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Author |
Flack, J.C.; Krakauer, D.C.; de Waal, F.B.M. |
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Title |
Robustness mechanisms in primate societies: a perturbation study |
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Journal Article |
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Year |
2005 |
Publication |
Proceedings. Biological sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
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Volume |
272 |
Issue |
1568 |
Pages |
1091-1099 |
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Keywords |
Aggression/physiology; Animals; *Conflict (Psychology); Female; *Hierarchy, Social; Macaca nemestrina/*physiology; Male; *Models, Theoretical; Observation; *Social Behavior |
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Abstract |
Conflict management mechanisms have a direct, critical effect on system robustness because they mitigate conflict intensity and help repair damaged relationships. However, robustness mechanisms can also have indirect effects on system integrity by facilitating interactions among components. We explore the indirect role that conflict management mechanisms play in the maintenance of social system robustness, using a perturbation technique to 'knockout' components responsible for effective conflict management. We explore the effects of knockout on pigtailed macaque (Macaca nemestrina) social organization, using a captive group of 84 individuals. This system is ideal in addressing this question because there is heterogeneity in performance of conflict management. Consequently, conflict managers can be easily removed without disrupting other control structures. We find that powerful conflict managers are essential in maintaining social order for the benefit of all members of society. We show that knockout of components responsible for conflict management results in system destabilization by significantly increasing mean levels of conflict and aggression, decreasing socio-positive interaction and decreasing the operation of repair mechanisms. |
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Santa Fe Institute, NM 87501, USA. jflack@santafe.edu |
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0962-8452 |
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PMID:16024369 |
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no |
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Call Number |
refbase @ user @ |
Serial |
165 |
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Author |
Brosnan, S.F.; Schiff, H.C.; de Waal, F.B.M. |
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Title |
Tolerance for inequity may increase with social closeness in chimpanzees |
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Journal Article |
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Year |
2005 |
Publication |
Proceedings. Biological sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
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Volume |
272 |
Issue |
1560 |
Pages |
253-258 |
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Keywords |
Analysis of Variance; Animals; *Attitude; Group Processes; Pan troglodytes/*psychology; Reward; *Social Behavior; Socioeconomic Factors |
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Abstract |
Economic decision-making depends on our social environment. Humans tend to respond differently to inequity in close relationships, yet we know little about the potential for such variation in other species. We examine responses to inequity in several groups of chimpanzees (Pan troglodytes) in a paradigm similar to that used previously in capuchin monkeys (Cebus apella). We demonstrate that, like capuchin monkeys, chimpanzees show a response to inequity of rewards that is based upon the partner receiving the reward rather than the presence of the reward alone. However, we also found a great amount of variation between groups tested, indicating that chimpanzees, like people, respond to inequity in a variable manner, which we speculate could be caused by such variables as group size, the social closeness of the group (as reflected in length of time that the group has been together) and group-specific traditions. |
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Yerkes National Primate Research Center, Emory University, 954 North Gatewood Drive, Atlanta, GA 30329, USA. sbrosna@emory.edu |
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0962-8452 |
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PMID:15705549 |
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refbase @ user @ |
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169 |
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Fischer, J.; Cheney, D.L.; Seyfarth, R.M. |
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Title |
Development of infant baboons' responses to graded bark variants |
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Journal Article |
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Year |
2000 |
Publication |
Proceedings. Biological sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
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Volume |
267 |
Issue |
1459 |
Pages |
2317-2321 |
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Keywords |
*Animal Communication; Animals; Behavior, Animal; Female; Male; Models, Psychological; Papio/growth & development/*physiology; *Vocalization, Animal |
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Abstract |
We studied the development of infant baboons' (Papio cynocephalus ursinus) responses to conspecific 'barks' in a free-ranging population in the Okavango Delta, Botswana. These barks grade from tonal, harmonically rich calls into calls with a more noisy, harsh structure. Typically, tonal variants are given when the signaller is at risk of losing contact with the group or a particular individual ('contact barks'), whereas harsh variants are given in response to predators ('alarm barks'). We conducted focal observations and playback experiments in which we presented variants of barks recorded from resident adult females. By six months of age, infants reliably discriminated between typical alarm and contact barks and they responded more strongly to intermediate alarm calls than to typical contact barks. Infants of six months and older also recognized their mothers by voice. The ability to discriminate between different call variants developed with increasing age. At two and a half months of age, infants failed to respond at all, whereas at four months they responded irrespective of the call type that was presented. At six months, infants showed adult-like responses by responding strongly to alarm barks but ignoring contact barks. We concluded that infants gradually learn to attach the appropriate meaning to alarm and contact barks. |
