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Author Witte, T.H.; Knill, K.; Wilson, A.M. doi  openurl
  Title Determination of peak vertical ground reaction force from duty factor in the horse (Equus caballus) Type Journal Article
  Year (up) 2004 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol  
  Volume 207 Issue Pt 21 Pages 3639-3648  
  Keywords *Acceleration; Animals; Biomechanics; Forelimb/physiology; *Gait; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Telemetry; Time Factors  
  Abstract Measurement of peak vertical ground reaction force (GRFz) from multiple limbs simultaneously during high-speed, over-ground locomotion would enhance our understanding of the locomotor mechanics of cursorial animals. Here, we evaluate the accuracy of predicting peak GRFz from duty factor (the proportion of the stride for which the limb is in contact with the ground). Foot-mounted uniaxial accelerometers, combined with UHF FM telemetry, are shown to be practical and accurate for the field measurement of stride timing variables, including duty factor. Direct comparison with the force plate produces a mean error of 2.3 ms and 3.5 ms for the timing of foot on and foot off, respectively, across all gaits. Predictions of peak GRFz from duty factor show mean errors (with positive values indicating an overestimate) of 0.8+/-0.04 N kg(-1) (13%; N=42; mean +/- S.E.M.) at walk, -0.3+/-0.06 N kg(-1) (3%; N=75) at trot, -2.3+/-0.27 N kg(-1) (16%; N=18) for the non-lead limb at canter and +2.1+/-0.7 N kg(-1) (19%; N=9) for the lead limb at canter. The substantial over- and underestimate seen at canter, in the lead and non-lead limbs, respectively, is attributed to the different functions performed by the two limbs in the asymmetrical gaits. The difference in load experienced by the lead and non-lead limbs decreased with increasing speed.  
  Address Structure and Motion Lab, The Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA, UK  
  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 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15371472 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3658  
Permanent link to this record
 

 
Author Hodgson, D.; Howe, S.; Jeffcott, L.; Reid, S.; Mellor, D.; Higgins, A. doi  openurl
  Title Effect of prolonged use of altrenogest on behaviour in mares Type
  Year (up) 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.
 
  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 Whiten, A.; Horner, V.; de Waal, F.B.M. doi  openurl
  Title Conformity to cultural norms of tool use in chimpanzees Type Journal Article
  Year (up) 2005 Publication Nature Abbreviated Journal Nature  
  Volume 437 Issue 7059 Pages 737-740  
  Keywords Aging/physiology; Animals; Culture; Feeding Behavior/physiology; Female; Pan troglodytes/*physiology/*psychology; *Social Conformity; Technology; Time Factors  
  Abstract Rich circumstantial evidence suggests that the extensive behavioural diversity recorded in wild great apes reflects a complexity of cultural variation unmatched by species other than our own. However, the capacity for cultural transmission assumed by this interpretation has remained difficult to test rigorously in the field, where the scope for controlled experimentation is limited. Here we show that experimentally introduced technologies will spread within different ape communities. Unobserved by group mates, we first trained a high-ranking female from each of two groups of captive chimpanzees to adopt one of two different tool-use techniques for obtaining food from the same 'Pan-pipe' apparatus, then re-introduced each female to her respective group. All but two of 32 chimpanzees mastered the new technique under the influence of their local expert, whereas none did so in a third population lacking an expert. Most chimpanzees adopted the method seeded in their group, and these traditions continued to diverge over time. A subset of chimpanzees that discovered the alternative method nevertheless went on to match the predominant approach of their companions, showing a conformity bias that is regarded as a hallmark of human culture.  
  Address Centre for Social Learning and Cognitive Evolution, School of Psychology, University of St Andrews, St Andrews, Fife, KY16 9JP, UK. a.whiten@st-and.ac.uk  
  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 1476-4687 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16113685 Approved no  
  Call Number refbase @ user @ Serial 163  
Permanent link to this record
 

 
Author Zentall, T.R.; Kaiser, D.H. doi  openurl
  Title Interval timing with gaps: gap ambiguity as an alternative to temporal decay Type Journal Article
  Year (up) 2005 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process  
  Volume 31 Issue 4 Pages 484-486  
  Keywords Animals; Behavior, Animal; Discrimination (Psychology)/*physiology; Memory/*physiology; Rats; Time Perception/*physiology  
  Abstract C. V. Buhusi, D. Perera, and W. H. Meck (2005) proposed a hypothesis of timing in rats to account for the results of experiments that have used the peak procedure with gaps. According to this hypothesis, the introduction of a gap causes the animal's memory for the pregap interval to passively decay (subjectively shorten) in direct proportion to the duration and salience of the gap. Thus, animals should pause with short, nonsalient gaps but should reset their clock with longer, salient gaps. The present authors suggest that the ambiguity of the gap (i.e., the similarity between the gap and the intertrial interval in both appearance and relative duration) causes the animal to actively reset the clock and prevents adequate assessments of the fate of timed intervals prior to the gap. Furthermore, when the intertrial interval is discriminable from the gap, the evidence suggests that timed intervals prior to the gap are not lost but are retained in memory.  
  Address Department of Psychology, University of Kentucky, Lexington, KY 40506, USA. zentall@uky.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 0097-7403 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16248734 Approved no  
  Call Number refbase @ user @ Serial 220  
Permanent link to this record
 

