘alarm cues’, which are injury-related chemicals. I show that injured Caribbean spiny lobsters, Panulirus argus, release alarm cues in their hemolymph, and that nearby conspecifics detect these cues using olfaction. Hemolymph from conspecifics induces primarily alarm behavior in the form of retreat, sheltering, and suppression of appetitive responses. In contrast, hemolymph from heterospecifics, depending on phylogenetic relatedness, induces either mixed alarm and appetitive behaviors or primarily appetitive behaviors. Spiny lobsters also use chemical cues to assess risk during social interactions with conspecific. I show that spiny lobsters use urine-borne chemical signals and agonistic behaviors to communicate social status and that these chemical signals are detected exclusively by the olfactory pathway. Dominant animals increase urine release during social interactions, whereas subordinates do not. Experimental prevention of urine release during interactions causes an increase in agonism, but this increase is abolished when urine of dominants is reintroduced. My findings lay the foundation for neuroethological studies of risk-assessment systems mediated by intraspecific chemical cues.
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Teixeira, Odilene de Souza. "TERMINAÇÃO DE BOVINOS AOS 18 MESES COM DIFERENTES CONDIÇÕES SEXUAIS SUPLEMENTADOS EM PASTAGEM DE ARUANA." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/10917.
Full textAbstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>This study aimed to evaluate performance, behavior as well as meat and carcass characteristics of beef cattle with different sexual conditions, finished at 18 months, raised on Aruana (Panicum maximum Jacq cv. Aruana) pasture, receiving energy supplementation. The treatments consisted of surgically castrated, immunocastrated or non-castrated animals. The experiment consisted of 39 contemporary male bovine animals with initial body weight of 284.1 ± 31.4 kg and average age of 14 months. Chemical composition analysis and patterns of pasture production did not differ among treatments. Average daily gain, final weight and live weight gain per hectare, were not influenced by the sexual condition. In assessing the agonistic behavior of the animals, non-castrated animals more often displayed aggressive activities such as threats and fights when compared to immunocastrated animals. Feeding behavior, grazing time, rumination and idleness were not affected by treatments. Non-castrated animals spent more time at the feeder (56.20 minutes) than either surgically castrated (41.43 minutes) or immunocastrated, (32.38 minutes).. As for carcass attributes, no difference was found for slaughter weight, hot and cold carcass weight and their respective yields. Regarding Muscle and fat yield per 100 kg of cold casting, non-castrated animals had higher muscle ratio (67.9%) vs. castrated calves (65.1%) or immunocastrated (64,1%) in detriment of the greater proportion of fat found in castrated animals. Regarding meat characteristics, meat from immunocastrated and surgically castrated animals demonstrated color with greater intensity of red and yellow hues. The characteristics evaluated by the taste panel did not differ for any of the evaluated sexual conditions and were classified as "slightly above average". The combination of the correct handling of Aruana grazing and the use of supplementation was promising for finishing cattle with different sexual conditions at 18 months of age, considering that there was no difference in average daily gain, final weight and gain liveweight per hectare. Castrates both surgically as immunocastrated obtained higher yield of fat in the carcass while uncastrated animals have higher muscle performance. In the flesh, there was difference in the color, and steers (surgically or immunocastrated) produced meat prone to lighter red color compared to uncastrated cattle. In choosing the method recommended castration this latter, to be a less invasive method for cattle, which determines greater preservation of animal welfare.