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Letteratura scientifica selezionata sul tema "Behaviour of mammals"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 20 febbraio 2023

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Articoli di riviste sul tema "Behaviour of mammals"

1

Short, R. V. "Sexual behaviour in mammals". Global Bioethics 9, n. 1-4 (gennaio 1996): 3–10. http://dx.doi.org/10.1080/11287462.1996.10800944.

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Thinley, Jigme, Ugyen Dorji, Ugyen Tshering, Arjun Nepal, Lekey Chaida, Chaten Chaten, Kiran Rai et al. "Mineral Composition and Behaviour of Mammals at Natural Saltlicks in Jomotsangkha Wildlife Sanctuary, Bhutan". Bhutan Journal of Natural Resources and Development 7, n. 2 (31 dicembre 2020): 23–33. http://dx.doi.org/10.17102/cnr.2020.49.

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Natural saltlicks are used by mammal species mainly to supplement mineral deficiency playing critical role in animal ecology. There is information gap on the use of natural saltlicks by mammals in Bhutan. Nine natural saltlicks from Jomotsangkha Wildlife Sanctuary were purposively selected to fill this gap of information. The study aimed to assess mineral composition and ecological behaviour of mammals at natural saltlicks. Nine composite soil samples were randomly collected and nine camera traps were set up at nine saltlicks for a duration of 56 days from 2 January to 28 February, 2019. Data management and analysis were carried out using camerabase and R software. Potassium, phosphorus and sodium elements were found in the saltlicks. Camera traps yielded 419 independent events of 12 species under 10 families. Herbivores were most common (n = 390) and non-herbivores the least (n = 12). Wild dog was also captured licking salts (n = 1) which is least reported across the world. Mineral composition (r = 0.70, p < .05) and anthropogenic activities (r = 0.60, p < .05) were key factors affecting the visitation rate and ecological behaviour of mammal species. Disturbed saltlicks from Samdrupcholing Range revealed fewer individuals of mammals (n = 71) with disturbed ecological behaviour while undisturbed saltlicks from Jomotsangkha Range revealed higher individuals of mammals (n = 340) with undisturbed ecological behaviour. Therefore, anthropogenic activities at disturbed saltlicks call for planned monitoring.

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3

Larivière, Serge. "Behaviour and Ecology of Riparian Mammals". Journal of Mammalogy 81, n. 1 (febbraio 2000): 280–82. http://dx.doi.org/10.1644/1545-1542(2000)081<0280:r>2.0.co;2.

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4

Murray, A. J., N. K. Waran e R. J. Young. "Environmental Enrichment for Australian Mammals". Animal Welfare 7, n. 4 (novembre 1998): 415–25. http://dx.doi.org/10.1017/s0962728600020959.

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AbstractMany of Australia's nocturnal mammals are rare or endangered in the wild. The behavioural integrity of captive populations of endangered species can be maintained through the application of environmental enrichment techniques. This study investigated the effectiveness of feeding enrichment in promoting behavioural diversity, enclosure usage and species-typical behaviours in the ghost bat (Macroderma gigas) and the yellow-bellied glider (Petaurus australis). Animals were observed for 300 min day-1 over three consecutive time periods: baseline (12 non-consecutive days); enrichment: (12 consecutive days); and post-enrichment: (12 non-consecutive days). The use of a live insect dispenser decreased grooming and increased out-of-sight and social behaviour in the ghost bat. Artificial gum trees promoted species-typical behaviours in the yellow-bellied glider. Enrichment for nocturnal mammals had variable results and different welfare implications for these animals.

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Williams, Amanda C. de C. "Persistence of pain in humans and other mammals". Philosophical Transactions of the Royal Society B: Biological Sciences 374, n. 1785 (23 settembre 2019): 20190276. http://dx.doi.org/10.1098/rstb.2019.0276.

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Evolutionary models of chronic pain are relatively undeveloped, but mainly concern dysregulation of an efficient acute defence, or false alarm. Here, a third possibility, mismatch with the modern environment, is examined. In ancestral human and free-living animal environments, survival needs urge a return to activity during recovery, despite pain, but modern environments allow humans and domesticated animals prolonged inactivity after injury. This review uses the research literature to compare humans and other mammals, who share pain neurophysiology, on risk factors for pain persistence, behaviours associated with pain, and responses of conspecifics to behaviours. The mammal populations studied are mainly laboratory rodents in pain research, and farm and companion animals in veterinary research, with observations of captive and free-living primates. Beyond farm animals and rodent models, there is virtually no evidence of chronic pain in other mammals. Since evidence is sparse, it is hard to conclude that it does not occur, but its apparent absence is compatible with the mismatch hypothesis. This article is part of the Theo Murphy meeting issue ‘Evolution of mechanisms and behaviour important for pain’.

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6

Shelley, Sarah L., Stephen L. Brusatte e Thomas E. Williamson. "Quantitative assessment of tarsal morphology illuminates locomotor behaviour in Palaeocene mammals following the end-Cretaceous mass extinction". Proceedings of the Royal Society B: Biological Sciences 288, n. 1950 (12 maggio 2021): 20210393. http://dx.doi.org/10.1098/rspb.2021.0393.

