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Anderson, M. K., Friend, T. H., Evans, J. W., & Bushong, D. M. (1999). Behavioral assessment of horses in therapeutic riding programs. Appl. Anim. Behav. Sci., 63(1), 11–24.
Abstract: A behavioral assessment of horses who were being used and not used in therapeutic riding programs was conducted to help determine useful methods of selecting horses for use in therapeutic riding programs. A total of 103 horses (76 horses from five therapeutic riding centers and 27 non-therapeutic riding horses from four sites) were used. Temperament survey for each horse were completed by three riding instructors at each therapeutic riding center or by the individual most knowledgeable about the horse at the other sites. Twenty personality traits from the survey were used to quantify temperament. Concentrations of plasma cortisol, norepinephrine and epinephrine were also measured in each horse. A reactivity test was then conducted which involved introducing three novel stimuli: a walking and vocalizing toy pig placed on a cardboard surface in front of the horse for 20 s; popping a balloon near the horse's flank area; and suddenly opening an umbrella and holding it open in front of the horse for 20 s. Reactions (expressions, vocalizations and movement) to each of the stimuli were scored and used to calculate an average reactivity score for each horse. The therapeutic riding instructors did not often agree on the temperament of their center's horses. The personality trait ratings made by the therapeutic riding instructors at each center were on average significantly correlated (P<0.01, r>0.52) for only 37.8% of the horses for any two instructors and 7.8% for three instructors. No significant correlations were found between temperament, reactivity, and the hormone concentrations (r<0.19), but regression analysis indicated a possibility of predicting temperament from the reactivity score and hormone concentrations (P<0.08). There was also a tendency for relationships between extremes in temperament (desirable vs. undesirable) and the hormone concentrations (P<0.09), and between extremes in reactivity (low vs. high) and the hormone concentrations (P=0.08). The difference in ratings among riding instructors indicates a need for more collaboration between instructors when evaluating horse temperament. This study also indicates that it was very difficult to objectively determine the suitability of horses for therapeutic riding programs regarding their temperament and reactivity, probably because other traits (e.g., smoothness of gait) are also considered very important.
Keywords: Horses; Therapeutic riding; Temperament; Cortisol; Catecholamines
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Feh, C. (1999). Alliances and reproductive success in Camargue stallions. Anim. Behav., 57(3), 705–713.
Abstract: A study of a herd of Camargue horsesEquus caballus, showed that while the majority of high-ranking stallions held single-male harems, some sons of low-ranking mares, being low ranking themselves, formed alliances that could last a lifetime. The two stallions were each other's closest associate and preferential grooming partner. Alliances were based on coalitions in which either both partners confronted an intruder synchronously or the dominant of the pair tended the female(s) while the subordinate simultaneously displayed towards the rival. Alliance partners were of similar age but were not more closely related to each other than to other stallions in the herd. Long-term paternity data revealed that subordinates sired close to a quarter of the foals born into the alliance group, and significantly more foals than low-ranking stallions in the herd adopting a `sneak'-mating strategy. The dominant appeared to benefit from the presence of his subordinate partner. Fights occurred all year round, and the subordinate stallion of each alliance pair fought outside competitors more than twice as often as the dominant. Forming short-term alliances before defending mares on their own may enhance long-term reproductive success for both partners. Other benefits to both partners include higher survivorship of their foals and increased access to proven reproductive mares. These results suggest that the relationship between alliance partners is based on mutualism, but several conditions for reciprocity seem to be fulfilled: the benefit to the dominant (assistance in fights), and the benefit to the subordinate (access to reproduction), are both costly to the other partner and delayed in time.
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Byrne, R. W. (1999). Imitation without intentionality. Using string parsing to copy the organization of behaviour. Anim. Cogn., 2(2), 63–72.
Abstract: A theory of imitation is proposed, string parsing, which separates the copying of behavioural organization by observation from an understanding of the cause of its effectiveness. In string parsing, recurring patterns in the visible stream of behaviour are detected and used to build a statistical sketch of the underlying hierarchical structure. This statistical sketch may in turn aid the subsequent comprehension of cause and effect. Three cases of social learning of relatively complex skills are examined, as potential cases of imitation by string parsing. Understanding the basic requirements for successful string parsing helps to resolve the conflict between mainly negative reports of imitation in experiments and more positive evidence from natural conditions. Since string parsing does not depend on comprehension of the intentions of other agents or the everyday physics of objects, separate tests of these abilities are needed even in animals shown to learn by imitation.
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Heiling, A. M., & Herberstein, M. E. (1999). The role of experience in web-building spiders (Araneidae). Anim. Cogn., 2(3), 171–177.