<br>Objetivou-se, mensurar o desempenho, o comportamento e as características de carcaça e carne de bovinos de corte com diferentes condições sexuais, terminados aos 18 meses em pastagem de Aruana, recebendo suplementação energética. Os tratamentos consistiram em novilhos castrados cirurgicamente, imunocastrados ou não castrados. Foram utilizados, para o experimento, 39 bovinos machos, contemporâneos, com peso corporal e idade inicial média de 284,1 ± 31,4 kg e 14 meses, respectivamente. Os resultados referentes à análise da composição bromatológica e os parâmetros produtivos da pastagem não diferiram para os tratamentos. As variáveis, ganho médio diário, peso final e ganho de peso vivo por hectare, não sofreram influência da condição sexual. Ao avaliar o comportamento agonístico dos novilhos verifica-se que os não castrados apresentaram maior número de atividades como ameaças e brigas em relação aos imunocastrados. No comportamento ingestivo, os tempos de pastejo, ócio e ruminação não foram influenciados pelos tratamentos. O tempo de permanência no comedouro dos animais não castrados, 56,20 minutos, foi superior ao detectado para castrados cirurgicamente ou imunocastrados, 41,43 e 32,38 minutos. Nos atributos de carcaça, não foi encontrada diferença para peso de abate, peso de carcaça quente e fria, bem como para seus respectivos rendimentos. No que se refere aos rendimentos de músculo e gordura por 100 kg de carcaça fria, os novilhos não castrados obtiveram maior proporção de músculo (67,9%) ao comparar com novilhos castrados cirurgicamente (65,1%) ou imunocastrados (64,1%), em detrimento da maior proporção de gordura dos animais castrados. Para as características de carne, os novilhos castrados cirurgicamente e imunocastrados dispuseram de carnes com maior intensidade de vermelho e amarelo. As características avaliadas pelo painel de degustadores não diferiram para nenhuma das condições sexuais trabalhadas neste ensaio, sendo classificadas como levemente acima da média . A combinação entre o correto manejo da pastagem de Aruana e o uso de suplementação se mostrou promissora para a terminação de bovinos com diferentes condições sexuais aos 18 meses de idade, considerando-se que não houve diferença para ganho médio diário, peso final e ganho de peso vivo por hectare. Animais castrados tanto cirurgicamente quanto imunocastrados obtiveram maior rendimento de gordura na carcaça, enquanto, animais não castrados apresentam maior rendimento de músculo. Na carne, observou-se diferença para a cor, sendo que novilhos castrados (cirurgicamente ou imunocastrados) produziram carne com tendência a coloração vermelho mais claro, comparado aos bovinos não castrados. Na escolha do método de castração se recomenda essa última, por ser um método menos invasivo para o bovino, o que determina maior preservação do bem- estar animal.
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Rodrigues, Laís Silva. "Abundância e ecologia reprodutiva de Abudefduf saxatilis (Linnaues, 1758) (Osteichthyes:Pomacentridae) no arquipélago de São Pedro e São Paulo, Brasil." Universidade Federal da Paraíba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/4141.
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Previous issue date: 2013-03-15<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>The abundance and ecological attributes, as behavior and reproduction, of reef fishes are usually
influenced by variations in habitat structure, e.g. benthic cover and structural complexity. The
preference for different habitats generally varies according to the ontogenetic stage, with juveniles
generally concentrated in shallow waters and adults in deeper and away from the coast areas.
Abudefduf saxatilis, the sergeant-major (Pomacentridae) is a reef fish widely distributed in coastal
and oceanic reef habitats in the West Atlantic. In the small and remote St. Peter and St. Paul s
Archipelago (SPSPA), located on the Mid Atlantic Ridge, the sergeant-major is one of the most
abundant reef fish species. The sergeant-major population of the SPSPA is morphologically and
genetically distinct from other populations in West Atlantic, suggesting low genetic connectivity
and self-maintenance by local reproduction. The main objectives of this study are: 1) to describe the
abundance and spatial distribution of the sergeant-majors from SPSPA (tidal pools and the islands
inlet) and 2) to quantitatively characterize the reproductive ecology aspects of the species on site.
Data on fish and nest abundance were collected using a stationary visual census methodology.