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Mammals exhibit vast ecological diversity, including a panoply of locomotor behaviours. The foundations of this diversity were established in the Mesozoic, but it was only after the end-Cretaceous mass extinction that mammals began to increase in body size, diversify into many new species and establish the extant orders. Little is known about the palaeobiology of the mammals that diversified immediately after the extinction during the Palaeocene, which are often perceived as ‘archaic’ precursors to extant orders. Here, we investigate the locomotor ecology of Palaeocene mammals using multivariate and disparity analyses. We show that tarsal measurements can be used to infer locomotor mode in extant mammals, and then demonstrate that Palaeocene mammals occupy distinctive regions of tarsal morphospace relative to Cretaceous and extant therian mammals, that is distinguished by their morphological robustness. We find that many Palaeocene species exhibit tarsal morphologies most comparable with morphologies of extant ground-dwelling mammals. Disparity analyses indicate that Palaeocene mammals attained similar morphospace diversity to the extant sample. Our results show that mammals underwent a post-extinction adaptive radiation in tarsal morphology relating to locomotor behaviour by combining a basic eutherian bauplan with anatomical specializations to attain considerable ecomorphological diversity.

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Delgado-Martínez, Carlos M., Fredy Alvarado, Melanie Kolb e Eduardo Mendoza. "Monitoring of small rock pools reveals differential effects of chronic anthropogenic disturbance on birds and mammals in the Calakmul region, southern Mexico". Journal of Tropical Ecology 38, n. 2 (17 dicembre 2021): 79–88. http://dx.doi.org/10.1017/s0266467421000547.

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AbstractGreat attention has been drawn to the impacts of habitat deforestation and fragmentation on wildlife species richness. In contrast, much less attention has been paid to assessing the impacts of chronic anthropogenic disturbance on wildlife species composition and behaviour. We focused on natural small rock pools (sartenejas), which concentrate vertebrate activity due to habitat’s water limitation, to assess the impact of chronic anthropogenic disturbance on the species richness, diversity, composition, and behaviour of medium and large-sized birds and mammals in the highly biodiverse forests of Calakmul, southern Mexico. Camera trapping records of fauna using sartenejas within and outside the Calakmul Biosphere Reserve (CBR) showed that there were no effects on species richness, but contrasts emerged when comparing species diversity, composition, and behaviour. These effects differed between birds and mammals and between species: (1) bird diversity was greater outside the CBR, but mammal diversity was greater within and (2) the daily activity patterns of birds differed slightly within and outside the CBR but strongly contrasted in mammals. Our study highlights that even in areas supporting extensive forest cover, small-scale chronic anthropogenic disturbances can have pervasive negative effects on wildlife and that these effects contrast between animal groups.

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Miller, Lance J., Moby Solangi e Stan A. Kuczaj. "Immediate response of Atlantic bottlenose dolphins to high-speed personal watercraft in the Mississippi Sound". Journal of the Marine Biological Association of the United Kingdom 88, n. 6 (17 marzo 2008): 1139–43. http://dx.doi.org/10.1017/s0025315408000908.

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Measuring the impact of anthropogenic factors on marine mammals is critical to the conservation of these species. Recently, the effect of personal watercraft on marine mammal behaviour and well-being has become a topic of increasing concern. The purpose of this study was to examine the immediate effects of high-speed personal watercraft on Atlantic bottlenose dolphin (Tursiops truncatus) behaviour. Opportunistic surveys were conducted from a research vessel in the Mississippi Sound (30º13′22.6″N 89º01′36.5″W) from September 2003 through to August 2005. The passing of a high-speed personal watercraft significantly increased dolphin dive duration, dolphin group cohesion and dolphin breathing synchrony. Additionally, in 47% of the encounters a dolphin group's behaviour changed within one minute of the presence of a high-speed personal watercraft. The most notable changes were an increase in dolphin travelling behaviour and a decrease in feeding behaviour following the boat's presence. The results demonstrated an immediate, short-term change in dolphin behaviour, suggesting that an increase in the frequency of high-speed personal watercraft in this area could produce long-term detrimental effects. Research on the long-term effects of boat traffic on marine mammals is clearly needed to assess and hopefully mediate any potential long-term effects.

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Stewart, F. E. C., e A. G. McAdam. "Wild Peromyscus adjust maternal nest-building behaviour in response to ambient temperature". Canadian Journal of Zoology 95, n. 6 (giugno 2017): 411–15. http://dx.doi.org/10.1139/cjz-2016-0236.

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The heat dissipation limit (HDL) hypothesis suggests that energy output during lactation in mammals might be constrained by their ability to dissipate heat. This hypothesis predicts that wild mammals ought to adjust nest insulation in response to heat load, but these predictions have rarely been tested in wild mammals. Here we developed a simple score of nest-building for wild deer mice (Peromyscus maniculatus (Wagner, 1845)) on an ordinal scale from 0 to 4, based on three qualitative and easy to observe aspects of nest-building behaviour: bedding quality, nest shape, and mouse visibility. We used this measure to track 472 nest-building observations across 14 wild P. maniculatus that were brought into captivity and housed under pseudoambient temperatures across one reproductive event. Our observations of nest-building behaviour of the genus Peromyscus Gloger, 1841 provide varying support for the HDL hypothesis; there is a negative effect of ambient temperature on nest-building behaviour and lactating females became more sensitive to temperature as days post partum increased. However, females generally build more elaborate nests in lactation than other reproductive states and there are no effects of litter size, total pup mass, or days post partum on nest scores during lactation. Our observations have broad implications for quantifying behaviours in nest-building species and metabolic relationships in wild mammals.

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Poindron, Pascal. "Mechanisms of activation of maternal behaviour in mammals". Reproduction Nutrition Development 45, n. 3 (maggio 2005): 341–51. http://dx.doi.org/10.1051/rnd:2005025.

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Tesi sul tema "Behaviour of mammals"

1

Jensen, Susanne Plesner. "Ecology and behaviour of small mammals on expanded field margins". Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336050.

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Ca¨sar, Cristiane. "Anti-predator behaviour of black-fronted titi monkeys (Callicebus nigrifrons)". Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/2575.

