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| Author | Seyfarth, R.M. | ||||
| Title | A model of social grooming among adult female monkeys | Type | Journal Article | ||
| Year | 1977 | Publication | Journal of Theoretical Biology | Abbreviated Journal | J. Theor. Biol. |
| Volume | 65 | Issue | 4 | Pages | 671-698 |
| Keywords | Animals; Behavior, Animal; Female; *Grooming; Haplorhini/*physiology; *Models, Biological; Reproduction; Social Dominance; Time Factors | ||||
| Abstract | Grooming networks among adult female monkeys exhibit two similar features across a number of different species. High-ranking animals receive more grooming than others, and the majority of grooming occurs between females of adjacent rank. A theoretical model which duplicates these features is presented, and the properties of the model are used to explain the possible causation and function of female grooming behaviour. The model illustrates how relatively simple principles governing the behaviour of individuals may be used to explain more complex aspects of the social structure of non-human primate groups. | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-5193 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:406485 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 5259 | ||
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| Author | Romano, N.; Vitale, F.; Alesi, D.R.; Bonura, F.; La Licata, R.; Intonazzo, V.; Dardanoni, G.; Mammina, C. | ||||
| Title | The changing pattern of human immunodeficiency virus type 1 infection in intravenous drug users. Results of a six-year seroprevalence study in Palermo, Italy | Type | Journal Article | ||
| Year | 1992 | Publication | American Journal of Epidemiology | Abbreviated Journal | Am J Epidemiol |
| Volume | 135 | Issue | 11 | Pages | 1189-1196 |
| Keywords | Acquired Immunodeficiency Syndrome/*epidemiology; Adolescent; Adult; Chi-Square Distribution; Cross-Sectional Studies; Female; HIV Antibodies/blood; HIV Infections/*epidemiology; HIV Seroprevalence/*trends; *Hiv-1; Hepatitis B Antibodies/blood; Hepatitis B Surface Antigens/blood; Heroin; Humans; Incidence; Italy/epidemiology; Logistic Models; Male; Multivariate Analysis; Odds Ratio; Prevalence; Risk Factors; Substance Abuse, Intravenous/*epidemiology; Time Factors | ||||
| Abstract | A cross-sectional seroepidemiologic study was carried out between 1985 and 1990 in 1,567 heterosexual intravenous drug users who had been seen at the AIDS Regional Reference Center in Palermo, Italy, to evaluate the rate of human immunodeficiency virus type 1 (HIV-1) seroprevalence in this group and its long-term trend. Sixty serum samples collected from drug users in 1980 and 1983, before the founding of the Center (1985), were tested as well. Some demographic and behavioral risk factors were studied in a subgroup of intravenous drug users enrolled in 1985, 1987, and 1990 for their possible association with HIV-1. These factors were also studied in relation to hepatitis B virus infection, since both viruses share the same modes of spread. These drug users had a higher prevalence of markers for hepatitis B virus than of HIV-1 antibodies, and the prevalence rates in sera collected declined over time for both infections. The presence of both antibodies to HIV-1 and markers for hepatitis B virus was independently associated with the age of the drug user, the duration of drug use, and the year of serum collection. Antibodies to HIV-1 were observed more frequently in females than in males. No relation was found between education or employment status and the presence of HIV-1 antibodies or hepatitis B virus markers. Although new HIV-1 infections still occur, the decline in seroprevalence observed at the end of the 1980s might be related to modifications in social behavior among newer drug users, partial exhaustion of the susceptible population, and increasing risk awareness in more experienced users. | ||||
| Address | Giuseppe D'Alessandro Department of Hygiene and Microbiology, School of Medicine, University of Palermo, Italy | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0002-9262 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:1626537 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 5258 | ||
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| Author | Rands, S.A.; Cowlishaw, G.; Pettifor, R.A.; Rowcliffe, J.M.; Johnstone, R.A. | ||||
| Title | Spontaneous emergence of leaders and followers in foraging pairs | Type | Journal Article | ||
| Year | 2003 | Publication | Nature | Abbreviated Journal | Nature |
| Volume | 423 | Issue | 6938 | Pages | 432-434 |
| Keywords | Animals; *Energy Metabolism; Food; *Food Chain; *Models, Biological; Motor Activity; *Social Behavior; Time Factors | ||||
