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Drevemo, S.; Fredricson, I.; Hjertén, G.; McMIKEN, D. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Early development of gait asymmetries in trotting Standardbred colts |
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Journal Article |
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Year |
1987 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine. Vet. J. |
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19 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
3 |
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189-191 |
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Summary Ten trotting Standardbred colts were recorded by high-speed cinematography at the ages of eight, 12 and 18 months. The horses were trotting on a treadmill operating at 4.0 m/secs. Five horses were subjected to a programme of intensified training from eight months of age, whereas the others were not trained and acted as controls. The films were analysed on a semi-automatic film-reading equipment and a number of variables used to demonstrate the gait symmetry were calculated and scaled by computer. Certain differences between left and right diagonal and contralateral pair of limbs, respectively, were noted, suggesting that laterality in horses may be inherited. The most pronounced systematic differences were found in 18-month old horses in the trained group. The results show the importance of careful gait examination and comprehensive coordination training at an early age. |
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American Medical Association (AMA) |
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0425-1644 |
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https://doi.org/10.1111/j.2042-3306.1987.tb01373.x |
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Equine Behaviour @ team @ |
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6702 |
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Burton, A.C.; Neilson, E.; Moreira, D.; Ladle, A.; Steenweg, R.; Fisher, J.T.; Bayne, E.; Boutin, S. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
REVIEW: Wildlife camera trapping: a review and recommendations for linking surveys to ecological processes |
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Journal Article |
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Year |
2015 |
Publication |
Journal of Applied Ecology |
Abbreviated Journal |
J Appl Ecol |
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52 |
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3 |
Pages |
675-685 |
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animal movement; camera trap; capture-recapture; density estimation; imperfect detection; mammal monitoring; occupancy model; relative abundance; sampling error; wildlife survey methodology |
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Summary Reliable assessment of animal populations is a long-standing challenge in wildlife ecology. Technological advances have led to widespread adoption of camera traps (CTs) to survey wildlife distribution, abundance and behaviour. As for any wildlife survey method, camera trapping must contend with sources of sampling error such as imperfect detection. Early applications focused on density estimation of naturally marked species, but there is growing interest in broad-scale CT surveys of unmarked populations and communities. Nevertheless, inferences based on detection indices are controversial, and the suitability of alternatives such as occupancy estimation is debatable. We reviewed 266 CT studies published between 2008 and 2013. We recorded study objectives and methodologies, evaluating the consistency of CT protocols and sampling designs, the extent to which CT surveys considered sampling error, and the linkages between analytical assumptions and species ecology. Nearly two-thirds of studies surveyed more than one species, and a majority used response variables that ignored imperfect detection (e.g. presence?absence, relative abundance). Many studies used opportunistic sampling and did not explicitly report details of sampling design and camera deployment that could affect conclusions. Most studies estimating density used capture?recapture methods on marked species, with spatially explicit methods becoming more prominent. Few studies estimated density for unmarked species, focusing instead on occupancy modelling or measures of relative abundance. While occupancy studies estimated detectability, most did not explicitly define key components of the modelling framework (e.g. a site) or discuss potential violations of model assumptions (e.g. site closure). Studies using relative abundance relied on assumptions of equal detectability, and most did not explicitly define expected relationships between measured responses and underlying ecological processes (e.g. animal abundance and movement). Synthesis and applications. The rapid adoption of camera traps represents an exciting transition in wildlife survey methodology. We remain optimistic about the technology's promise, but call for more explicit consideration of underlying processes of animal abundance, movement and detection by cameras, including more thorough reporting of methodological details and assumptions. Such transparency will facilitate efforts to evaluate and improve the reliability of camera trap surveys, ultimately leading to stronger inferences and helping to meet modern needs for effective ecological inquiry and biodiversity monitoring. |
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John Wiley & Sons, Ltd |
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0021-8901 |
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https://doi.org/10.1111/1365-2664.12432 |
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Equine Behaviour @ team @ |
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6703 |
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Gomez Alvarez, C.B.; Rhodin, M.; Bobber, M.F.; Meyer, H.; Weishaupt, M.A.; Johnston, C.; Van Weeren, P.R. |
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The effect of head and neck position on the thoracolumbar kinematics in the unridden horse |
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Journal Article |
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Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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36 |
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445-451 |
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Animals; Biomechanics; Head/*physiology; Horses/*physiology; Lumbar Vertebrae/physiology; Male; Neck/*physiology; Physical Conditioning, Animal/physiology; Posture/*physiology; Sports; Thoracic Vertebrae/physiology; Weight-Bearing |