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Titi monkeys have long been known for their complex vocal behaviour with numerous high- and low-pitched calls, which can be uttered singly or combined in more complex structures. However, up to date very little is known concerning the function, meaning and context-specific use of these vocal utterances, and virtually nothing is known about their vocalisations in the predation context. This thesis presents a detailed description of the form and function of the anti-predator behaviour of one species of titi monkeys, the black-fronted titi monkey (Callicebus nigrifrons), with a specific focus on their alarm call behaviour. A second aim was to determine the exact mechanisms of alarm calling behaviour, with an emphasis on production and comprehension. Data were collected from several habituated groups in the Caraça Reserve, Minas Gerais, Brazil. Results showed that, when detecting predator species, C nigrifrons produce sequences that initially contain two types of brief, high-pitched calls with distinct frequency contours. Further evidence suggested that some of these sequences are meaningful to conspecific receivers, by indicating the general predator class and location of threat. There were also indications that, within the terrestrial threats, additional information may be encoded by acoustic and compositional differences. Analyses of call order and number of calls per sequence suggested that callers may be able to convey information on both predator type and location. The black-fronted titi monkeys’ vocal system thus provides a further example of zoo-syntax, in which acoustically fixed units of a vocal repertoire are combined into higher order sequences that are meaningful to recipients. According to current definitions, this type of calling behaviour qualifies as functionally referential, by indicating general predator class, terrestrial predator type and location. As such, this is the first empirical demonstration of a sequence-based alarm call system that conveys information on both predator category and location.

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Ames, Alison Lorraine. "The management and behaviour of captive polar bears". Thesis, Open University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340676.

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Farrand, Alexandra. "The effect of zoo visitors on the behaviour and welfare of zoo mammals". Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/300.

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There is evidence that the presence of the visiting public affects the behaviour of zoo-housed mammals. Understanding the effect of visitors is important in improving animal welfare, achieving zoo conservation goals, increasing visitor education/entertainment, and facilitating interpretation of data on zoo animal biology. A series of studies and experiments focusing on the effect of zoo visitors on captive mammal behaviour is presented. The influence of visitor density on a range of primates and large carnivores is examined. Methodological concerns regarding the operational definition of visitor density in the literature are expressed and a clarification of terms which may be helpful when comparing previous research is provided. Visitor noise data, using an objective measure of the variable, and its relationship to visitor density are also presented. External and internal visual barriers between visitors and zoo animals were hypothesised to moderate the visitor effect and enrich the environment of the study groups. Camouflage nets mounted on the outside of enclosure viewing windows had little impact on primate or felid behaviour, with the exception of the Sumatran orangutan group, who showed a trend toward decreased social play in the presence of the external barrier. Polar bear behaviour showed evidence of an enriched environment, with trends toward increased levels of swimming and decreased levels of resting. An internal visual barrier, which prevented visitors from having visual contact with the golden lion tamarins when the nonhuman primates were behind it, was also tested and elicited more extensive trends toward behavioural change than did the nets. Both Sumatran orangutans and zoo visitors were provided with a similar puzzle feeder in an effort to enrich the orangutan enclosure, and improve the visitor experience. It was hypothesised that the orangutans might be stimulated by watching visitors manipulate the device, but this did not occur. Orangutan use of the puzzle feeder within their enclosure was also unaffected. Olfactory stimuli were introduced into primate and felid enclosures and visitor viewing areas to investigate the role olfaction may play in the visitor effect. Although olfactory stimuli had an extensive significant effect on the behaviour of the study groups when it was introduced into the enclosure, there was little change when visitors were associated with the olfactory stimuli which suggest there may not be an olfactory visitor effect in primates or felids. The effect of visitors on petting zoo-housed mixed-breed goats, llama, and Vietnamese pot-bellied pigs was studied and compared to their behaviour without the presence of visitors. The goats were unaffected and the llama showed only a trend toward decreased levels of sitting in the presence of visitors. The Vietnamese pot-bellied pigs were significantly affected by the presence of visitors, exhibiting decreased inactivity and social behaviour. The hypothesis that a sustained absence of visitors would result in a more intense visitor effect was tested and was not supported by the data. An additional experiment investigating the effect of visitor grooming on the petting zoo study species showed that, while visitors spent more time interacting with the animals in the grooming condition, xiv the behaviour of the study animals indicated that they did not find visitor grooming rewarding. Data on the interaction between visitor density and the various experimental techniques tested here indicate that visitor density may impact animal response to environmental enrichment, supporting previous findings in the literature. In the presence of visual barriers, foraging devices, and olfactory stimuli, the relationship between animal behaviour and visitor density changed significantly, both qualitatively and quantitatively. These results suggest that collecting visitor density data when testing environmental enrichment techniques could be helpful when assessing their effectiveness, ultimately improving the welfare of zoo-housed mammals. Based on the data presented here, in conjunction with the literature, a closing discussion outlines proposed refinements to the visitor effect research guidelines published by the British and Irish Association of Zoos and Aquariums (2005).

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Stephens, Philip Andrew. "Behaviour based models population dynamics and the conservation of social mammals". Thesis, University of East Anglia, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251708.

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Zabaras, Regina, University of Western Sydney, of Science Technology and Environment College e of Science Food and Horticulture School. "The evolution of semiochemicals in Australian marsupials". THESIS_CSTE_SFH_Zabaras_R.xml, 2003. http://handle.uws.edu.au:8081/1959.7/759.