Abstract: A typical feature of vertical orb-webs is the 'top/bottom' asymmetry, where the lower web region is larger than the upper web region. This asymmetry may improve prey capture success, because, sitting in the hub of the web, a spider can reach prey entangled below the hub faster than prey entangled in the area above the hub. While web asymmetry is known to vary intraspecifically, we tested if this variation also exists at the individual level and whether it is the result of experience, using two orb-web spider species, Argiope keyserlingi and Larinioides sclopetarius. The results reveal that experienced web-building spiders constructed more asymmetric webs than conspecifics deprived of any prior building experience over a period of several months. Experienced individuals invested more silk material into the web region below the hub, which covered a larger area. Moreover, web asymmetry was also influenced by previous prey capture experiences, as spiders increased the lower region of the web if it intercepted the most prey over a period of 6 days. Consequently, spiders may be able to use long-term web-building experience as well as short-term prey capture experience to build better traps. In contrast to previous views of spiders, experience can contribute to intraspecific as well as to individual variations in web design.
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DUNN, L. J. (1999). PRELIMINARY INVESTIGATION OF EQUINE LEARNING AND MEMORY.
Abstract: ABSTRACT
Six horses demonstrated observation and discrimination learning and memory ability. The purpose of this study was to gain further knowledge in the area of equine learning. Performance on each task was compared in a single subject design. Subjects learned to discriminate between a black and a white bucket. The criterion for learning was set at 80% correct black bucket choice. All subjects successfully performed the discrimination task by the eighth session. Observation learning was unsuccessful; no subject reached the 80% correct criterion. Five horses were tested for memory retention of the discrimination task three weeks after the initial learning. All subjects performed the discrimination by the second session of two. These data support existing results from similar learning and memory tasks. |
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Weckerly, F. W. (1999). Social bonding and aggression in female Roosevelt elk. Can J Zool, 77(9), 1379–1384.
Abstract: Abstract: The relationship between degree of social bonding (extent of association among individuals) and level of aggression in ruminants is unclear. I examined social bonding and aggression in three groups of female Roosevelt elk (Cervus elaphus roosevelti) over 2 years. I hypothesized that when animals are socially bonded, bouts of aggression will be won by the individual initiating the aggression, occur quickly, and involve little physical contact, and the level of aggression does not correlate with group size. The degree of social bonding was high among individuals in all groups. Dyads of known individuals were together >80% of the time. A permutation analysis indicated that groups with the observed sizes had <0.001 chance of random association, except on one occasion when the probability was 0.72 for one group. Using focal-animal sampling, aggressive interactions were won 72% of the time by the initiator, occurred quickly (<5 s), and involved little physical contact, and the level of aggression was not correlated with group size. The level of aggression was, however, significantly lower in one of the groups. This group may have had access to more abundant food resources than the other groups. Socially bonded elk conducted aggressive interactions in a fashion that did not disrupt social stability. Résumé : La relation entre le degré de liaison sociale (importance des associations entre individus) et l`agressivité n`est pas claire chez les ruminants. J`ai étudié les liaisons sociales et l`agressivité chez trois groupes de femelles du Cerf de Roosevelt (Cervus elaphus roosevelti) pendant 2 ans. J`ai posé en hypothèse que, chez les animaux liés socialement, la victoire devrait être emportée par l`individu qui entreprend l`agression, l`agression devrait être de courte durée, se faire avec peu de contacts physiques et la fréquence des agressions ne devrait pas être liée à la taille du groupe. Des paires d`individus passaient plus de 80% de leur temps ensemble. Une analyse des permutations a démontré que, chez les groupes des tailles observées, la probabilité d`une association aléatoire était de moins de 0,001, sauf en un cas où cette probabilité a été évaluée à 0,72 chez un groupe. Par échantillonnage directionnel, j`ai observé que les interactions agressives étaient gagnées par l`individu attaquant 72% du temps, étaient de courte durée (<5 s), se faisaient avec peu de contacts physiques et leur fréquence n`était pas reliée à la taille du groupe. Il y avait cependant moins d`agressivité chez l`un des groupes. Il se peut que ce groupe ait eu accès à plus de ressources alimentaires que les autres. Chez les cerfs liés par des liens sociaux, l`agressivité ne se manifeste pas de façon à déséquilibrer la stabilité sociale.
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M, E., östl,., Messmann, S., Bagu, E., Robia, C., & Palme, R. (1999). Measurement of Glucocorticoid Metabolite Concentrations in Faeces of Domestic Livestock. J. Vet. Med. A, 46(10), 621–631.
