| Home | [1–10] << 11 12 13 14 15 16 17 18 19 >> |
|
| Records | |||||
|---|---|---|---|---|---|
Author  |
Austin, N.P.; Rogers, L.J. | ||||
| Title | Limb preferences and lateralization of aggression, reactivity and vigilance in feral horses, Equus caballus | Type | Journal Article | ||
| Year | 2012 | Publication | Animal Behaviour | Abbreviated Journal | Anim. Behav. |
| Volume | 83 | Issue | 1 | Pages | 239-247 |
| Keywords | aggression; behavioural asymmetry; Equus caballus; eye preference; feral horse; limb preference; reactivity; side bias | ||||
| Abstract | Observational field studies were conducted on two remote populations of feral horses in Australia to determine whether lateralization is a characteristic of Equus caballus as a species or results from handling by humans. Group 1 had been feral for two to five generations and Group 2 for 10–20 generations. In both groups, left-side biases were present during agonistic interactions and in reactivity and vigilance. Therefore, as in other vertebrates, the right hemisphere appears to be specialized to control agonistic behaviour and responses to potential threats. The leftwards bias was stronger in measures of behaviour involving more aggression and reactivity. Preferences to place one forelimb in front of the other during grazing were also determined. No population bias of forelimb preference was found, suggesting that such limb preferences present in domestic horses may be entrained. Since stronger individual limb preferences were found in immature than in adult feral horses, limb preference may be modified by maturation or experience in the natural habitat. Stronger limb preference was associated significantly with elevated attention to the environment but only in younger feral horses. No sex differences in lateralization were found. The findings are evidence that horses show visual lateralization, as in other vertebrates, not dependent on handling by humans. Limb preference during grazing, by contrast, does appear to depend on experience. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | 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 | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5651 | ||
| Permanent link to this record | |||||
| Author |
Austin, N.P.; Rogers, L.J. | ||||
| Title | Lateralization of agonistic and vigilance responses in Przewalski horses (Equus przewalskii) | Type | Journal Article | ||
| Year | 2014 | Publication | Applied Animal Behaviour Science | Abbreviated Journal | |
| Volume | 151 | Issue | Pages | 43-50 | |
| Keywords | Behavioural lateralization: Eye preference; Limb preference; Aggression; Vigilance; Reactivity; Przewalski horses | ||||
| Abstract | tEye and limb preferences were scored in the closest undomesticated relative of Equuscaballus using the same methods as used previously to study laterality in feral horses.Observations were made of 33 Przewalski horses (Equus ferus przewalskii) (male N = 20,female N = 13) living under natural social conditions on a large reserve in France. Signifi-cant left-eye/side biases were found in agonistic interactions within harem bands (M ± SEbias to left 58% ± 0.01 for threats, P < 0.001; 68% ± 0.05 for attacks; P < 0.001) and in stallionfights (threats, 52% ± 0.01 left, P < 0.001; attacks, 63% ± 0.02 left, P < 0.001): as many as 80%of the horses were significantly lateralized in attack responses within harem bands. Lat-erality of vigilance was measured as lifting up the head from grazing and turning it to theleft or right side: a directional bias to the left was found (M ± SE 53% ± 0.02 left, P < 0.001).Side bias in reactivity was calculated as the percent of head lifts above the level of thewithers on the left or right side and this was also left side biased (M ± SE 73% ± 0.03 left,P < 0.001). These results indicate right-hemisphere specialization for control of aggressionand responses to novelty. The left bias in attack scores within harem bands was strongerin males than females (P = 0.024) and in immature than adult horses (P = 0.032). Immaturehorses were also more strongly lateralized than adults in vigilance scores (P = 0.022), whichmay suggest that experience reduces these side biases. Our results show that Przewalskihorses exhibit left eye preferences, as do feral horses, and do so even more strongly thanferal horses. Considering feral and Przewalski horses together, we deduce that ancestralhorses had similar lateral biases. Also similar to feral horses, the Przewalski horses showedno significant forelimb preference at the group level or in the majority of horses at theindividual level, confirming the hypothesis that previously reported limb preferences indomestic breeds are entrained or generated by breed-specific selection. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0168-1591 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5768 | ||
| Permanent link to this record | |||||
| Author |
Albright, J.D.; Mohammed, H.O.; Heleski, C.R.; Wickens, C.L.; Houpt, K.A. | ||||
| Title | Crib-biting in US horses: Breed predispositions and owner perceptions of aetiology | Type | Journal Article | ||
| Year | 2009 | Publication | Equine Veterinary Journal | Abbreviated Journal | |
| Volume | 41 | Issue | 5 | Pages | 455-458 |
| Keywords | HORSE; BEHAVIOUR; CRIB-BITING; BREED PREVALENCE; LEARNING | ||||
| Abstract | Reasons for performing study: Crib-biting is an equine stereotypy that may result in diseases such as colic. Certain breeds and management factors have been associated. Objectives: To determine: breed prevalence of crib-biting in US horses; the likelihood that one horse learns to crib-bite from another; and owner perceptions of causal factors. Methods: An initial postal survey queried the number and breed of crib-biting horses and if a horse began after being exposed to a horse with this habit. In a follow-up survey, a volunteer subset of owners was asked the number of affected and nonaffected horses of each breed and the extent of conspecific contact. The likelihood of crib-biting given breed and extent of contact was quantified using odds ratio (OR) and significance of the association was assessed using the Chi-squared test. Results: Overall prevalence was 4.4%. Thoroughbreds were the breed most affected (13.3%). Approximately half of owners believed environmental