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The aim of this project was to study the nature and relative proportion of the volatile components in the sternal-gland secretions obtained from a wide range of Australian marsupials.The results obtained were then used to investigate the evolution of semiochemicals in Australian marsupials by using the current phylogenetic tree as a template.The initial part of the study was dedicated to the investigation of some of the techniques available for the sampling and analysis of gland secretions. Individuals from 8 families within the Marsupialia and 1 family from the Monotremata were sampled over an 18 month period.The obtained results were then subjected to multivariate statistical analysis followed by cladistic analysis.In several species the secretion composition was found to be affected by the breeding status of individuals for both genders.Many other factors such as animal-age, hierarchical status, diet,and lifestyle were also observed to affect the secretion composition. Finally, cladistic analysis demonstrated the differences in the levels of divergence at the species, familial and ordinal levels and highlighted secretion components that could be used to differentiate between super families, species and even sexual status of individuals.
Master of Science (Hons)

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Vitale, Jessica. "The olfactory behaviour of spotted hyaenas (Crocuta crocuta) and sympatric mammals in the Okavango Delta, Botswana". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48855/.

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Understanding the natural behaviour and coexistence of species is important for the conservation of intact ecosystems, and behavioural studies can enhance our knowledge of processes such as communication and competition. I investigated the social dynamics and scent-marking behaviour of spotted hyaenas (Crocuta crocuta), and the occurrence of interspecific olfactory eavesdropping among African mammals, within the Okavango Delta ecosystem of Botswana. First, social network analysis found that the hyaena population was comprised of five main clans that maintained territories but whose home ranges overlapped considerably. Scavenging at large carcasses involved associations between individuals from different clans and resulted in relative tolerance toward territorial intruders. Second, observations of communal latrine use found that latrines are likely involved in territorial advertisement by hyaena clans, and cyclical patterns of latrine growth and decline were linked to annual rainfall. Third, a translocation experiment showed that hyaena scats appear to be less important for hyaena communication than other cues associated with latrines, especially as hyaenas did not differ in their behaviour towards scat originating from latrines located in resident versus non-resident clan home ranges. Heterospecific mammals investigated, scent-marked, and were vigilant at hyaena latrines, suggesting a potential function for hyaena latrines in interspecific eavesdropping and/or communication. Fourth, a urine presentation experiment found that the investigation of sympatric predator urine by African mammals stimulated vigilance behaviour, suggesting that olfactory signals provide information about predation risk. Hyaenas exhibited context-specific differences in behaviour towards predator urine: they were more likely to investigate urine samples alongside indicators of predator activity (i.e. carrion odour, carcasses) and were most likely to exhibit vigilance at carcasses when exposed to urine from lions and wild dogs. This study greatly enhanced our understanding of spotted hyaena behaviour within the Okavango Delta, an important ecosystem for the conservation of African large predators. Furthermore, this study provided the first experimental evidence of the role of hyaena scats in intraspecific communication and interspecific olfactory eavesdropping at latrines. My research findings regarding the population’s clan structure and home ranges will form the foundation for subsequent investigation into human-wildlife conflict in the study area. Furthermore, the results from two scent experiments shed light on the potential importance of olfactory signals for mediating interspecific interactions among African mammals, particularly among large predators.

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Hanlan, Suzanne K. "Nosing behaviour in captive harbour seals (Phoca vitulina concolor) : implications for olfaction and affiliation /". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0015/MQ42389.pdf.

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Shelley, Sarah Laura. "The rise of placental mammals : the anatomy, palaeobiology and phylogeny of Periptychus and the Periptychidae". Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/29539.