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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. |
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Department of Equine Sciences, Utrecht University, Yalelaan 12, 3584 CM Utrecht, The Netherlands |
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PMID:17402464 |
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Equine Behaviour @ team @ |
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3702 |
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Weishaupt, M.A.; Wiestner, T.; von Peinen, K.; Waldern, N.; Roepstorff, L.; van Weeren, R.; Meyer, H.; Johnston, C. |
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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 |
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Journal Article |
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Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
36 |
Pages |
387-392 |
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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 |
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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. |
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Equine Hospital, University of Zurich, CH-8057 Zurich, Switzerland |
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PMID:17402453 |
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Equine Behaviour @ team @ |
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3704 |
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Author |
Zajonc, R.B. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Social Facilitation |
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Journal Article |
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Year |
1965 |
Publication |
Science |
Abbreviated Journal |
Science |
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149 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
3681 |
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269-274 |
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Abstract |
300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf |
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Equine Behaviour @ team @ |
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6565 |
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Author |
Morand-Ferron, J.; Quinn, J.L. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Larger groups of passerines are more efficient problem solvers in the wild |
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Journal Article |
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2011 |
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Proceedings of the National Academy of Sciences of the United States of America |
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Proc Natl Acad Sci USA |
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108 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
38 |
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15898-15903 |
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Group living commonly helps organisms face challenging environmental conditions. Although a known phenomenon in humans, recent findings suggest that a benefit of group living in animals generally might be increased innovative problem-solving efficiency. This benefit has never been demonstrated in a natural context, however, and the mechanisms underlying improved efficiency are largely unknown. We examined the problem-solving performance of great and blue tits at automated devices and found that efficiency increased with flock size. This relationship held when restricting the analysis to naive individuals, demonstrating that larger groups increased innovation efficiency. In addition to this effect of naive flock size, the presence of at least one experienced bird increased the frequency of solving, and larger flocks were more likely to contain experienced birds. These findings provide empirical evidence for the “pool of competence” hypothesis in nonhuman animals. The probability of success also differed consistently between individuals, a necessary condition for the pool of competence hypothesis. Solvers had a higher probability of success when foraging with a larger number of companions and when using devices located near rather than further from protective tree cover, suggesting a role for reduced predation risk on problem-solving efficiency. In contrast to traditional group living theory, individuals joining larger flocks benefited from a higher seed intake, suggesting that group living facilitated exploitation of a novel food source through improved problem-solving efficiency. Together our results suggest that both ecological and social factors, through reduced predation risk and increased pool of competence, mediate innovation in natural populations. |
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Equine Behaviour @ team @ |
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6539 |
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Author |
John, E.R.; Chesler, P.; Bartlett, F.; Victor, I. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Observation Learning in Cats |
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1968 |
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Science |
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Science |
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159 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
3822 |
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1489-1491 |
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In two experiments cats acquired a stimulus-controlled approach or avoidance response by observational or conventional shaping procedures. Observer cats acquired the avoidance response (hurdle jumping in response to a buzzer stimulus) significantly faster and made fewer errors than cats that were conventionally trained. Observer cats acquired the approach response (lever pressing for food in response to a light stimulus) with significantly fewer errors than cats that were conventionally trained. In some cases, observer cats committed one or no errors while reaching criterion. |
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Equine Behaviour @ team @ |
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6422 |
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Author |
Zentall, T.R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Imitation: definitions, evidence, and mechanisms |
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Journal Article |
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Year |
2006 |
Publication |
Animal cognition |
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Anim. Cogn. |
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9 |
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4 |
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335-353 |
