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Author Mottley, K.; Giraldeau, L.A. doi  openurl
  Title Experimental evidence that group foragers can converge on predicted producer-scrounger equilibria Type Journal Article
  Year 2000 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume 60 Issue 3 Pages 341-350  
  Keywords  
  Abstract When foraging together, animals are often observed to feed from food discoveries of others. The producer-scrounger (PS) game predicts how frequently this phenomenon of food parasitism should occur. The game assumes: (1) at any moment all individuals can unambiguously be categorized as either playing producer (searching for undiscovered food resources) or scrounger (searching for exploitation opportunities), and (2) the payoffs received from the scrounger tactic are negatively frequency dependent; a scrounger does better than a producer when the scrounger tactic is rare, but worse when it is common. No study to date has shown that the payoffs of producer and scrounger conform to the game's assumptions or that groups of foragers reach the predicted stable equilibrium frequency (SEF) of scrounger, whereby both tactics obtain the same payoff. The current study of three captive flocks of spice finches, Lonchura punctulata, provides the first test of the PS game using an apparatus in which both assumptions of the PS game are met. The payoffs to the scrounger, measured as feeding rate (seeds/s), were highly negatively frequency dependent on the frequency of scrounger. The feeding rate for scrounger declined linearly while the rate for producer either declined only slightly or not at all with increasing scrounger frequency. When given the opportunity to alternate between tactics, the birds changed their use of each, such that the group converged on the predicted SEF of scrounger after 5-8 days of testing. Individuals in this study, therefore, demonstrated sufficient plasticity in tactic use such that the flock foraged at the SEF of scrounger. Copyright 2000 The Association for the Study of Animal Behaviour.  
  Address Department of Biology, Concordia University  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-3472 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11007643 Approved no  
  Call Number Serial 2136  
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Author Blunden, A.S.; Smith, K.C.; Whitwell, K.E.; Dunn, K.A. doi  openurl
  Title Systemic infection by equid herpesvirus-1 in a Grevy's zebra stallion (Equus grevyi) with particular reference to genital pathology Type Journal Article
  Year 1998 Publication Journal of Comparative Pathology Abbreviated Journal J Comp Pathol  
  Volume 119 Issue 4 Pages 485-493  
  Keywords Animals; Animals, Zoo; Epididymis/pathology/virology; Equidae/*virology; Herpesviridae Infections/diagnosis/pathology/*veterinary; Herpesvirus 1, Equid/isolation & purification/*pathogenicity; Lymph Nodes/pathology/virology; Male; Nasal Mucosa/pathology/virology; Pulmonary Edema/pathology; Spleen/virology; Testis/*pathology/virology  
  Abstract A severe multi-systemic form of equid herpesvirus-1 infection is described in an adult zebra stallion. There was multifocal necrotizing rhinitis, marked hydrothorax and pulmonary oedema, with viral antigen expression in degenerating epithelial cells, local endothelial cells and intravascular leucocytes of the nasal mucosa and lung. Specific localization of EHV-1 infection was seen in the testes and epididymides, including infection of Leydig cells and germinal epithelium, which would have facilitated venereal shedding of virus in life. The case provided a unique opportunity to study hitherto undescribed aspects of the pathogenesis of naturally occurring EHV-1 infection in the male equine genital tract. Restriction digests of the isolate demonstrated a pattern similar to that of EHV-1 isolates previously recovered from aborted zebra and onager fetuses.  
  Address Animal Health Trust Centre for Preventive Medicine, Newmarket, Suffolk, UK  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9975 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:9839210 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2239  
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Author Rubin, L.; Oppegard, C.; Hindz, H.F. url  doi
openurl 
  Title The effect of varying the temporal distribution of conditioning trials on equine learning behavior Type Journal Article
  Year 1980 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.  