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The diversification of eutherian mammals following the end-Cretaceous mass extinction was a critical period in evolutionary history. The Palaeocene is marked by the proliferation of archaic mammals which exhibit a mosaic of primitive and derived anatomies and whose phylogenetic affinities with extant mammals remain contentious. Consequently, macroevolutionary studies assessing the timing and recovery of eutherian mammals following the end-Cretaceous mass extinction are inhibited by our relatively poor knowledge of the mammals which thrived during the Palaeocene. One group of Palaeocene mammals in particular, the ‘Condylarthra’ have proven especially enigmatic and, as historically conceived, includes families of ungulate-grade mammals some of which are considered the ancestral stock from which modern perissodactyls and artiodactyls arose. The Periptychidae are a distinctive ‘condylarth’ family and were among the first mammals to appear after the extinction. As such they constitute an excellent empirical case study towards resolving the evolutionary relationships and understanding the palaeobiology of Palaeocene mammals. The overarching aim of this thesis has been to generate a comprehensive higher-level phylogenetic hypothesis of Periptychidae and shed light on the species-level interrelationships of taxa historically identified as periptychids and other ‘condylarth’ exemplars. This aim has been achieved by the undertaking a comprehensive anatomical re-description of the archetypal periptychid, Periptychus carinidens, based on a wealth of new fossils recovered from the San Juan Basin in New Mexico, USA. The anatomical information described in this thesis has also facilitated a greater understanding of ecology and functional morphology of Periptychus and its kin. Periptychus carinidens was a medium-sized, robust, stout-limbed animal that was mediportal and adopted a plantigrade mode of locomotion. The cranial and dental anatomy of Periptychus is broadly concurrent with the inferred plesiomorphic eutherian condition albeit more robust in its overall construction. The broad facial region, tall sagittal and nuchal crests and distinctive dentition with strong enamel crenulations and compressive wear are likely indicative of durophagous diet made up of dense, fibrous, plant-based food stuffs. The postcranial skeleton of Periptychus is a miscellany of morphologies with often paradoxical functional implications. Despite its robustness, Periptychus retained a moderately high degree of multiaxial movement and dexterity in its limbs with prominent muscle attachment sites indicative of powerful, non-rapid limb movements. Well-developed manual and digital flexors and extensors are further indicative of some scansorial and fossorial capability. Periptychus and other Palaeocene mammals are characterised by their robust anatomy and tend to lack any obvious extant analogues impeding our understanding of eutherian ecological diversity during the Palaeocene and the roles of many so-called ‘archaic’ mammals. Multivariate analyses on a dataset of functionally significant limb measurements show that Palaeocene mammals exhibit a distinct and more constrained range of locomotor ability defined by their prevalent robust morphology. However, there are subtle distinctions between archaic taxa indicating ecomorphical diversity possibly due to niche partitioning, that are not easily comparable to extant mammals. This suggests that, far from being generalized ancestral stock, Palaeocene taxa were experimenting with their own unique locomotor styles. The extinction of many archaic groups at the end of the Palaeogene is associated with a trend towards increasingly open habitats, which was less conducive to the survivorship of robust, ambulatory mammals. The anatomy of Periptychus combines a basic early placental body plan with numerous unique specialisations in its dental, cranial and postcranial anatomy that not only exemplify the ability of mammals to adapt and evolve following catastrophic environmental upheaval but provide a prime exemplar by which to tackle the taxonomic and systematic conundrum that is ‘Condylarthra’. A cladistic analysis was conducted to determine the phylogenetic affinities of Periptychidae within Placentalia. 141 taxa were scored for 503 characters including 40 periptychid species and 63 novel characters. The dataset was analysed under parsimony optimality criteria and the resulting phylogeny shows a well resolved strict consensus topology with numerous well-supported relationships which help elucidate periptychid phylogeny. The analysis presented here finds Periptychidae as a monophyletic group to the exclusion of several purported periptychid taxa which are recovered with the ‘arctocyonid’, Baioconodon nordicum. The in-group relationships of Periptychidae are resolved to broadly support the subfamilial arrangement proposed by previous workers. Alticonus is recovered the most basal, unambiguous periptychid taxon. Ampliconus forms a paraphyletic stem from Alticonus to all other unequivocal periptychid taxa. Conacodontinae forms a clade which includes Auraria as the most basal taxon relative to Oxyacodon, which forms a paraphyletic stem to Conacodon. The hypsodont periptychids, Haploconus + Goleroconus form a clade, separate from both ‘Anisonchinae’ and Conacodontinae, both of which they have previously been affiliated to. ‘Anisonchinae’ forms a paraphyletic stem relative to Periptychinae. Mithrandir oligustus is the most basal ‘anisonchine’. Gillisonchus is generically distinct from both Mithrandir and ‘Anisonchus’ due to morphological similarities with Hemithlaeus and the Periptychinae. Periptychinae forms a well-supported clade with Hemithlaeus and Tinuviel resolved to be more closely related to Ectoconus than Periptychus + Carsioptychus. Periptychus is a member of Periptychinae and most closely related to Carsioptychus within Periptychini. The phylogeny reported here indicates that Periptychidae were an incredibly successful family during much of their early history and were particularly prolific during the middle Puercan. Most species were small to medium sized animals; however, members of Periptychinae attained large body sizes within less than half a million years of the end-Cretaceous mass extinction. Periptychids were prolific during early Puercan, but spent the majority of their evolutionary history exhibiting high turnover, with many short-lived species, with the notable exception of three genera: Anisonchus, Haploconus and Periptychus, which prevailed through the Torrejonian. These periptychids are among the most enduring Palaeocene taxa known and reiterate the importance of the Periptychidae in understanding the recovering and radiation of Placentalia following the end-Cretaceous mass extinction.

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Oliver, Colin Malcolm. "The role of the ram in the impala (Aepyceros melampus) mating system". Diss., University of Pretoria, 2002. http://upetd.up.ac.za/thesis/available/etd-03292005-104752/.

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Più fonti

Libri sul tema "Behaviour of mammals"

1

Social behaviour in mammals. Glasgow: Blackie, 1985.

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2

Poole, Trevor B. Social behaviour in mammals. Glasgow: Blackie, 1985.

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3

Poole, Trevor B. Social Behaviour in Mammals. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7.

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4

Macdonald, David W. Collins European mammals: Evolution and behaviour. London: HarperCollins, 1995.

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5

Collins European mammals: Evolution and behaviour. London: HarperCollins, 1995.

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6

Portraits in the wild: Animal behaviour in East Africa. London: Elm Tree, 1989.

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7

Richard, Du Toit, a cura di. Creatures of habit: Understanding African animal behaviour. Cape Town: Struik, 2000.

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8

W, Sluckin, e Herbert Martin, a cura di. Parental behaviour. Oxford, OX, UK: Basil Blackwell, 1986.

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9

Programme, United Nations Environment, e Secretariat, Convention on Migratory Species, a cura di. Review of small cetaceans: Distribution, behaviour, migration and threats. Bonn, Germany: UNEP/CMS Secretariat, 2004.

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10

Apps, Peter. Wild ways: A field guide to the behaviour of southern African mammals. Halfway House: Southern Book Publishers, 1992.

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Capitoli di libri sul tema "Behaviour of mammals"

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Poole, Trevor B. "Reproductive Behaviour". In Social Behaviour in Mammals, 40–81. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_3.

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Poole, Trevor B. "Competitive and Affiliative Behaviour". In Social Behaviour in Mammals, 82–119. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_4.

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Poole, Trevor B. "Introduction". In Social Behaviour in Mammals, 1–9. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_1.

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Poole, Trevor B. "Senses and Social Communication". In Social Behaviour in Mammals, 10–39. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_2.