factors predominantly cause the condition (54.4%) and crib-biting is learned by observation (48.8%). However, only 1.0% of horses became affected after being exposed to a crib-biter. The majority (86%) of horses was turned out in the same pasture with other horses and extent of contact with conspecifics was not statistically related to risk. Conclusion: This is the first study to report breed prevalence for crib-biting in US horses. Thoroughbreds were the breed more likely to be affected. More owners believed either environmental conditions were a predominant cause or a combination of genetic and environmental factors contributes to the behaviour. Only a small number of horses reportedly began to crib-bite after being exposed to an affected individual, but approximately half of owners considered it to be a learned behaviour; most owners did not isolate affected horses. Potential relevance: Genetic predisposition, not just intensive management conditions and surroundings, may be a factor in the high crib-biting prevalence in some breeds, and warrants further investigation. Little evidence exists to suggest horses learn the behaviour from other horses, and isolation may cause unnecessary stress. |
||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | 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 | Equine Behaviour @ team @ | Serial | 5010 | ||
| Permanent link to this record | |||||
| Author |
Ahrendt, L.P.; Labouriau, R.; Malmkvist, J.; Nicol, C.J.; Christensen, J.W. | ||||
| Title | Development of a standard test to assess negative reinforcement learning in horses | Type | Journal Article | ||
| Year | 2015 | Publication | Applied Animal Behaviour Science | Abbreviated Journal | Appl. Anim. Behav. Sci. |
| Volume | 169 | Issue | Pages | 38-42 | |
| Keywords | Algometry; Horse behaviour; Learning performance; Operant conditioning; Pressure-release; Horse training | ||||
| Abstract | Most horses are trained by negative reinforcement. Currently, however, no standardised test for evaluating horses' negative reinforcement learning ability is available. The aim of this study was to develop an objective test to investigate negative reinforcement learning in horses. Twenty-four Icelandic horses (3 years old) were included in this study. The horses were tested in a pressure-release task on three separate days with 10, 7 and 5 trials on each side, respectively. Each trial consisted of pressure being applied on the hindquarter with an algometer. The force of the pressure was increased until the horse moved laterally away from the point of pressure. There was a significant decrease in required force over trials on the first test day (P<0.001), but not the second and third day. The intercepts on days 2 and 3 differed significantly from day 1 (P<0.001), but not each other. Significantly stronger force was required on the right side compared to the left (P<0.001), but there was no difference between first and second side tested (P=0.56). Individual performance was evaluated by median-force and the change in force over trials on the first test day. These two measures may explain different characteristics of negative reinforcement learning. In conclusion, this study presents a novel, standardised test for evaluating negative reinforcement learning ability in horses. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0168-1591 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 6650 | ||
| Permanent link to this record | |||||
| Author |
Ahrendt, L.P.; Christensen, J.W.; Ladewig, J. | ||||
| Title | The ability of horses to learn an instrumental task through social observation | Type | Abstract | ||
| Year | 2012 | Publication | Applied Animal Behaviour Science | Abbreviated Journal | Appl. Anim. Behav. Sci. |
| Volume | 139 | Issue | 1 | Pages | 105-113 |
| Keywords | Horse; Social learning; Social interaction; Instrumental task; Investigative behaviour; Aggression | ||||
| Abstract | The ability of horses to learn through social observation may ease the implementation of new management systems, because the use of automatic feeders etc. by naive horses could be facilitated by observation of experienced horses. However, previous studies found no documentation for observational learning abilities in horses. This study aimed to investigate the ability of horses to learn an instrumental task from a familiar conspecific when social interaction was allowed during the demonstration. Two similar experiments were performed. In the first experiment, Observer horses (n=11) participated in ten successive demonstrations, where a trained Demonstrator opened an operant device by pushing a sliding lid aside with the muzzle in order to obtain a food reward. Immediately after the demonstrations the Observer horses were given the opportunity to operate the device alone. Control horses (n=11) were aware that the device contained food but were presented to the operant device without demonstration of the task. The learning criterion was at least two openings. Accomplishment of and latency to accomplish the learning criterion, and investigative behaviour towards the operant device were recorded. Five Observers and one Control, out of the eleven horses in each treatment group, accomplished the learning criterion. Even though this presents a high odds ratio (OR) in favour of the Observer treatment (OR=7.6), there was no significant difference between the treatment groups (P=0.15). Analysis of investigative behaviour showed, however, that the demonstrations increased the motivation of the Observer horses to investigate the device. Subsequently, a similar experiment was performed in a practical setting with 44 test horses (mixed age, gender and breed). We used the same operant device and the same number and type of demonstrations, although the horses were held on a loose rope to minimise aggression. In this second experiment, six of 23 Observer horses and five of 21 Control horses learned the instrumental task, representing no influence of the demonstration. Thus, this study did not demonstrate an ability of horses to learn an instrumental task through observation. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0168-1591 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ S0168-1591(12)00087-1 | Serial | 5773 | ||
| Permanent link to this record | |||||