  Volume 50 Issue 6 Pages 1184-1187  
  Keywords Animals; Conditioning (Psychology); *Horses; *Learning  
  Abstract Two experiments were conducted to study the effect of varying the temporal distrbution of conditioning sessions on equine learning behavior. In the first experiment, 15 ponies were trained to clear a small hurdle in response to a buzzer in order to avoid a mild electric shock. Three treatments were used. One group received 10 learning trials daily, seven times a week; one group was trained in the same fashion two times a week and one group was trained once a week. The animals conditioned only once a week achieved a high level of performance in significantly fewer sessions than the ones conditioned seven times a week, although elapsed time from start of training to completion was two to three times greater for the former group. The twice-a-week group learned at an intermediate rate. In the second experiment, the ponies were rearranged into three new groups. They were taught to move backward a specific distance in response to a visual cue in order to avoid an electric shock. Again, one group was trained seven times a week, one group was trained two times and one group was trained once a week. As in the first experiment, the animals trained once a week achieved the learning criteria in significantly fewer sessions than those trained seven times a week, but, as in trial 1, elapsed time from start to finish was greater for them. The two times-a-week group learned at a rate in-between the rates of the other two groups.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8812 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:7400060 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3558  
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Author Rhodin, M.; Johnston, C.; Holm, K.R.; Wennerstrand, J.; Drevemo, S. openurl 
  Title The influence of head and neck position on kinematics of the back in riding horses at the walk and trot Type Journal Article
  Year 2005 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 37 Issue 1 Pages 7-11  
  Keywords Acceleration; Animals; Back/*physiology; Biomechanics; Exercise Test/veterinary; Female; Gait/*physiology; Head/*physiology; Horses/*physiology; Male; Movement/physiology; Neck/*physiology; Walking/physiology  
  Abstract REASONS FOR PERFORMING STUDY: A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively. OBJECTIVES: To evaluate the effect of head and neck position on the kinematics of the back in riding horses. METHODS: Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the position of skin-fixed markers recorded by infrared videocameras. RESULTS: Head and neck position influenced the movements of the back, especially at the walk. When the head was fixed in a high position at the walk, the flexion-extension movement and lateral bending of the lumbar back, as well as the axial rotation, were significantly reduced when compared to movements with the head free or in a low position. At walk, head and neck position also significantly influenced stride length, which was shortest with the head in a high position. At trot, the stride length was independent of head position. CONCLUSIONS: Restricting and restraining the position and movement of the head and neck alters the movement of the back and stride characteristics. With the head and neck in a high position stride length and flexion and extension of the caudal back were significantly reduced. POTENTIAL RELEVANCE: Use of side reins in training and rehabilitation programmes should be used with an understanding of the possible effects on the horse's back.  
  Address Department of Anatomy, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15651727 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3657  
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Author Gomez Alvarez, C.B.; Rhodin, M.; Bobber, M.F.; Meyer, H.; Weishaupt, M.A.; Johnston, C.; Van Weeren, P.R. openurl 
  Title The effect of head and neck position on the thoracolumbar kinematics in the unridden horse Type Journal Article
  Year 2006 Publication Equine Veterinary Journal. Supplement Abbreviated Journal Equine Vet J Suppl  
  Volume Issue 36 Pages 445-451  
  Keywords Animals; Biomechanics; Head/*physiology; Horses/*physiology; Lumbar Vertebrae/physiology; Male; Neck/*physiology; Physical Conditioning, Animal/physiology; Posture/*physiology; Sports; Thoracic Vertebrae/physiology; Weight-Bearing  
  Abstract REASONS FOR PERFORMING STUDY: In many equestrian activities a specific position of head and/or neck is required that is dissimilar to the natural position. There is controversy about the effects of these positions on locomotion pattern, but few quantitative data are available. OBJECTIVES: To quantify the effects of 5 different head and neck positions on thoracolumbar kinematics of the horse. METHODS: Kinematics of 7 high level dressage horses were measured walking and trotting on an instrumented treadmill with the head and neck in the following positions: HNP2 = neck raised, bridge of the nose in front of the vertical; HNP3 = as HNP2 with bridge of the nose behind the vertical; HNP4 = head and neck lowered, nose behind the vertical; HNP5 = head and neck in extreme high position; HNP6 = head and neck forward and downward. HNP1 was a speed-matched control (head and neck unrestrained). RESULTS: The head and neck positions affected only the flexion-extension motion. The positions in which the neck was extended (HNP2, 3, 5) increased extension in the anterior thoracic region, but increased flexion in the posterior thoracic and lumbar region. For HNP4 the pattern was the opposite. Positions 2, 3 and 5 reduced the flexion-extension range of motion (ROM) while HNP4 increased it. HNP5 was the only position that negatively affected intravertebral pattern symmetry and reduced hindlimb protraction. The stride length was significantly reduced at walk in positions 2, 3, 4 and 5. CONCLUSIONS: There is a significant influence of head/neck position on back kinematics. Elevated head and neck induce extension in the thoracic region and flexion in the lumbar region; besides reducing the sagittal range of motion. Lowered head and neck produces the opposite. A very high position of the head and neck seems to disturb normal kinematics. POTENTIAL RELEVANCE: This study provides quantitative data on the effect of head/neck positions on thoracolumbar motion and may help in discussions on the ethical acceptability of some training methods.  