| Abstract | Animals that forage socially often stand to gain from coordination of their behaviour. Yet it is not known how group members reach a consensus on the timing of foraging bouts. Here we demonstrate a simple process by which this may occur. We develop a state-dependent, dynamic game model of foraging by a pair of animals, in which each individual chooses between resting or foraging during a series of consecutive periods, so as to maximize its own individual chances of survival. We find that, if there is an advantage to foraging together, the equilibrium behaviour of both individuals becomes highly synchronized. As a result of this synchronization, differences in the energetic reserves of the two players spontaneously develop, leading them to adopt different behavioural roles. The individual with lower reserves emerges as the 'pace-maker' who determines when the pair should forage, providing a straightforward resolution to the problem of group coordination. Moreover, the strategy that gives rise to this behaviour can be implemented by a simple 'rule of thumb' that requires no detailed knowledge of the state of other individuals. | ||||
| Address | Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. s.rands@zoo.cam.ac.uk | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0028-0836 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:12761547 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 5138 | ||
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| Author | Bobbert, M.F.; Santamaria, S. | ||||
| Title | Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping | Type | Journal Article | ||
| Year | 2005 | Publication | The Journal of Experimental Biology | Abbreviated Journal | J Exp Biol |
| Volume | 208 | Issue | 2 | Pages | 249-260 |
| Keywords | Animals; Biomechanics; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology; Muscle, Skeletal/*physiology; Time Factors | ||||
| Abstract | The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the leg behaved as a linear spring. During the forelimb push, the total energy first decreased by 3.2 J kg(-1) and then increased again by 4.2 J kg(-1) to the end of the forelimb push. At the end of the forelimb push, the kinetic energy due to horizontal velocity of the centre of mass was 1.6 J kg(-1) less than at the start, while the effective energy (energy contributing to jump height) was 2.3 J kg(-1) greater. It was investigated to what extent these changes could involve passive spring-like behaviour of the forelimbs. The amount of energy stored and re-utilized in the distal tendons during the forelimb push was estimated to be on average 0.4 J kg(-1) in the trailing forelimb and 0.23 J kg(-1) in the leading forelimb. This means that a considerable amount of energy was first dissipated and subsequently regenerated by muscles, with triceps brachii probably being the most important contributor. During the hindlimb push, the muscles of the leg were primarily producing energy. The total increase in energy was 2.5 J kg(-1) and the peak power output amounted to 71 W kg(-1). | ||||
| Address | Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, van der Boechorstraat 9, NL-1081 BT Amsterdam, The Netherlands. MFBobbert@fbw.vu.nl | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-0949 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15634844 | Approved | no | ||
| Call Number | Serial | 1895 | |||
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| Author | Donnelly, J.; Phipps, L.P.; Watkins, K.L. | ||||
| Title | Evidence of maternal antibodies to Babesia equi and B caballi in foals of seropositive mares | Type | Journal Article | ||
| Year | 1982 | Publication | Equine Veterinary Journal | Abbreviated Journal | Equine Vet J |
| Volume | 14 | Issue | 2 | Pages | 126-128 |
| Keywords | Animals; Antibodies/*analysis; Babesia/*immunology; Complement Fixation Tests; Female; Horses/*immunology; Immunity, Maternally-Acquired; Male; Time Factors | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0425-1644 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:7084196 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2280 | ||
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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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| Language | English | Summary Language | Original Title | ||
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| ISSN | 0962-8452 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15306293 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 413 | ||
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| Author | Rapin, V.; Poncet, P.A.; Burger, D.; Mermod, C.; Richard, M.A. | ||||
| Title | [Measurement of the attention time in the horse] | Type | Journal Article | ||
| Year | 2007 | Publication | Schweizer Archiv fur Tierheilkunde | Abbreviated Journal | Schweiz Arch Tierheilkd |
| Volume | 149 | Issue | 2 | Pages | 77-83 |
| Keywords | Age Factors; Animals; *Attention/physiology; Conditioning, Operant; Cross-Over Studies; Female; Horses/*physiology; Learning/*physiology; Male; Memory/*physiology; Time Factors | ||||
