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Author Cameron, E.Z. doi  openurl
  Title Facultative adjustment of mammalian sex ratios in support of the Trivers-Willard hypothesis: evidence for a mechanism Type Journal Article
  Year 2004 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 271 Issue 1549 Pages 1723-1728  
  Keywords Age Factors; Animals; Body Constitution; *Evolution; Female; Glucose/metabolism/physiology; Litter Size; Male; Mammals/*physiology; *Models, Biological; Reproduction/physiology; Seasons; Sex Factors; *Sex Ratio; Time Factors  
  Abstract (up) Evolutionary theory predicts that mothers of different condition should adjust the birth sex ratio of their offspring in relation to future reproductive benefits. Published studies addressing variation in mammalian sex ratios have produced surprisingly contradictory results. Explaining the source of such variation has been a challenge for sex-ratio theory, not least because no mechanism for sex-ratio adjustment is known. I conducted a meta-analysis of previous mammalian sex-ratio studies to determine if there are any overall patterns in sex-ratio variation. The contradictory nature of previous results was confirmed. However, studies that investigated indices of condition around conception show almost unanimous support for the prediction that mothers in good condition bias their litters towards sons. Recent research on the role of glucose in reproductive functioning have shown that excess glucose favours the development of male blastocysts, providing a potential mechanism for sex-ratio variation in relation to maternal condition around conception. Furthermore, many of the conflicting results from studies on sex-ratio adjustment would be explained if glucose levels in utero during early cell division contributed to the determination of offspring sex ratios.  
  Address Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15306293 Approved no  
  Call Number refbase @ user @ Serial 413  
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Author Parr, L.A.; Winslow, J.T.; Hopkins, W.D.; de Waal, F.B. openurl 
  Title Recognizing facial cues: individual discrimination by chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta) Type Journal Article
  Year 2000 Publication Journal of comparative psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol  
  Volume 114 Issue 1 Pages 47-60  
  Keywords Animals; *Discrimination Learning; *Facial Expression; Female; Macaca mulatta/*psychology; Male; Mental Recall; Pan troglodytes/*psychology; Perceptual Masking; *Social Perception; Species Specificity  
  Abstract (up) Faces are one of the most salient classes of stimuli involved in social communication. Three experiments compared face-recognition abilities in chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta). In the face-matching task, the chimpanzees matched identical photographs of conspecifics' faces on Trial 1, and the rhesus monkeys did the same after 4 generalization trials. In the individual-recognition task, the chimpanzees matched 2 different photographs of the same individual after 2 trials, and the rhesus monkeys generalized in fewer than 6 trials. The feature-masking task showed that the eyes were the most important cue for individual recognition. Thus, chimpanzees and rhesus monkeys are able to use facial cues to discriminate unfamiliar conspecifics. Although the rhesus monkeys required many trials to learn the tasks, this is not evidence that faces are not as important social stimuli for them as for the chimpanzees.  
  Address Department of Psychology, Emory University. parr@rmy.emory.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0735-7036 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10739311 Approved no  
  Call Number refbase @ user @ Serial 191  
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Author Stock, K.F.; Hamann, H.; Distl, O. doi  openurl
  Title Factors associated with the prevalence of osseous fragments in the limb joints of Hanoverian Warmblood horses Type Journal Article
  Year 2006 Publication Veterinary Journal (London, England : 1997) Abbreviated Journal Vet J  
  Volume 171 Issue 1 Pages 147-156  
  Keywords Animals; Body Weight/physiology; Female; Horse Diseases/*epidemiology/genetics/*radiography; Horses; Joint Diseases/epidemiology/genetics/radiography/*veterinary; Male; Pedigree; Prevalence  
  Abstract (up) Factors associated with the prevalence of osseous fragments (OF) in fetlock and hock joints were investigated in a population of young Hanoverian Warmblood horses selected for sale at auction from 1991 to 1998. The study was based on results of a standardized radiological examination of 3127 horses. The prevalences of OF in the two joints were significantly dependent on the date, type and quality of the auction, the region of origin and on the anticipated suitability of the horses for dressage and/or show-jumping. The probability of finding OF increased with wither-height. Furthermore, there was a significant association of the individual sire with the prevalence of OF in both fetlock and hock joints, and of the maternal grandsire with the prevalence of OF in the hock joints. Consequently, both non-genetic and genetic parameters should be taken into account in order to reduce the prevalence of OF in young Warmblood riding horses.  