Abstract: After 14C-labelled cortisol infusion in ponies and pigs, faecal samples were collected. Extraction of 0.5 g faeces with 5 ml 80–90 % methanol yielded the highest radioactivity in the supernatant. Most of the metabolites were ether soluble. After high performance liquid chromatography (HPLC), the presence of immunoreactive metabolites was demonstrated by measuring each HPLC fraction using enzyme immunoassays for cortisol, corticosterone and 11-oxoaetiocholanolone. Only the assay for 11-oxoaetiocholanolone revealed peaks with co-eluting radioactivity. For biological validation of the test system, adrenocorticotrophic hormone (ACTH) and dexamethasone were injected intravenously successively in both species (n = 6). Cortisol concentration in blood and the 11-oxoaetiocholanolone immunoreactive substances in faeces were determined. In horse faeces, basal values of 2.3–35.2 nmol/kg were measured. After ACTH administration, an increase (more than 200 % above basal values) of these metabolites was seen about 1 day after ACTH administration. After dexamethasone injection the levels decreased, reaching minimum concentrations 2 days after administration. In pigs, an increase in these metabolites was measured in only three animals after ACTH; dexamethasone did not cause a decrease. The stability of the samples after defecation was tested by storing samples from cows, horses and pigs at room temperature. It was shown that there was a significant increase in the concentration of measured cortisol metabolites in bovine, equine and porcine faeces after storage for 1 h, 4 h and 24 h, respectively. In frozen samples this effect was diminished after thawing samples at 40°C; thawing the samples at 95°C prevented an increase in immunoreactive substances.
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Koops, M. A., & Abrahams, M. V. (1999). Assessing the Ideal Free Distribution: Do Guppies Use Aggression as Public Information about Patch Quality? Ethology, 105(9), 737–746.
Abstract: Aggression can be costly to foragers, yet some recent research suggests that foragers should use aggression as a cue to patch quality (the attractive aggression hypothesis). If aggression is predictive of patch quality, then the attractive aggression hypothesis predicts that the distribution of foragers should follow the distribution of aggression. If, instead, aggression is repulsive because it is costly, then the distribution of foragers should diverge from the distribution of aggression. We tested the attractive aggression hypothesis using female guppies, Poecilia reticulata, and found that the distribution of foragers followed the distribution of food, but was unaffected by the distribution of aggression. These data do not support the attractive aggression hypothesis, but instead suggest that the distribution of aggression is a consequence of the distribution of foragers, and that aggression is not used as public information about patch quality.
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Rogers, C. W., Davies, A. S., Pfeiffer, D. U., & Davie, P. S. (1999). Linear and temporal stride characteristics of 3-day event horses at a CCI*** 3-day event horse inspection. N Z Vet J, 47(6), 193–197.
Abstract: AIMS: To quantify the linear and temporal characteristics of the trot of 3-day event horses during the preliminary horse inspection of an advanced grade CCI* 3-day event. METHODS: A cross sectional study was made of the kinematics of 24 3-day-event horses during the first horse inspection at a CCI* level S-day event. Video footage was digitised and linear and temporal measurements were made. RESULTS: The horses trotted for an average of 10.44+/-1.55 strides. Spatial measurements were made on an average of 5.66+/-0.92 consecutive strides when the horses were within the calibration zone. The horses increased and then obtained a constant velocity within the calibration zone. Trotting on the asphalt track did not alter the relationships between stride length, stride duration and velocity when compared with previously published values. Horse-specific differences in stance and retraction percentages were identified. CONCLUSION: Horse specific differences were identified that may contribute to each horse's unique gait or kinematic fingerprint. It is proposed that the initiation of, and completion of, stance by the hind limb first may represent engagement of the hind quarters and be a response to dressage training.
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Matzke, S. M., Oubre, J. L., Caranto, G. R., Gentry, M. K., & Galbicka, G. (1999). Behavioral and immunological effects of exogenous butyrylcholinesterase in rhesus monkeys. Pharmacol Biochem Behav, 62(3), 523–530.
Abstract: Although conventional therapies prevent organophosphate (OP) lethality, laboratory animals exposed to such treatments typically display behavioral incapacitation. Pretreatment with purified exogenous human or equine serum butyrylcholinesterase (Eq-BuChE), conversely, has effectively prevented OP lethality in rats and rhesus monkeys, without producing the adverse side effects associated with conventional treatments. In monkeys, however, using a commercial preparation of Eq-BuChE has been reported to incapacitate responding. In the present study, repeated administration of commercially prepared Eq-BuChE had no systematic effect on behavior in rhesus monkeys as measured by a six-item serial probe recognition task, despite 7- to 18-fold increases in baseline BuChE levels in blood. Antibody production induced by the enzyme was slight after the first injection and more pronounced following the second injection. The lack of behavioral effects, the relatively long in vivo half-life, and the previously demonstrated efficacy of BuChE as a biological scavenger for highly toxic OPs make BuChE potentially more effective than current treatment regimens for OP toxicity.
Keywords: Animals; Antibody Formation/drug effects; Behavior, Animal/*drug effects; Butyrylcholinesterase/*immunology/pharmacokinetics/*pharmacology; Cognition/drug effects; Color Perception/drug effects; Conditioning, Operant/drug effects; Discrimination Learning/drug effects; Half-Life; Horses; Humans; Macaca mulatta; Male
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