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Department of Psychology, University of Pennsylvania, 3815 Walnut Street, Philadelphia, PA 19104, USA. fischerj@eva.mpg.de |
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0962-8452 |
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PMID:11413649 |
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no |
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Call Number |
refbase @ user @ |
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694 |
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Author |
Healy, S.D.; Braham, S.R.; Braithwaite, V.A. |
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Title |
Spatial working memory in rats: no differences between the sexes |
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Journal Article |
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Year |
1999 |
Publication |
Proceedings. Biological Sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
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Volume |
266 |
Issue |
1435 |
Pages |
2303-2308 |
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Keywords |
Animals; Estrus/metabolism; Female; Male; Memory/*physiology; Rats; Sex Factors; Swimming |
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In a number of mammalian species, males appear to have superior spatial abilities to females. The favoured explanations for this cognitive difference are hormonal, with higher testosterone levels in males than females leading to better spatial performance, and evolutionary, where sexual selection has favoured males with increased spatial abilities for either better navigational skills in hunting or to enable an increased territory size. However, an alternative explanation for this sex difference focuses on the role of varying levels of oestrogen in females in spatial cognition (the 'fertility and parental care' hypothesis). One possibility is that varying oestrogen levels result in variation in spatial learning and memory so that, when tested across the oestrous cycle, females perform as well as males on days of low oestrogen but more poorly on days of high oestrogen. If day in the oestrous cycle is not taken into account then, across an experiment, any sex differences found would always produce male superiority. We used a spatial working memory task in a Morris water maze to test the spatial learning and memory abilities of male and female rats. The rats were tested across a number of consecutive days during which the females went through four oestrous cycles. We found no overall sex differences in latencies to reach a submerged platform in a Morris water maze but, on the day of oestrus (low oestrogen), females took an extra swim to learn the platform's location (a 100% increase over the other days in the cycle). Female swim speed also varied across the oestrous cycle but females were no less active on the day of oestrus. These results oppose the predictions of the fertility and parental care hypothesis. |
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Address |
Department of Psychology, University of Newcastle, UK. s.healey@ed.ac.uk |
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0962-8452 |
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PMID:10629980 |
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Call Number |
Equine Behaviour @ team @ |
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2818 |
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Author |
Joffe, T.H.; Dunbar, R.I. |
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Title |
Visual and socio-cognitive information processing in primate brain evolution |
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Journal Article |
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Year |
1997 |
Publication |
Proceedings. Biological Sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
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Volume |
264 |
Issue |
1386 |
Pages |
1303-1307 |
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Keywords |
Animals; Brain/anatomy & histology/*physiology; Cognition/physiology; *Evolution; Geniculate Bodies/anatomy & histology/physiology; Humans; Mental Processes/physiology; Neocortex/physiology; Primates/anatomy & histology/*physiology/*psychology; *Social Behavior; Visual Cortex/anatomy & histology/physiology |
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Abstract |
Social group size has been shown to correlate with neocortex size in primates. Here we use comparative analyses to show that social group size is independently correlated with the size of non-V1 neocortical areas, but not with other more proximate components of the visual system or with brain systems associated with emotional cueing (e.g. the amygdala). We argue that visual brain components serve as a social information 'input device' for socio-visual stimuli such as facial expressions, bodily gestures and visual status markers, while the non-visual neocortex serves as a 'processing device' whereby these social cues are encoded, interpreted and associated with stored information. However, the second appears to have greater overall importance because the size of the V1 visual area appears to reach an asymptotic size beyond which visual acuity and pattern recognition may not improve significantly. This is especially true of the great ape clade (including humans), that is known to use more sophisticated social cognitive strategies. |
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School of Life Sciences, University of Liverpool, UK |
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0962-8452 |
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PMID:9332015 |