  Address Institute of Animal Breeding and Genetics, School of Veterinary Medicine Hannover, 30559 Hannover, Germany. kathrin-friederike.stock@tiho-hannover.de  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1090-0233 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16427591 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3712  
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Author Heitor, F.; do Mar Oom, M.; Vicente, L. doi  openurl
  Title Social relationships in a herd of Sorraia horses Part I. Correlates of social dominance and contexts of aggression Type Journal Article
  Year 2006 Publication Behavioural Processes Abbreviated Journal Behav. Process.  
  Volume 73 Issue 2 Pages 170-177  
  Keywords Age Factors; *Aggression; Animals; Female; *Hierarchy, Social; Horses/*psychology; Male; Sex Factors; *Social Dominance; *Social Environment; Statistics, Nonparametric  
  Abstract (up) Factors related to dominance rank and the functions of aggression were studied in a herd of Sorraia horses, Equus caballus, under extensive management. Subjects were 10 adult mares 5-18 years old and a stallion introduced into the group for breeding. Dominance relationships among mares were clear, irrespective of rank difference, and remained stable after introduction of the stallion. The dominance hierarchy was significantly linear and rank was positively correlated with age and total aggressiveness. Higher-ranking mares received lower frequency and intensity of agonistic interactions. Nevertheless, higher-ranking dominants were not more likely to elicit submission from their subordinates than lower-ranking dominants. Neither close-ranking mares nor mares with less clear dominance relationships were more aggressive towards each other. Agonistic interactions seemed to be used more importantly in regulation of space than to obtain access to food or to reassert dominance relationships. Contexts of aggression were related to mare rank. The results suggest that dominance relationships based on age as a conventional criterion were established to reduce aggressiveness in a herd where the costs of aggression are likely to outweigh the benefits.  
  Address Centro de Biologia Ambiental, Faculdade de Ciencias da Universidade de Lisboa, Campo Grande, Edificio C2, 1749-016 Lisboa, Portugal  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0376-6357 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16815645 Approved no  
  Call Number refbase @ user @ Serial 292  
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Author Schwarzenberger, F.; Mostl, E.; Bamberg, E.; Pammer, J.; Schmehlik, O. openurl 
  Title Concentrations of progestagens and oestrogens in the faeces of pregnant Lipizzan, trotter and thoroughbred mares Type Journal Article
  Year 1991 Publication Journal of reproduction and fertility. Supplement Abbreviated Journal J Reprod Fertil Suppl  
  Volume 44 Issue Pages 489-499  
  Keywords Animals; Estrogens/*analysis; Feces/*chemistry; Female; Gestational Age; Horses/*metabolism; Immunoenzyme Techniques; Labor, Obstetric; Pregnancy; Pregnancy, Animal/*metabolism; Pregnenes/analysis; Progestins/*analysis  
  Abstract (up) Faecal samples were collected at weekly intervals from pregnant Lipizzan mares during Weeks 7-16 following mating and from Lipizzan, Trotter and Thoroughbred mares during the last 3 months of gestation. After parturition, samples were taken daily from the Thoroughbred mares for another 6 days. Non-pregnant mares served as controls. The concentrations of unconjugated oestrogens (Eg), 20 alpha-OH-progestagens (20 alpha-G) and 20 beta-OH-progestagens (20 beta-G) were measured by enzyme immunoassay. In the faeces of Lipizzan mares, immunoreactive progestagens were significantly (P less than 0.01) elevated above the levels in non-pregnant mares by Week 11, and Eg by Week 13 of pregnancy onwards. During the last 3 months of gestation, concentrations of Eg were significantly higher in Trotter mares than in Lipizzan and Thoroughbred mares. Concentrations of 20 alpha-G and 20 beta-G increased to maximal values in the last month of gestation. There was no significant difference among the 3 breeds with respect to 20 alpha-G but, during the 10 weeks before parturition, concentrations of 20 beta-G in the Lipizzan mares were significantly lower (P less than 0.05) than those in the Thoroughbred mares. They were also significantly lower than those of the Trotter mares during the last 4 weeks of gestation. After parturition, the concentrations of Eg and progestagens had declined to baseline values by Days 3 and 4 respectively. From these results we conclude that high concentrations of progestagens with 20 alpha- and 20 beta-hydroxyl groups are present in the faeces of pregnant mares, especially during the last month of gestation.  