Benthic complexity was measured using a rolling stick, at the inlet and the chain link method on
tide pools. Benthic cover was estimated using photo-quadrats. Data on the reproductive behavior of
male guardians and the nests individual monitoring were collected by the focal animal method and
photographs, respectively. The smaller sergeant-majors representatives (<2 cm in total length, TL)
were recorded exclusively in the tidal pools, predator-free environments that have been identified as
potential nurseries for this species in the SPSPA. No significant influences were recorded on the
complexity of the substrate in the abundance and distribution of sergeant-majors in tidal pools and
little or no influence of benthic coverage. In the inlet, there was a positive relationship between A.
saxatilis body size and depth, with individuals sized between 2-10 cm CT concentrated on
shallower strata (0-10 m depth). Individuals among 10-20 cm CT switch to occupy depths below 10
m and suffered significant influence of complexity, suggesting greater need of refuge from
predators. The density of A. saxatilis nests was lower in areas with higher abundance of Stegastes
sanctipauli, a territorial Pomacentridae, abundant in the archipelago, suggesting possible negative
interactions as competition for territory and optimal nesting sites. Places with higher densities of
nests of A. saxatilis also had higher densities of the eggs' predator Halichoeres radiatus, suggesting
aggregation of this predator in areas with a greater supply of eggs. The agonistic interactions
between male guardian and nests invaders were more frequent in less accessible nests, probably due
to greater difficulty on detecting intruders in these nests. Factors that negatively influenced the
spawning success, i.e. proportion of eggs remaining over time, were the total agonistic interactions
between males and invaders, total bites by male guardian in their own nest and guardian male's size.
Depth was the only factor that positively influenced the spawning success. These last results
suggest that larger males probably defend spawning that is more attractive to egg's predators and
egg predation significantly influences the spawning success of A. saxatilis in SPSPA. Furthermore,
if the male spends more time in nest defense, the chances of foraging in areas distant from the nest
are smaller, being one of the most plausible explanations for the significant influence of filial
cannibalism in spawning success. The higher reproductive success at greater depths may be related
to the absence of competition with other abundant territorial damsels species that spawn in shallow
areas from SPSPA, specially Stegastes sanctipauli and Chromis multilineata.<br>A abundância e atributos ecológicos, como comportamento e reprodução, de peixes recifais são
geralmente influenciados por variações na estrutura do habitat, tais como cobertura bentônica e
complexidade estrutural. A preferência por diferentes habitats pode variar ontogeneticamente, com
jovens geralmente concentrados em áreas rasas e adultos em áreas mais fundas e afastadas da costa.
Abudefduf saxatilis, o sargentinho (Pomacentridae) é um peixe recifal amplamente distribuído em
ambientes costeiros e insulares no Atlântico Ocidental. No pequeno e remoto Arquipélago de São
Pedro e São Paulo (ASPSP), localizado sobre a Dorsal Meso-Atlântica, o sargentinho é uma das
espécies de peixes recifais mais abundantes. A população de sargentinhos do ASPSP é morfológica
e geneticamente distinta das demais populações no Atlântico Ocidental, sugerindo baixa
conectividade genética e automanutenção através da reprodução local. Os objetivos principais deste
estudo são: 1) descrever a abundância e distribuição espacial de sargentinhos no ASPSP (piscinas
de maré e enseada do arquipélago) e 2) caracterizar quantitativamente aspectos da ecologia
reprodutiva da espécie no local. Dados sobre abundância de sargentinhos e de ninhos foram
coletados através de censos visuais estacionários. A complexidade do substrato foi avaliada através
da metodologia do bastão, na enseada, e método da corrente nas piscinas de maré. A cobertura
bentônica nas piscinas de maré foi caracterizada utilizando-se foto-quadrados. Dados sobre o
comportamento reprodutivo de machos guardiões o e monitoramento de desovas em ninhos
individuais foram coletados pelo método do animal focal e fotografias, respectivamente. Os