 
Author Zentall, T.R. doi  openurl
  Title Timing, memory for intervals, and memory for untimed stimuli: the role of instructional ambiguity Type Journal Article
  Year (up) 2005 Publication Behavioural processes Abbreviated Journal Behav. Process.  
  Volume 70 Issue 3 Pages 209-222  
  Keywords Animals; *Attention; Columbidae; *Discrimination Learning; *Memory, Short-Term; Practice (Psychology); Reinforcement Schedule; *Retention (Psychology); *Time Perception  
  Abstract Theories of animal timing have had to account for findings that the memory for the duration of a timed interval appears to be dramatically shorted within a short time of its termination. This finding has led to the subjective shortening hypothesis and it has been proposed to account for the poor memory that animals appear to have for the initial portion of a timed interval when a gap is inserted in the to-be-timed signal. It has also been proposed to account for the poor memory for a relatively long interval that has been discriminated from a shorter interval. I suggest here a simpler account in which ambiguity between the gap or retention interval and the intertrial interval results in resetting the clock, rather than forgetting the interval. The ambiguity hypothesis, together with a signal salience mechanism that determines how quickly the clock is reset at the start of the intertrial interval can account for the results of the reported timing experiments that have used the peak procedure. Furthermore, instructional ambiguity rather than memory loss may account for the results of many animal memory experiments that do not involve memory for time.  
  Address Department of Psychology, University of Kentucky, 202B Kastle Hall, Lexington, KY 40506-0044, USA. zentall@uky.edu  
  Corporate Author Thesis  
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  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:16095851 Approved no  
  Call Number refbase @ user @ Serial 222  
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Author Huebener, E. url  openurl
  Title Der Natur abgelauschte Erkenntnisse: Der Weg zum Balancesitz und zum Begreifen des Timers für Signale an das Pferd; Type Journal Article
  Year (up) 2005 Publication Tierärztliche Umschau Abbreviated Journal Tierärztl. Umschau  
  Volume 2 Issue Pages 90-99  
  Keywords Bewegungen des Pferdes – Fundament des Reiter-Sitzes – Timer für Signale an das Pferd – Reflexe – Kommunikation – Forschungsbedarf  
  Abstract Zusammenfassung

Mit dem Beitrag “Die Bewegungen von Pferderumpf und -rücken aus der Sicht des Reiters” (TU 59, 327-334, 2004) wurde um universitäre Forschung zur Ermittlung gemessener Werte für diese Begleiter der Fortbewegung geworben.

Die Entdeckung des Ranges der Rumpf-Rücken-Bewegungen für pferdgerechtes und kultiviertes, feinfühliges Reiten ist mit der Entwicklung des Balancesitzes und der Technik des vom Pferd Zeitvorgaben Empfangens und ihm Signale Sendens (Reiter sagen: des Fühlens und Einwirkens) eng verbunden. Ihre Geschichte läßt sich über viereinhalb Jahrhunderte verfolgen. Ein kurzer Abriß wird hier nachgeliefert.

Er mündet erneut in ein Plädoyer für interdisziplinäres universitäres Forschen, weil auch bei Sitz und Hilfengebung, weiteren Grundlagen des Reitens – im Interesse effektiveren Unterrichts an der Basis unseres “Sports” – dringender Klärungsbedarf besteht.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language German Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ user @ Serial 421  
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Author Hemelrijk, C.K.; Wantia, J. doi  openurl
  Title Individual variation by self-organisation Type Journal Article
  Year (up) 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  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  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 Piccione, G.; Caola, G.; Refinetti, R. doi  openurl
  Title Temporal relationships of 21 physiological variables in horse and sheep Type Journal Article
  Year (up) 2005 Publication Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology Abbreviated Journal Comp Biochem Physiol A Mol Integr Physiol  
  Volume 142 Issue 4 Pages 389-396  
  Keywords Animals; Behavior, Animal/physiology; Blood Glucose/physiology; Body Temperature/*physiology; Circadian Rhythm/*physiology; Female; Horses/*physiology; Melatonin/blood/*physiology; Motor Activity/*physiology; Rectum/physiology; Sheep/*physiology; Time Factors  
  Abstract Daily or circadian oscillation has been documented in a variety of physiological and behavioral processes. Although individual variables have been studied in great detail, very few studies have been conducted on the temporal relationships between the rhythms of different variables. It is not known whether the circadian pacemaker generates each and every rhythm individually or whether most rhythms are simply derived from a few clock-controlled rhythms. As a first step in elucidating this issue, 21 physiological variables were recorded simultaneously in horse and sheep. The results indicated that, in both species, different variables exhibit different degrees of daily rhythmicity and reach their daily peaks at different times of the day. The variables exhibiting strongest rhythmicity were locomotor activity, rectal temperature, and plasma concentrations of melatonin and glucose. Comparison of rhythmicity and acrophase in the various rhythms allowed inferences to be made about mechanisms of causation.  
  Address Dipartimento di Morfologia, Biochimica, Fisiologia e Produzioni Animali, Facolta di Medicina Veterinaria, Universita degli Studi di Messina, 98168 Messina, Italy  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1095-6433 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16290083 Approved no  
  Call Number Serial 1884  
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Author Macfadden, B.J. doi  openurl
  Title Evolution. Fossil horses--evidence for evolution Type Journal Article
  Year (up) 2005 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume 307 Issue 5716 Pages 1728-1730  
  Keywords Animals; Body Size; DNA, Mitochondrial; Diet; *Equidae/anatomy & histology/classification/genetics; *Evolution; Feeding Behavior; *Fossils; *Horses/anatomy & histology/classification/genetics; Paleodontology; Phylogeny; Time; Tooth/anatomy & histology  
  Abstract  
  Address Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA. bmacfadd@flmnh.ufl.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 1095-9203 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15774746 Approved no  
  Call Number Serial 1892  
Permanent link to this record
 

 
Author Bobbert, M.F.; Santamaria, S. doi  openurl
  Title Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping Type Journal Article
  Year (up) 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  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  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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