| Abstract | A study carried out on 49 horses showed that it is possible to measure the attention time by operant conditioning. After teaching horses an instrumental task using a signal, we were then able to test their attention time by asking them to prolong it increasingly while setting success and failure criteria. Two tests were performed 3 weeks apart. The 2nd test was feasible without relearning, a proof of memory, and was repeatable, a proof of consistency in the attention time. A significant difference was observed between the 3 age groups. Young horses often performed very well during the 1st test but their attention dropped in the 2nd test while older horses were more stable with respect to attention and even increased it slightly. The study shows that there are individual differences but it was not possible to prove a significant influence of breed, gender and paternal influence. Consequently, learning appears to be one of the most interesting approaches for evaluating the attention of horses and for observing their behaviour. | ||||
| Address | Laboratoire d'Ecoethologie, Universite de Neuchatel, Suisse. veronique.rapin@unine.ch | ||||
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| Language | French | Summary Language | Original Title | Mesure de la duree d'attention chez le cheval | |
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| ISSN | 0036-7281 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:17343134 | Approved | no | ||
| Call Number | Serial | 1770 | |||
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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 | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1090-0233 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15683772 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 671 | ||
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| Author | Hemelrijk, C.K.; Wantia, J. | ||||
| Title | Individual variation by self-organisation | Type | Journal Article | ||
| Year | 2005 | Publication | Neuroscience and biobehavioral reviews | Abbreviated Journal | Neurosci Biobehav Rev |
| Volume | 29 | Issue | 1 | Pages | 125-136 |
| Keywords | Aggression; Animals; Behavior, Animal/*physiology; Competitive Behavior/*physiology; Female; Humans; *Individuality; Male; Models, Psychological; Sex Characteristics; *Social Dominance; Time Factors | ||||
| Abstract | In this paper, we show that differences in dominance and spatial centrality of individuals in a group may arise through self-organisation. Our instrument is a model, called DomWorld, that represents two traits that are often found in animals, namely grouping and competing. In this model individual differences grow under the following conditions: (1) when the intensity of aggression increases and grouping becomes denser, (2) when the degree of sexual dimorphism in fighting power increases. In this case the differences among females compared to males grow too, (3) when, upon encountering another individual, the tendency to attack is 'obligate' and not conditional, namely 'sensitive to risks'. Results resemble phenomena described for societies of primates, mice, birds and pigs. | ||||
| Address | Theoretical Biology, University of Groningen, NN Haren, The Netherlands. hemelrij@ifi.unizh.ch | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0149-7634 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15652260 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 443 | ||
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| Author | Reichmuth Kastak, C.; Schusterman, R.J. | ||||
| Title | Long-term memory for concepts in a California sea lion ( Zalophus californianus) | Type | Journal Article | ||
| Year | 2002 | Publication | Animal Cognition | Abbreviated Journal | Anim. Cogn. |
| Volume | 5 | Issue | 4 | Pages | 225-232 |
| Keywords | Animals; Concept Formation; Female; Memory/*physiology; Mental Processes; Sea Lions/physiology/*psychology; Time Factors | ||||
| Abstract | An adult California sea lion ( Zalophus californianus) with extensive experience in performing discrimination learning tasks was tested to evaluate her long-term memory for two previously learned concepts. An associative concept, that of equivalence classification, was retested after a retention interval of approximately 1 year. The sea lion had originally shown emergent equivalence classification with nonsimilarity-based classes of stimuli in a simple discrimination repeated-reversal procedure as well as in a matching-to-sample procedure. The 1-year memory test revealed no decrement in classification performance in either procedure. A relational concept, that of generalized identity matching, was retested after approximately 10 years. The sea lion had originally received trial-and-error exemplar training with identity matching-to-sample problems prior to transferring the concept to novel stimulus configurations. In the 10-year memory test, the sea lion immediately and reliably applied the previously established identity concept to familiar and novel sets of matching problems. These are the first reports of long-term conceptual memory in a nonprimate species. The experimental findings are consistent with a variety of observations of sea lions in natural settings, which indicate that natal sites, feeding areas, and individuals may be remembered over long periods of time. | ||||
| Address | Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA. coll@cats.ucsc.edu | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | 1435-9448 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:12461600 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2590 | ||
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