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Poole, Trevor B. "Socioecology". In Social Behaviour in Mammals, 120–55. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_5.

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Poole, Trevor B. "An Order-by-Order Synopsis of Social Behaviour". In Social Behaviour in Mammals, 156–96. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_6.

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Poole, Trevor B. "Future Developments". In Social Behaviour in Mammals, 197–200. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2345-7_7.

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Liu, Yu Hsin, e Satchidananda Panda. "Circadian Photoentrainment Mechanism in Mammals". In Biological Timekeeping: Clocks, Rhythms and Behaviour, 365–93. New Delhi: Springer India, 2017. http://dx.doi.org/10.1007/978-81-322-3688-7_17.

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Goy, Robert W., e Marc Roy. "Heterotypical Sexual Behaviour in Female Mammals". In Heterotypical Behaviour in Man and Animals, 71–97. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3078-3_4.

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Reckendorf, Anja, Lars Seidelin e Magnus Wahlberg. "Marine Mammal Acoustics". In Marine Mammals, 15–31. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-06836-2_2.

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AbstractBioacoustics combines the fields of biology and acoustics to answer questions about hearing, sound production and sound communication in animals. Marine mammals have specialised hearing abilities and use sounds in different ways underwater. How do whales and seals use sound for communication and to find prey? How are they affected by human-made sounds from ships, oil exploration and windfarms? To answer such questions, you need to study marine mammals, be well-trained in natural sciences and know about animal anatomy, physiology and behaviour. You also need a thorough understanding of the fundamentals of acoustics, maths and physics. Bioacoustics is a truly interdisciplinary research field involving biologists, physicists and engineers trying to understand the world of biological sound, how sounds are produced and used by animals. Additionally, underwater acoustic recordings can reveal which areas animals use during different seasons. Bioacoustics can also be used to improve wildlife protection by regulating damaging sound sources in marine mammal habitats. Using the exercises at the end of this chapter, students learn about frequencies, decibels and their own hearing abilities, as well as how to build their own underwater microphone.

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Atti di convegni sul tema "Behaviour of mammals"

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Bagnoli, Paola, Adriano Zaffora, Bruno Cozzi, Roberto Fumero e Maria Laura Costantino. "Experimental and Computational Biomechanical Characterization of the Dolphin Tracheo-Bronchial Tree During Diving". In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19078.

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Marine mammals belonging to the Order of CetoArtiodactyla have developed their organs and adapted their anatomic structures to survive and better exploit the resources of the surrounding water environment. Though belonging to the Mammal Class and, hence, having a cardio-respiratory system based on the gas exchange with the atmosphere, they are able to perform long-lasting immersions and reach considerable depths during diving [1]. On the other hand, the anatomy of the tracheo-bronchial structures of the Family Delfinidae differs from that of terrestrial mammals in the lack of muscular tissue in the posterior region and the irregular shape of the cartilaginous rings (Fig.1a-b-c) [1, 2]. So far, the behavior of dolphin respiratory system during diving is not yet fully understood, since they cannot be subjected to invasive analysis being endangered and protected species. Namely, it remains to ascertain whether the tracheo-bronchial tree collapses during diving or is kept open by the peculiar material properties, the anatomical structure and the presence of entrapped air. Aim of this work is to model the dolphin Tursiops truncatus’s tracheo-bronchial tree to study its behavior during diving by coupling experimental in vitro mechanical characterization of airways tissues to finite element computational analyses. Furthermore, we performed a comparison between the mechanical behavior of tracheo-bronchial trees of dolphins and that of the goat, a terrestrial mammal whose conformation of the upper airways is similar to the human, to highlight discrepancies due to the different habitats.

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Kopman, Vladislav, Nicholas Cavaliere e Maurizio Porfiri. "A Thrust-Vectored Submersible for Animal Behavior Research: Design and Proof of Concept". In ASME 2010 Dynamic Systems and Control Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/dscc2010-4093.

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In this paper, we present the design and proof of concept of a streamlined, low-cost, and smooth-hulled underwater vehicle (MASUV-1). MASUV-1 utilizes an ad-hoc designed multi-directional thrust-vectoring system for steering and an entirely enclosed propulsion system, allowing for safe operation in the vicinity of marine mammals. Tests of the vehicle in a still water environment show high maneuverability at speeds comparable with similar torpedo-type class underwater vehicles.

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"Social behavior and spatial memory in tame and aggressive mammals". In Bioinformatics of Genome Regulation and Structure/Systems Biology (BGRS/SB-2022) :. Institute of Cytology and Genetics, the Siberian Branch of the Russian Academy of Sciences, 2022. http://dx.doi.org/10.18699/sbb-2022-399.

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Shvyreva, Elena Alexandrovna. "Influence of tetrahydrocarbazole derivatives on orientation behavior and contextual memory of mammals". In IX International applied research conference. TSNS Interaktiv Plus, 2016. http://dx.doi.org/10.21661/r-112305.

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Deng, ShiChao, Guizhong Tang e Lei Mei. "Wild Mammal Behavior Recognition Based on Gated Transformer Network". In 2022 International Conference on Cyber-Physical Social Intelligence (ICCSI). IEEE, 2022. http://dx.doi.org/10.1109/iccsi55536.2022.9970674.

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Ahrens, Andrea, Jeffrey Green, Paul Anderson e Linda Postlewaite. "Why Marine Mammals Matter to Your Terrestrial Export Pipeline Project". In 2014 10th International Pipeline Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/ipc2014-33752.