menores representantes de sargentinhos (< 2 cm de comprimento total, CT) foram registrados
exclusivamente nas piscinas de maré, ambientes livres de predadores que foram identificados como
potenciais berçários para esta espécie no ASPSP. Não foi registrada influência significativa da
complexidade do substrato na abundância e distribuição de sargentinhos nas piscinas de maré e
pouca ou nenhuma influência da cobertura bentônica. Na enseada, foi registrada uma relação
positiva entre profundidade e tamanho de corpo de A. saxatilis, com indivíduos entre 2-10 cm CT
concentrados na faixa mais rasa (0-10 m de profundidade). Indivíduos entre 10-20 cm CT passaram
a ocupar profundidades abaixo de 10 m e sofreram influência significativa da complexidade,
sugerindo maior necessidade de refúgio contra predadores. A densidade de ninhos de A. saxatilis foi
menor em locais com maior abundância de Stegastes sanctipauli, um pomacentrídeo territorial
abundante no ASPSP, sugerindo possíveis interações negativas, como disputa por território e locais
ótimos de nidificação. Locais com maiores densidades de ninhos de A. saxatilis também
apresentaram maiores densidades do predador de ovos Halichoeres radiatus, sugerindo agregação
deste predador em áreas com maior oferta de ovos. As interações agonísticas entre o macho
guardião e invasores de ninhos foram mais frequentes em ninhos menos acessíveis, provavelmente
devido a maior dificuldade em detectar invasores nestes ninhos. Os fatores que influenciaram
negativamente o sucesso da desova, ou seja, proporção de ovos remanescentes ao longo do tempo,
foram o total de interações agonísticas entre machos e invasores, o total de mordidas do macho
guardião no próprio ninho e o tamanho do macho guardião. A profundidade foi o único fator que
influenciou positivamente o sucesso da desova. Estes últimos resultados sugerem que machos
maiores defendem desovas mais atrativas aos predadores de ovos e a predação de ovos influencia
significativamente o sucesso de desova de A. saxatilis no ASPSP. Além disso, se o macho despende
mais tempo na defesa do ninho, as chances de forragear em áreas distantes do ninho são menores,
uma explicação plausível para a influência significativa do canibalismo filial no sucesso da desova.
O maior sucesso reprodutivo em profundidades maiores pode estar relacionado à ausência de
competição com outras espécies abundantes de donzelas territoriais que desovam em áreas rasas do
ASPSP, principalmente Stegastes sanctipauli e Chromis multilineata.
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Brown, Russell W., Marla K. Perna, Tori L. Schaefer, and Michael T. Williams. "The Effects of Adulthood Nicotine Treatment on D2-Mediated Behavior and Neurotrophins of Rats Neonatally Treated with Quinpirole." Digital Commons @ East Tennessee State University, 2006. https://doi.org/10.1002/syn.20237.
Full textAbstract:
This study was designed to analyze the effects of nicotine on yawning behavior and neurotrophin content in the hippocampus and frontal cortex of D2-receptor primed female adult Sprague-Dawley rats. Animals were neonatally treated with quinpirole, a dopamine (DA) D2/D3 agonist, from postnatal day 1-21 (P1-21) and raised to P60 and administered nicotine tartarate (0.3 mg/kg free base) or saline twice daily for 14 days. One day after nicotine treatment had ceased, the number of yawns was recorded for 1 h in response to an acute injection of quinpirole (i.p., 100 microg/kg). Yawning is a D2-receptor mediated event. D2-primed rats demonstrated a significant increase in yawning in response to acute quinpirole compared with that of controls, but nicotine did not alleviate this effect. Neonatal quinpirole treatment produced a significant decrease of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in the hippocampus that was alleviated by adulthood nicotine treatment. Interestingly, nicotine treatment to controls produced a significant increase of NGF in the frontal cortex, but a significant decrease of both NGF and BDNF in the hippocampus and BDNF in the frontal cortex. The decreases shown in NGF and BDNF is contrary to past findings that have shown nicotine to produce significant increases of hippocampal NGF and BDNF, but these past studies utilized male rats or mice or were performed in vitro. This study shows that nicotine has complex interactions with NGF and BDNF in D2-primed and control animals, and emphasizes the importance of gender differences when analyzing nicotine's effects on neurotrophins.