  Address Institut fur Biochemie, Veterinary Medical University, Vienna, Austria  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0449-3087 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1795293 Approved no  
  Call Number refbase @ user @ Serial 322  
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Author Hill, S.E.; Ryan, M.J. doi  openurl
  Title The role of model female quality in the mate choice copying behaviour of sailfin mollies Type Journal Article
  Year 2006 Publication Biology letters Abbreviated Journal Biol Lett  
  Volume 2 Issue 2 Pages 203-205  
  Keywords Animals; *Choice Behavior; Female; Male; *Mating Preference, Animal; Poecilia/*physiology  
  Abstract (up) Female mate choice copying is a socially mediated mate choice behaviour, in which a male's attractiveness to females increases if he was previously chosen by another female as a mate. Although copying has been demonstrated in numerous species, little is known about the specific benefits it confers to copying females. Here we demonstrate that the mate choice behaviour of female sailfin mollies (Poecilia latipinna) is influenced by the phenotypic quality of model females with whom males are observed consorting. Test females choosing between two males of similar body length were found to significantly increase time spent with previously non-preferred males after having observed them with a relatively high-quality female. Conversely, females were found to significantly decrease time spent with previously preferred males after having observed them with a relatively low-quality female. Female mate choice copying might be maintained by selection based on the heuristic value it provides females choosing between males whose quality differences are not easily distinguishable.  
  Address University of Texas at Austin, Department of Psychology, 1 University Station A8000, Austin, TX 78712, USA. sehill@mail.utexas.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1744-9561 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17148362 Approved no  
  Call Number Serial 1820  
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Author Brazas, M.L.; Shimizu, T. doi  openurl
  Title Significance of visual cues in choice behavior in the female zebra finch (Taeniopygia guttata castanotis) Type Journal Article
  Year 2002 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 5 Issue 2 Pages 91-95  
  Keywords Animals; Auditory Perception; Female; Male; *Sexual Behavior, Animal; Social Behavior; *Songbirds; *Visual Perception; Vocalization, Animal  
  Abstract (up) Female zebra finches show a preference for male zebra finches over heterospecific males based solely on the auditory cues of males, such as songs. The present study was designed to investigate whether females show a similar preference for male zebra finches based solely on visual cues. Using a Y-maze apparatus, social preference of female zebra finches was studied between male zebra finches and male Bengalese finches in three experiments. In experiment 1, where female zebra finches could see and hear live male zebra finches and male Bengalese finches, the females preferred to associate with the male zebra finches. In experiment 2, using a sound-attenuated experimental apparatus, subjects could see, but not hear, male zebra finches and male Bengalese finches. The subjects did not show a significant preference for associating with zebra finches. In experiment 3, as in experiment 2, females could see live male zebra finches and male Bengalese finches in the sound-attenuated chambers. However, in experiment 3, the subjects also heard prerecorded auditory cues (i.e., songs and calls) of male zebra finches, which were presented simultaneously in both arms of the maze. Although the females could not use the auditory cues to identify the location of the male zebra finches, they preferred to associate with the male zebra finches rather than the male Bengalese finches. These results suggest that visual cues alone were effective in initiating choice behaviors by females and that auditory cues facilitate such visually based choice behaviors.  
  Address Department of Psychology, University of South Florida, PCD4118G, 4202 East Fowler Avenue, Tampa, FL 33620, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12150041 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2603  
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Author Santos, L.R.; Miller, C.T.; Hauser, M.D. doi  openurl
  Title Representing tools: how two non-human primate species distinguish between the functionally relevant and irrelevant features of a tool Type Journal Article
  Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 6 Issue 4 Pages 269-281  
  Keywords Animals; *Discrimination Learning; Female; Form Perception/*physiology; Habituation, Psychophysiologic/*physiology; Imitative Behavior; Macaca mulatta/*growth & development/*psychology; Male; Motor Skills; Practice (Psychology); Saguinus/*growth & development/*psychology; Species Specificity  
  Abstract (up) Few studies have examined whether non-human tool-users understand the properties that are relevant for a tool's function. We tested cotton-top tamarins (Saguinus oedipus) and rhesus macaques (Macaca mulatta) on an expectancy violation procedure designed to assess whether these species make distinctions between the functionally relevant and irrelevant features of a tool. Subjects watched an experimenter use a tool to push a grape down a ramp, and then were presented with different displays in which the features of the original tool (shape, color, orientation) were selectively varied. Results indicated that both species looked longer when a newly shaped stick acted on the grape than when a newly colored stick performed the same action, suggesting that both species perceive shape as a more salient transformation than color. In contrast, tamarins, but not rhesus, attended to changes in the tool's orientation. We propose that some non-human primates begin with a predisposition to attend to a tool's shape and, with sufficient experience, develop a more sophisticated understanding of the features that are functionally relevant to tools.  