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Increases in export pipeline development can result in a corresponding increase in marine transportation activities and the potential to escalate adverse interactions with marine wildlife. Ship traffic introduces risks of vessel strikes as well as the amount of underwater noise produced in the marine environment. Growing public and scientific concern over the potential effects of increasing ship traffic on marine wildlife mean that even terrestrially-based pipeline projects need to start considering the effects of shipping in developing environmental mitigation programs for their export operations. Northern Gateway is proposing to construct and operate twin pipelines between Alberta and British Columbia, and an associated tank and marine terminal for export operations. While Northern Gateway will not own or operate any of the tankers, they have committed to implementing a comprehensive marine mitigation, monitoring and research program, including measures to reduce ship strikes and effects of underwater noise on marine mammals. Vessel strikes can cause severe or fatal injuries. Higher relative risk exists where shipping traffic overlaps with increased densities of marine mammals. Vessel speed has been positively correlated with the degree of risk and injury; consequently, Northern Gateway has set maximum year-round speed restrictions of 10–12 knots for all Project-related tankers calling at the marine terminal, with further restrictions of 8–10 knots in key areas. Other large vessels in this region currently travel at speeds of 16–21 knots. Mandatory speed restrictions will also reduce the Project’s contribution to underwater noise. Effects of underwater noise on marine mammals include temporary habitat avoidance, reduced feeding efficiency, behavioural change, increased stress, and communication masking. Acoustic modeling conducted for the project predicted that reducing vessel speeds from 15 to 9.6 knots would decrease underwater noise input by nearly 12 dB, making the zone of ensonification 2–3 times smaller than in the absence of mitigations. Purpose-built escort tugs will use best commercially-available noise-quieting technology and speed restriction areas will be refined through six-years of surveys and a quantitative vessel strike analysis. Vessel traffic is not unique to Northern Gateway; however, through minimizing their incremental contribution, they hope to serve as an industry example. This approach to minimizing effects of routine marine export operations is unique in the shipping industry in Canada and the United States. If other proponents were to adopt similar types of measures, Northern Gateway believes that the marine environment would see some net benefits in terms of a reduction in adverse effects on marine mammals.

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Labak, Stanley J. "A Submariner’s perspective on marine mammal passive acoustic perception and subsequent behavior". In Fourth International Conference on the Effects of Noise on Aquatic Life. Acoustical Society of America, 2016. http://dx.doi.org/10.1121/2.0000297.

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Anderson, Torri, Christopher Cali, Katherine Bell, Keith G. Danielson, Ashley Klein, Christina Martin, Sara Radecki, Adam Santoro, John A. Schmidt e Janice E. Knepper. "Abstract 3391: Alteration of mammary tumor cell behavior by FLIZ1". In Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA. American Association for Cancer Research, 2014. http://dx.doi.org/10.1158/1538-7445.am2014-3391.

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Lee, JS, MH Park e JH Yoon. "P2-11-05: Stromal Matrix Metalloproteinase-14 Expression Correlates with the Grade and Biological Behavior of Mammary Phyllodes Tumors." In Abstracts: Thirty-Fourth Annual CTRC‐AACR San Antonio Breast Cancer Symposium‐‐ Dec 6‐10, 2011; San Antonio, TX. American Association for Cancer Research, 2011. http://dx.doi.org/10.1158/0008-5472.sabcs11-p2-11-05.

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Mollaeian, Keyvan, Yi Liu e Juan Ren. "Investigation of Nanoscale Poroelasticity of Eukaryotic Cells Using Atomic Force Microscopy". In ASME 2017 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/dscc2017-5254.

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Intracellular network deformation of the cell plays an important role in cellular shape formation. Recent studies suggest that cell reshaping and deformation due to external forces involves cellular volume, pore size, elasticity, and intracellular filaments polymerization rate changes. This behavior of live cells can be described by poroelastic models because of the porous structure of the cytoplasm. In this study, the poroelasticity of human mammary basel/claudin low carcinoma cell (MDA-MB-231) was investigated using indentation-based atomic force microscopy. The effects of cell deformation (i.e., indentation) rate on the poroelasticity of MDA-MB-231 cells were studied. Specifically, the cell poroelastic behavior (i.e., the diffusion coefficient) was quantified at different indenting velocities (0.2, 2, 10, 20, 100, 200 μm/s) by fitting the force-relaxation curves using a poroelastic model. It was found that the in general the MDA-MB-231 cells behaved poroelastic, and they were less poroelastic (i.e., with lower diffusion coefficient) at higher indenting velocities due to the local stiffening up caused by faster force loads. Poor poroelastic relaxation was observed when the indenting velocity was lower than 10 μm/s due to the intracelluar fluid redistribution during the slow indenting process to equilibrate the intracellular pressure. Moreover, the measurement results showed that the pore size reduction caused by local stiffening at faster indenting velocities is more dominant than the Young’s modulus in affecting the cell poroelasticity.

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Rapporti di organizzazioni sul tema "Behaviour of mammals"

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Clark, Christopher W., Daniel P. Costa e Walter H. Munk. Potential Effects of Low Frequency Sounds on Distribution and Behavior of Marine Mammals. Fort Belvoir, VA: Defense Technical Information Center, settembre 2000. http://dx.doi.org/10.21236/ada383534.

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Costa, Daniel P., e Scott A. Shaffer. A Database for the Study of Marine Mammal Behavior: A Tool to Define Their Critical Habitat and Behavior. Fort Belvoir, VA: Defense Technical Information Center, agosto 2003. http://dx.doi.org/10.21236/ada416440.

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Williams, Terrie M. High Risk Behaviors in Marine Mammals: Linking Behavioral Responses to Anthropogenic Disturbance to Biological Consequences. Fort Belvoir, VA: Defense Technical Information Center, settembre 2013. http://dx.doi.org/10.21236/ada602529.

