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| Author | Hodgson, D.; Howe, S.; Jeffcott, L.; Reid, S.; Mellor, D.; Higgins, A. | ||||
| Title | Effect of prolonged use of altrenogest on behaviour in mares | Type | |||
| Year | 2005 | Publication | Veterinary journal (London, England : 1997) | Abbreviated Journal | Vet J |
| Volume | 169 | Issue | 1 | Pages | 113-115 |
| Keywords | Administration, Oral; Anabolic Agents/adverse effects/*pharmacology; Animals; Behavior, Animal/*drug effects; Body Constitution/drug effects; Body Weight/drug effects; *Doping in Sports; Female; Horses/*physiology; Social Behavior; Social Dominance; Time Factors; Trenbolone/adverse effects/*analogs & derivatives/*pharmacology | ||||
Abstract  |
Erratum in: Vet J. 2005 May;169(3):321. Corrected and republished in: Vet J. 2005 May;169(3):322-5. Oral administration of altrenogest for oestrus suppression in competition horses is believed to be widespread in some equestrian disciplines, and can be administered continuously for several months during a competition season. To examine whether altrenogest has any anabolic or other potential performance enhancing properties that may give a horse an unfair advantage, we examined the effect of oral altrenogest (0.044 mg/kg), given daily for a period of eight weeks, on social hierarchy, activity budget, body-mass and body condition score of 12 sedentary mares. We concluded that prolonged oral administration of altrenogest at recommended dose rates to sedentary mares resulted in no effect on dominance hierarchies, body mass or condition score. |
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| Address | Faculty of Veterinary Science, University of Sydney, Private Mailbag 4, Narellan Delivery Centre, Narellan, NSW 2567, Australia. davidh@camden.usyd.edu.au | ||||
| 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:15683772 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 671 | ||
| Permanent link to this record | |||||
| Author | Schwartz, B.L.; Meissner, C.A.; Hoffman, M.; Evans, S.; Frazier, L.D. | ||||
| Title | Event memory and misinformation effects in a gorilla (Gorilla gorilla gorilla) | Type | Journal Article | ||
| Year | 2004 | Publication | Animal Cognition | Abbreviated Journal | Anim. Cogn. |
| Volume | 7 | Issue | 2 | Pages | 93-100 |
| Keywords | Animals; *Deception; *Discrimination Learning; Gorilla gorilla/*psychology; Male; *Pattern Recognition, Visual; Photography; *Recognition (Psychology) | ||||
| Abstract |
Event memory and misinformation effects were examined in an adult male gorilla ( Gorilla gorilla gorilla). The gorilla witnessed a series of unique events, involving a familiar person engaging in a novel behavior (experiment 1), a novel person engaging in a novel behavior (experiment 2), or the presentation of a novel object (experiment 3). Following a 5- to 10-min retention interval, a tester gave the gorilla three photographs mounted on wooden cards: a photograph depicting the correct person or object and two distractor photographs drawn from the same class. The gorilla responded by returning a photograph. If correct, he was reinforced with food. Across three experiments, the gorilla performed significantly above chance at recognizing the target photograph. In experiment 4, the gorilla showed at-chance performance when the event was followed by misinformation (a class-consistent, but incorrect photograph), but significantly above-chance performance when no misinformation occurred (either correct photograph or no photograph). Although the familiarity can account for these data, they are also consistent with an episodic-memory interpretation. | ||||
| Address | Florida International University, University Park, FL 33199, Miami, USA. schwartb@fiu.edu | ||||
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| 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:15069608 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2532 | ||
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| Author | Dugatkin, L.A.; Godin, J.G. | ||||
| Title | Reversal of female mate choice by copying in the guppy (Poecilia reticulata) | Type | Journal Article | ||
| Year | 1992 | Publication | Proceedings. Biological sciences / The Royal Society | Abbreviated Journal | Proc Biol Sci |
| Volume | 249 | Issue | 1325 | Pages | 179-184 |
| Keywords | Acclimatization; Animals; *Choice Behavior; Female; Male; Poecilia; *Sexual Behavior, Animal | ||||
| Abstract |
Ever since Fisher (1958) formalized models of sexual selection, female mate choice has been assumed to be a genetically determined trait. Females, however, may also use social cues to select mates. One such cue might be the mate choice of conspecifics. Here we report the first direct evidence that a female's preference for a particular male can in fact be reversed by social cues. In our experiments using the Trinidadian guppy (Poecilia reticulata), this reversal was mediated by mate-copying opportunities, such that a female (the 'focal' female) is given the opportunity to choose between two males, followed by a period in which she observes a second female (the 'model' female) displaying a preference for the male she herself did not prefer initially. When allowed to choose between the same males a second time, compared with control tests, a significant proportion of focal females reversed their mate choice and copied the preference of the model female. These results provide strong evidence for the role of non-genetic factors in sexual selection and underlie the need for new models of sexual selection that explicitly incorporate both genetic and cultural aspects of mate choice. | ||||
| Address | Department of Biology, Mount Allison University, Sackville, New Brunswick, Canada | ||||
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| 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:1360679 | Approved | no | ||
| Call Number | Serial | 1824 | |||
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| Author | Cameron, E.Z. | ||||
| 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 |
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 | ||||
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| 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 | Subiaul, F.; Cantlon, J.F.; Holloway, R.L.; Terrace, H.S. | ||||
| Title | Cognitive imitation in rhesus macaques | Type | Journal Article | ||
| Year | 2004 | Publication | Science (New York, N.Y.) | Abbreviated Journal | Science |
| Volume | 305 | Issue | 5682 | Pages | 407-410 |
| Keywords | Animals; *Cognition; *Imitative Behavior; *Learning; Macaca mulatta/*physiology/psychology; Male | ||||
| Abstract |
Experiments on imitation typically evaluate a student's ability to copy some feature of an expert's motor behavior. Here, we describe a type of observational learning in which a student copies a cognitive rule rather than a specific motor action. Two rhesus macaques were trained to respond, in a prescribed order, to different sets of photographs that were displayed on a touch-sensitive monitor. Because the position of the photographs varied randomly from trial to trial, sequences could not be learned by motor imitation. Both monkeys learned new sequences more rapidly after observing an expert execute those sequences than when they had to learn new sequences entirely by trial and error. | ||||
| Address | Department of Anthropology, Columbia University, New York, NY 10027, USA. subiaul@aol.com | ||||
| 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 | 1095-9203 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15256673 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2839 | ||
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| Author | Parr, L.A.; Winslow, J.T.; Hopkins, W.D.; de Waal, F.B. | ||||
| 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 |
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. | ||||
| 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 |
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. | ||||
| 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 |
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. | ||||
| 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 |
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 | ||||
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| 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. | ||||
| 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 |
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 | ||||
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| 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 | |||
| Permanent link to this record | |||||