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no |
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Serial |
2095 |
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Author |
Guo, G.L.; Moffit, J.S.; Nicol, C.J.; Ward, J.M.; Aleksunes, L.A.; Slitt, A.L.; Kliewer, S.A.; Manautou, J.E.; Gonzalez, F.J. |
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Title |
Enhanced acetaminophen toxicity by activation of the pregnane X receptor |
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Journal Article |
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Year |
2004 |
Publication |
Toxicological sciences : an official journal of the Society of Toxicology |
Abbreviated Journal |
Toxicol Sci |
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Volume |
82 |
Issue |
2 |
Pages |
374-380 |
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Keywords |
Acetaminophen/pharmacokinetics/*toxicity; Analgesics, Non-Narcotic/pharmacokinetics/*toxicity; Animals; Aryl Hydrocarbon Hydroxylases/biosynthesis; Biotransformation; Blotting, Northern; Chromatography, High Pressure Liquid; Cytochrome P-450 CYP3A; Membrane Proteins; Mice; Mice, Knockout; Oxidoreductases, N-Demethylating/biosynthesis; Pregnenolone Carbonitrile/pharmacology; Receptors, Cytoplasmic and Nuclear/*drug effects; Receptors, Steroid/*drug effects; Sulfhydryl Compounds/metabolism |
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Abstract |
The pregnane X receptor (PXR) is a ligand-activated transcription factor and member of the nuclear receptor superfamily. Activation of PXR represents an important mechanism for the induction of cytochrome P450 3A (CYP3A) enzymes that can convert acetaminophen (APAP) to its toxic intermediate metabolite, N-acetyl-p-benzoquinone imine (NAPQI). Therefore, it was hypothesized that activation of PXR plays a major role in APAP-induced hepatotoxicity. Pretreatment with the PXR activator, pregnenolone 16alpha-carbonitrile (PCN), markedly enhanced APAP-induced hepatic injury, as revealed by increased serum ALT levels and hepatic centrilobular necrosis, in wild-type but not in PXR-null mice. Further analysis showed that following PCN treatment, PXR-null mice had lower CYP3A11 expression, decreased NAPQI formation, and increased maintenance of hepatic glutathione content compared to wild-type mice. Thus, these results suggest that PXR plays a critical role in APAP-induced hepatic toxicity, probably by inducing CYP3A11 expression and hence increasing bioactivation. |
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Laboratory of Metabolism, CCR, NCI, NIH, Bethesda, Maryland 20892, USA |
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1096-6080 |
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PMID:15456926 |
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no |
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Call Number |
refbase @ user @ |
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71 |
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Author |
Nicol, C.J.; Yoon, M.; Ward, J.M.; Yamashita, M.; Fukamachi, K.; Peters, J.M.; Gonzalez, F.J. |
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Title |
PPARgamma influences susceptibility to DMBA-induced mammary, ovarian and skin carcinogenesis |
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Journal Article |
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Year |
2004 |
Publication |
Carcinogenesis |
Abbreviated Journal |
Carcinogenesis |
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Volume |
25 |
Issue |
9 |
Pages |
1747-1755 |
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Keywords |
9,10-Dimethyl-1,2-benzanthracene/*toxicity; Animals; DNA Primers/chemistry; Disease Susceptibility; Female; Heterozygote; Humans; Mammary Neoplasms, Experimental/chemically induced/*pathology; Mice; Ovarian Neoplasms/chemically induced/*pathology; RNA, Messenger/genetics/metabolism; Receptors, Cytoplasmic and Nuclear/genetics/*physiology; Reverse Transcriptase Polymerase Chain Reaction; Skin Neoplasms/chemically induced/*pathology; Survival Rate; Transcription Factors/genetics/*physiology; Zinc Fingers |
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Abstract |
Peroxisome proliferator-activated receptor gamma (PPARgamma), a member of the nuclear receptor superfamily, plays a role in adipocyte differentiation, type II diabetes, macrophage response to inflammation and is suggested to influence carcinogen-induced colon cancer. Studies done in vitro and in vivo also revealed that PPARgamma ligands might promote differentiation and/or regression of mammary tumors. To directly evaluate the role of PPARgamma in mammary carcinogenesis, PPARgamma wild-type (+/+) or heterozygous (+/-) mice were administered 1 mg 7,12-dimethylbenz[a]anthracene (DMBA) by gavage once a week for 6 weeks and followed for a total of 25 weeks. Compared with congenic PPARgamma(+/+) littermate controls, PPARgamma(+/-) mice had early evidence for increased susceptibility to DMBA-mediated carcinogenesis based on a 1.6-fold increase in the percentage of mice with skin papillomas, as well as a 1.7-fold increase in the numbers of skin papillomas per mouse (P < 0.05). Similarly, PPARgamma(+/-) mice also had a 1.5-fold decreased survival rate (P = 0.059), and a 1.7-fold increased incidence of total tumors per mouse (P < 0.01). Moreover, PPARgamma(+/-) mice had an almost 3-fold increase in mammary adenocarcinomas (P < 0.05), an over 3-fold increase in ovarian granulosa cell carcinomas (P < 0.05), an over 3-fold increase in malignant tumors (P < 0.02) and a 4.6-fold increase in metastatic incidence. These results are the first to demonstrate an increased susceptibility in vivo of PPARgamma haploinsufficiency to DMBA-mediated carcinogenesis and suggest that PPARgamma may act as a tumor modifier of skin, ovarian and breast cancers. The data also support evidence suggesting a beneficial role for PPARgamma-specific ligands in the chemoprevention of mammary, ovarian and skin carcinogenesis. |
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Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA |
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0143-3334 |
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PMID:15073042 |
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no |