  Address Department of Equine Sciences, Utrecht University, Yalelaan 12, 3584 CM Utrecht, The Netherlands  
  Corporate Author Thesis  
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  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17402464 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3702  
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Author Weishaupt, M.A.; Wiestner, T.; von Peinen, K.; Waldern, N.; Roepstorff, L.; van Weeren, R.; Meyer, H.; Johnston, C. openurl 
  Title Effect of head and neck position on vertical ground reaction forces and interlimb coordination in the dressage horse ridden at walk and trot on a treadmill Type Journal Article
  Year 2006 Publication Equine Veterinary Journal. Supplement Abbreviated Journal Equine Vet J Suppl  
  Volume Issue 36 Pages 387-392  
  Keywords Animals; Biomechanics; Exercise Test/instrumentation/methods/*veterinary; Forelimb/physiology; Gait; Head/physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male; Neck/physiology; Physical Conditioning, Animal/methods/*physiology; Posture; Statistics, Nonparametric; Walking/*physiology  
  Abstract REASONS FOR PERFORMING STUDY: Little is known in quantitative terms about the influence of different head-neck positions (HNPs) on the loading pattern of the locomotor apparatus. Therefore it is difficult to predict whether a specific riding technique is beneficial for the horse or if it may increase the risk for injury. OBJECTIVE: To improve the understanding of forelimb-hindlimb balance and its underlying temporal changes in relation to different head and neck positions. METHODS: Vertical ground reaction force and time parameters of each limb were measured in 7 high level dressage horses while being ridden at walk and trot on an instrumented treadmill in 6 predetermined HNPs: HNP1 – free, unrestrained with loose reins; HNP2 – neck raised, bridge of the nose in front of the vertical; HNP3 – neck raised, bridge of the nose behind the vertical; HNP4 – neck lowered and flexed, bridge of the nose considerably behind the vertical; HNP5 – neck extremely elevated and bridge of the nose considerably in front of the vertical; HNP6 – neck and head extended forward and downward. Positions were judged by a qualified dressage judge. HNPs were assessed by comparing the data to a velocity-matched reference HNP (HNP2). Differences were tested using paired t test or Wilcoxon signed rank test (P<0.05). RESULTS: At the walk, stride duration and overreach distance increased in HNP1, but decreased in HNP3 and HNP5. Stride impulse was shifted to the forehand in HNP1 and HNP6, but shifted to the hindquarters in HNP5. At the trot, stride duration increased in HNP4 and HNP5. Overreach distance was shorter in HNP4. Stride impulse shifted to the hindquarters in HNP5. In HNP1 peak forces decreased in the forelimbs; in HNP5 peak forces increased in fore- and hindlimbs. CONCLUSIONS: HNP5 had the biggest impact on limb timing and load distribution and behaved inversely to HNP1 and HNP6. Shortening of forelimb stance duration in HNP5 increased peak forces although the percentage of stride impulse carried by the forelimbs decreased. POTENTIAL RELEVANCE: An extremely high HNP affects functionality much more than an extremely low neck.  
  Address Equine Hospital, University of Zurich, CH-8057 Zurich, Switzerland  
  Corporate Author Thesis  
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  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17402453 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3704  
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Author Hagen, S.J.; Eaton, W.A. doi  openurl
  Title Two-state expansion and collapse of a polypeptide Type Journal Article
  Year 2000 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol  
  Volume 301 Issue 4 Pages 1019-1027  
  Keywords Animals; Computer Simulation; Cytochrome c Group/*chemistry/*metabolism; Horses; Kinetics; Lasers; Models, Chemical; Peptides/*chemistry/*metabolism; Protein Conformation; Protein Denaturation; *Protein Folding; Spectrometry, Fluorescence; Temperature; Thermodynamics  
  Abstract The initial phase of folding for many proteins is presumed to be the collapse of the polypeptide chain from expanded to compact, but still denatured, conformations. Theory and simulations suggest that this collapse may be a two-state transition, characterized by barrier-crossing kinetics, while the collapse of homopolymers is continuous and multi-phasic. We have used a laser temperature-jump with fluorescence spectroscopy to measure the complete time-course of the collapse of denatured cytochrome c with nanosecond time resolution. We find the process to be exponential in time and thermally activated, with an apparent activation energy approximately 9 k(B)T (after correction for solvent viscosity). These results indicate that polypeptide collapse is kinetically a two-state transition. Because of the observed free energy barrier, the time scale of polypeptide collapse is dramatically slower than is predicted by Langevin models for homopolymer collapse.  