  Address Department of Psychology, Harvard University, Cambridge, MA 02138, USA. laurie.santos@yale.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12736800 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2570  
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Author Lucas, Z.; Raeside, J.I.; Betteridge, K.J. openurl 
  Title Non-invasive assessment of the incidences of pregnancy and pregnancy loss in the feral horses of Sable Island Type Journal Article
  Year 1991 Publication Journal of Reproduction and Fertility. Supplement Abbreviated Journal J Reprod Fertil Suppl  
  Volume 44 Issue Pages 479-488  
  Keywords Abortion, Veterinary/*epidemiology; Animals; Animals, Wild/*physiology; Atlantic Islands; Estrogens/analysis; Feces/chemistry; Female; Fertilization; Gestational Age; Horse Diseases/*epidemiology; Horses; Incidence; Pregnancy; *Pregnancy, Animal  
  Abstract (up) Field observations of 400 totally unmanaged feral horses on Sable Island, Nova Scotia, were complemented by oestrogen determinations in faecal samples from 154 identified females over a 4-year period (454 mare-years). Of mares that were sampled throughout the year and subsequently produced foals, 92.1% exhibited elevated faecal oestrogens between 15 October and 30 March. The results confirm that faecal oestrogens are a useful indicator of pregnancy after approximately 120 days gestation. Distribution of foaling resembled that seen in other feral populations, with 95% of births occurring from April through July. The foaling rate for mares aged 3 years or older was 62.0%, with 50.7% of mares foaling in 3 or 4 years. Foaling rates were low (4.1%) in mares bred as yearlings and rose with age to 70.8% in those bred as 4-year-olds. Fetal loss after Day 120 was deduced from faecal oestrogens to be 26.0% overall, with marked variation from year to year (9.6-37.3%) and with age (70.0% in those bred as yearlings, decreasing to 5.6% in those bred as 4-year-olds). Of 58 mares aged 2 years or older that were sampled every year, about half (49.6%) the barren years were attributable to fetal loss after 120 days gestation. All mares conceived in at least 2 of the 4 years, suggesting that pregnancy loss, even after Day 120, is as important as failure to conceive in causing barren years.  
  Address Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Canada  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0449-3087 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1795292 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2247  
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Author Lyda, R.O.; Hall, J.R.; Kirkpatrick, J.F. openurl 
  Title A comparison of Freund's Complete and Freund's Modified Adjuvants used with a contraceptive vaccine in wild horses (Equus caballus) Type Journal Article
  Year 2005 Publication Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians Abbreviated Journal J Zoo Wildl Med  
  Volume 36 Issue 4 Pages 610-616  
  Keywords Animals; Antibody Formation; Contraception, Immunologic/*veterinary; Estrus/drug effects; Female; Freund's Adjuvant/administration & dosage/adverse effects/*immunology; Horses/immunology/*physiology; *Vaccines, Contraceptive; Zona Pellucida/*immunology  
  Abstract (up) Fifteen captive wild mares (Equus caballus) were treated with porcine zona pellucida contraceptive vaccine and either Freund's Complete Adjuvant (n = 7) or Freund's Modified Adjuvant (n = 8). All mares received a booster inoculation of porcine zona pellucida plus Freund's Incomplete Adjuvant a month later. Anti-porcine zona pellucida antibodies were measured over 10 mo following the initial inoculation. There were no significant differences in antibody titers at any point during the 10 mo, and seven of the eight mares in the Freund's Modified Adjuvant group were above the 60% level at the end of the study, which is considered to be the contraceptive threshold for horses. There were no significant differences in titers between pregnant and nonpregnant horses, nor was there a significant correlation between age and titers. One local injection site reaction occurred after booster treatment with Freund's Incomplete Adjuvant, and 11 healthy foals were born during the course of the study. These data suggest that Freund's Modified Adjuvant is an acceptable substitute for Freund's Complete Adjuvant in certain free-ranging and captive wildlife species.  
  Address Science and Conservation Center, 2100 South Shiloh Road, Billings, Montana 59106, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1042-7260 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17312717 Approved no  
  Call Number refbase @ user @ Serial 139  
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