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Adaptation, Psychological; Animals; *Behavior, Animal; *Imitative Behavior; *Learning; Motivation; *Social Environment; Transfer (Psychology) |
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Imitation can be defined as the copying of behavior. To a biologist, interest in imitation is focused on its adaptive value for the survival of the organism, but to a psychologist, the mechanisms responsible for imitation are the most interesting. For psychologists, the most important cases of imitation are those that involve demonstrated behavior that the imitator cannot see when it performs the behavior (e.g., scratching one's head). Such examples of imitation are sometimes referred to as opaque imitation because they are difficult to account for without positing cognitive mechanisms, such as perspective taking, that most animals have not been acknowledged to have. The present review first identifies various forms of social influence and social learning that do not qualify as opaque imitation, including species-typical mechanisms (e.g., mimicry and contagion), motivational mechanisms (e.g., social facilitation, incentive motivation, transfer of fear), attentional mechanisms (e.g., local enhancement, stimulus enhancement), imprinting, following, observational conditioning, and learning how the environment works (affordance learning). It then presents evidence for different forms of opaque imitation in animals, and identifies characteristics of human imitation that have been proposed to distinguish it from animal imitation. Finally, it examines the role played in opaque imitation by demonstrator reinforcement and observer motivation. Although accounts of imitation have been proposed that vary in their level of analysis from neural to cognitive, at present no theory of imitation appears to be adequate to account for the varied results that have been found. |
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Department of Psychology, University of Kentucky, Lexington, KY 40506-0044, USA. Zentall@uky.edu |
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1435-9448 |
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PMID:17024510 |
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refbase @ user @ |
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217 |
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McCall, C.A.; Salters, M.A.; Simpson, S.M. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Relationship between number of conditioning trials per training session and avoidance learning in horses |
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Journal Article |
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1993 |
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Applied Animal Behaviour Science |
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Appl. Anim. Behav. Sci. |
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36 |
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4 |
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291-299 |
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Horse; Learning; Avoidance conditioning |
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Sixteen horses were used to determine if number of trials given per training session (5, 10, 15 or 20) affected learning performance in an avoidance conditioning task. The horse had to move from one side of a test pen to the other during an auditory cue presentation to avoid aversive stimulation. A pen 8 mx3.6 m, divided into two equal sections by a 13-cm diameter plastic pipe lying on the ground, was used as the test pen. Painted plywood panels were fastened to the fence in half the pen to help horses distinguish visually between the two parts. A 10-s auditory cue was used as a signal for horses to move from one side of the test pen to the other. A 20-s intertrial interval was used. Training sessions were conducted every third day. Each trial was recorded as an avoidance (the horse completed the task during auditory cue presentation and avoided aversive stimulus) or an error (the horse received aversive stimulus). After completing ten consecutive avoidances (criterion), the horse was removed from the study. Numbers of training sessions, trials, avoidances and errors until reaching criterion were recorded for each horse. Horses varied greatly within these variables with ranges of 3-18 sessions, 37-121 trials, 20-68 avoidances and 17-53 errors to criterion. No differences were detected (P>0.05) in the number of conditioning trials per training session (treatment) for the mean number of trials, avoidances or errors to criterion. Number of training sessions to criterion differed (P<0.01) among treatments, indicating that an optimum number of learning trials per training session might exist. Mean sessions to criterion for horses receiving 5, 10, 15 and 20 trials per session were 15.1+/-1.3, 5.8+/-1.1, 5.3+/-1.1 and 4.6+/-1.1, respectively. Regression analysis indicated that 16.2 trials per training session would minimize number of sessions to criterion. Although it is widely assumed that learning efficiency in horses is decreased when intense activity is concentrated into a small number of sessions, these results indicate that moderate repetition of training activities is needed for efficient learning. |
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Equine Behaviour @ team @ |
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3686 |
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Author |
Hagen, S.J.; Eaton, W.A. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Two-state expansion and collapse of a polypeptide |
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Journal Article |
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2000 |
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Journal of Molecular Biology |
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J Mol Biol |
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301 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
4 |
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1019-1027 |
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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 |
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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. |
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Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Building 5, Bethesda, MD, 20892-0520, USA |
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Series Issue |
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Edition |
|
|
|
ISSN |
0022-2836 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
PMID:10966803 |
Approved |
no |
|
|
Call Number |
Equine Behaviour @ team @ |
Serial |
3790 |
|
Permanent link to this record |