  Address Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Building 5, Bethesda, MD, 20892-0520, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-2836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10966803 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3790  
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Author Henderson, A.J.Z. doi  openurl
  Title Don't fence me in: managing psychological well being for elite performance horses Type Journal Article
  Year 2007 Publication Journal of Applied Animal Welfare Science : JAAWS Abbreviated Journal J. Appl. Anim. Welf. Sci.  
  Volume 10 Issue 4 Pages 309-329  
  Keywords *Animal Husbandry; Animal Welfare; Animals; *Behavior, Animal; Horses/*psychology; *Physical Conditioning, Animal; *Stereotyped Behavior  
  Abstract This article posits that stereotypical behavior patterns and the overall psychological well being of today's performance horse could be substantially enhanced with care that acknowledges the relationship between domesticated horses and their forerunners. Feral horses typically roam in stable, social groups over large grazing territories, spending 16-20 hr per day foraging on mid- to poor-quality roughage. In contrast, today's elite show horses live in relatively small stalls, eat a limited-but rich-diet at specific feedings, and typically live in social isolation. Although the horse has been domesticated for more than 6000 years, there has been no selection for an equid who no longer requires an outlet for these natural behaviors. Using equine stereotypies as a welfare indicator, this researcher proposes that the psychological well being of today's performance horse is compromised. Furthermore, the article illustrates how minimal management changes can enhance horses' well being while still remaining compatible with the requirements of the sport-horse industry. The article discusses conclusions in terms of Fraser, Weary, Pajor, and Milligan's “integrative welfare model” (1997).  
  Address Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada. zamoyska@shaw.ca  
  Corporate Author Thesis  
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  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1088-8705 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17970632 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4363  
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Author Krueger, K. (ed) pdf  isbn
openurl 
  Title Proceedings of the International Equine Science Meeting 2008 Type Conference Volume
  Year 2008 Publication IESM 2008 Abbreviated Journal  
  Volume Issue Pages  
  Keywords Equine Ecology; Equine Sociality; Equine Learning; Equine Cognition; Equine Welfare  
  Abstract Target group: Biologists, Psychologists, Veterinarians and Professionals

Meeting target: Because the last international meeting on Equine Science took place a couple years ago, there is an urgent need for equine scientists to exchange scientific knowledge, coordinate research provide knowledge for practical application, and discus research results among themselves and with professionals who work with horses. Additionally, dialog concerning the coordination of the study “Equitation Science” in Europe is urgently needed. Coordination and cooperation shall arise from the meeting, enrich the research, and advance the application of scientific knowledge for the horses` welfare.
 
  Address  
  Corporate Author Thesis  
  Publisher Xenophon Verlag Place of Publication Wald Editor Krueger, K.  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-3-9808134-0-2 Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4508  
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Author Hostetter, A.B.; Cantero, M.; Hopkins, W.D. url  openurl
  Title Differential use of vocal and gestural communication by chimpanzees (Pan troglodytes) in response to the attentional status of a human (Homo sapiens) Type Journal Article
  Year 2001 Publication Journal of Comparative Psychology Abbreviated Journal J. Comp. Psychol.  
  Volume 115 Issue 4 Pages 337-343  
  Keywords Animals; *Attention; *Communication Methods, Total; Female; *Gestures; Humans; Male; Motivation; Pan troglodytes/*psychology; Social Environment; Species Specificity; *Vocalization, Animal  
  Abstract This study examined the communicative behavior of 49 captive chimpanzees (Pan troglodytes), particularly their use of vocalizations, manual gestures, and other auditory- or tactile-based behaviors as a means of gaining an inattentive audience's attention. A human (Homo sapiens) experimenter held a banana while oriented either toward or away from the chimpanzee. The chimpanzees' behavior was recorded for 60 s. Chimpanzees emitted vocalizations faster and were more likely to produce vocalizations as their 1st communicative behavior when a human was oriented away from them. Chimpanzees used manual gestures more frequently and faster when the human was oriented toward them. These results replicate the findings of earlier studies on chimpanzee gestural communication and provide new information about the intentional and functional use of their vocalizations.  
  Address Department of Psychology, Berry College, USA  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0735-7036 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11824896 Approved yes  
  Call Number Equine Behaviour @ team @ Serial 4970  
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