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Houser, Dorian S. Integration of Marine Mammal Movement and Behavior into the Effects of Sound on the Marine Environment. Fort Belvoir, VA: Defense Technical Information Center, settembre 2009. http://dx.doi.org/10.21236/ada531191.

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Houser, Dorian S. Integration of Marine Mammal Movement and Behavior into the Effects of Sound on the Marine Environment. Fort Belvoir, VA: Defense Technical Information Center, settembre 2010. http://dx.doi.org/10.21236/ada541680.

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El Halawani, Mohamed, e Israel Rozenboim. Temperature Stress and Turkey Reproduction. United States Department of Agriculture, maggio 2002. http://dx.doi.org/10.32747/2002.7570546.bard.

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High temperature stress is of major concern to turkey producers in Israel and the United States. The decline in the rate of egg production at high environmental temperature is well recognized, but the neuroendocrinological basis is not understood. Our objectives were: 1) to characterize the hypothalamo-hypophyseal axis involvement in the mechanism(s) underlying the detrimental effect of heat stress on reproduction, and 2) to establish procedures that alleviate the damaging effect of heat stress on reproduction. Heat stress (40oC, Israel; 32oC, U.S.) caused significant reduction in egg production, which was restored by VIP immunoneutralization. The decline in egg production did not appear to be entirely related to the expression of incubation behavior due to the rise in circulating PRL in stressed birds. Heat stress was found to increase circulating PRL in ovariectomized turkeys independent of the reproductive stage. Active immunization against VIP was shown for the first time to up-regulate LHb and FSHb subunit mRNA contents. These findings taken together with the results that the heat stress-induced decline in egg production may not be dependent upon the reproductive stage, lead to the suggestion that the detrimental effect of heat stress on reproductive performance may be in part mediated by VIP acting directly on the GnRH/gonadotropin system. Inhibin (INH) immunoneutralization has been shown to enhance FSH secretion and induces ovulation in mammals. It is hypothesized that immunization of heat-stressed turkeys against INH will increase levels of circulating FSH and the number of preovulating follicles which leads to improved reproductive performance. We have cloned and expressed turkey INH-a and INH-bA. Active immunization of turkey hens with rtINH-a increased pituitary FSH-b subunit mRNA and the number of non-graded preovulatory yellow follicles, but no significant increase in egg production was observed.

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Gothilf, Yoav, Roger Cone, Berta Levavi-Sivan e Sheenan Harpaz. Genetic manipulations of MC4R for increased growth and feed efficiency in fish. United States Department of Agriculture, gennaio 2016. http://dx.doi.org/10.32747/2016.7600043.bard.

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The hypothalamic melanocortin system plays a central role in the regulation of food consumption and energy homeostasis in mammals. Accordingly, our working hypothesis in this project was that genetic editing of the mc4r gene, encoding Melanocortin Receptor 4 (MC4R), will enhance food consumption, feed efficiency and growth in fish. To test this hypothesis and to assess the utility of mc4r editing for the enhancement of feed efficiency and growth in fish, the following objectives were set: Test the effect of the mc4r-null allele on feeding behavior, growth, metabolism and survival in zebrafish. Generate mc4r-null alleles in tilapia and examine the consequences for growth and survival, feed efficiency and body composition. Generate and examine the effect of naturally-occurring mc4r alleles found in swordfish on feeding behavior, growth and survival in zebrafish. Define the MC4R-mediated and MC4R-independent effects of AgRP by crossing mc4r- null strains with fish lacking AgRP neurons or the agrpgene. Our results in zebrafish did not support our hypothesis. While knockout of the agrpgene or genetic ablation of hypothalamic AgRP neurons led to reduced food intake in zebrafish larvae, knockout (KO) of the mc4r gene not only did not increase the rate of food intake but even reduced it. Since Melanocortin Receptor 3 (MC3R) has also been proposed to be involved in hypothalamic control of food intake, we also tested the effectofmc3r gene KO. Again, contrary to our hypothesis, the rate of food intake decreased. The next step was to generate a double mutant lucking both functional MC3R and MC4R. Again, the double KO exhibited reduced food intake. Thus, the only manipulation within the melanocortin system that affected food intake in consistent with the expected role of the system was seen in zebrafish larvae upon agrpKO. Interestingly, despite the apparent reduced food intake in the larval stage, these fish grow to be of the same size as wildtype fish at the adult stage. Altogether, it seems that there is a compensatory mechanism that overrides the effect of genetic manipulations of the melanocortin system in zebrafish. Under Aim 3, we introduced the Xna1, XnB1l, and XnB2A mutations from the Xiphophorus MC4R alleles into the zebrafish MC4R gene. We hypothesized that these MC4R mutations would act as dominant negative alleles to increase growth by suppressing endogenous MC4R activity. When we examined the activity of the three mutant alleles, we were unable to document any inhibition of a co-transfected wild type MC4R allele, hence we did not introduce these alleles into zebrafish. Since teleost fish possess two agrpgenes we also tested the effect of KO of the agrp2 gene and ablation of the AgRP2 cells. We found that the AgRP2 system does not affect food consumption but may rather be involved in modulating the stress response. To try to apply genetic editing in farmed fish species we turned to tilapia. Injection of exogenous AgRP in adult tilapia induced significant changes in the expression of pituitary hormones. Genetic editing in tilapia is far more complicated than in zebrafish. Nevertheless, we managed to generate one mutant fish carrying a mutation in mc4r. That individual died before reaching sexual maturity. Thus, our attempt to generate an mc4r-mutant tilapia line was almost successful and indicate out non-obvious capability to generate mutant tilapia.

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