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Call Number |
refbase @ user @ |
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76 |
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Author |
Ward, M.P.; Ramsay, B.H.; Gallo, K. |
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Title |
Rural cases of equine West Nile virus encephalomyelitis and the normalized difference vegetation index |
Type |
Journal Article |
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Year |
2005 |
Publication |
Vector Borne and Zoonotic Diseases (Larchmont, N.Y.) |
Abbreviated Journal |
Vector Borne Zoonotic Dis |
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Volume |
5 |
Issue |
2 |
Pages |
181-188 |
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Keywords |
Animals; Biomass; Cluster Analysis; Disease Outbreaks/veterinary; Ecology; *Geographic Information Systems; Horse Diseases/*epidemiology; Horses; Indiana/epidemiology; Plants; Population Surveillance; Rural Health; Seasons; Topography, Medical/*methods; West Nile Fever/epidemiology/*veterinary |
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Abstract |
Data from an outbreak (August to October, 2002) of West Nile virus (WNV) encephalomyelitis in a population of horses located in northern Indiana was scanned for clusters in time and space. One significant (p = 0.04) cluster of case premises was detected, occurring between September 4 and 10 in the south-west part of the study area (85.70 degrees N, 45.50 degrees W). It included 10 case premises (3.67 case premises expected) within a radius of 2264 m. Image data were acquired by the Advanced Very High Resolution Radiometer (AVHRR) sensor onboard a National Oceanic and Atmospheric Administration polar-orbiting satellite. The Normalized Difference Vegetation Index (NDVI) was calculated from visible and near-infrared data of daily observations, which were composited to produce a weekly-1km(2) resolution raster image product. During the epidemic, a significant (p < 0.01) decrease (0.025 per week) in estimated NDVI was observed at all case and control premise sites. The median estimated NDVI (0.659) for case premises within the cluster identified was significantly (p < 0.01) greater than the median estimated NDVI for other case (0.571) and control (0.596) premises during the same period. The difference in median estimated NDVI for case premises within this cluster, compared to cases not included in this cluster, was greatest (5.3% and 5.1%, respectively) at 1 and 5 weeks preceding occurrence of the cluster. The NDVI may be useful for identifying foci of WNV transmission. |
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Department of Veterinary Pathobiology, Purdue University School of Veterinary Medicine, West Lafayette, Indiana, USA. mward@cvm.tamu.edu |
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1530-3667 |
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PMID:16011435 |
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Equine Behaviour @ team @ |
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2627 |
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Author |
Dubois, F.; Giraldeau, L.-A.; Hamilton, I.M.; Grant, J.W.A.; Lefebvre, L. |
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Title |
Distraction sneakers decrease the expected level of aggression within groups: a game-theoretic model |
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Journal Article |
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Year |
2004 |
Publication |
The American Naturalist |
Abbreviated Journal |
Am Nat |
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Volume |
164 |
Issue |
2 |
Pages |
E32-45 |
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*Aggression; Animals; Behavior, Animal/*physiology; Columbidae/*physiology; Competitive Behavior; Cooperative Behavior; *Game Theory; Hawks/*physiology; Models, Biological |
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Abstract |
Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp. |
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Address |
Departement des Sciences Biologiques, Universite du Quebec a Montreal, Case postale 8888 Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada. frede_dubois@yahoo.fr |
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1537-5323 |
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PMID:15278850 |
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no |
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Call Number |
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Serial |
2130 |
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Author |
Nicol, C.J.; Brown, S.N.; Glen, E.; Pope, S.J.; Short, F.J.; Warriss, P.D.; Zimmerman, P.H.; Wilkins, L.J. |
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Title |
Effects of stocking density, flock size and management on the welfare of laying hens in single-tier aviaries |
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Journal Article |
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Year |
2006 |
Publication |
British poultry science |
Abbreviated Journal |
Br Poult Sci |
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Volume |
47 |
Issue |
2 |
Pages |
135-146 |
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Animal Husbandry/*methods; *Animal Welfare; Animals; Body Constitution/*physiology; Chickens/*physiology; Crowding; Feathers; Female; *Housing, Animal/standards; Mortality; Organ Size; Oviposition/physiology; Population Density; Population Dynamics; Random Allocation |
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Abstract |
Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay. |
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School of Veterinary Science, University of Bristol, Langford House, Langford BS40 5DU and ADAS Gleadthorpe, Meden Vale, Mansfield, Notts NG20 9PF, England. c.j.nicol@bristol.ac.uk |
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English |
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0007-1668 |
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PMID:16641024 |
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refbase @ user @ |
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65 |
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