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McComb, K., & Clutton-Brock, T. (1994). Is mate choice copying or aggregation responsible for skewed distributions of females on leks? Proc Biol Sci, 255(1342), 13–19.
Abstract: In several lek-breeding populations of birds and mammals, females arriving on leks tend to join males that already have females in their territories. This might occur either because females have an evolved preference for mating with males that are attractive to other females, or because they join groups of other females to obtain greater safety from predation or dangerous harassment by males. We have previously used controlled experiments to show that oestrous fallow deer females join males with established harems because they are attracted to female groups rather than to the males themselves. Here we demonstrate that the preference for males with females over males without females is specific to oestrous females and weak or absent in anoestrous ones, and that it is not associated with a preference for mating with males that have previously been seen to mate with other females. Furthermore, oestrous females given the choice between males that do not already have females with them show no significant preference for antlered over deantlered males or for older males over younger ones. We conclude that female attraction to other females on the lek is likely to be an adaptation to avoiding harassment in mixed-sex herds. In this situation, a male's ability to maintain the cohesion of his harem may be the principal cause of variation in mating success between males.
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Witter, M. S., & Swaddle, J. P. (1994). Fluctuating Asymmetries, Competition and Dominance. Proc. Roy. Soc. Lond. B Biol. Sci., 256(1347), 299–303.
Abstract: Levels of fluctuating asymmetry (FA) in the primary feathers of European starlings, Sturnus vulgaris, have been shown to be sensitive to nutritional and energetic stress. Furthermore, between-individual variation in plumage FA has been found to be related to social dominance, even without social interactions during feather growth, with dominant birds exhibiting the highest levels of FA. Here we examine whether the relation between dominance and FA differs when birds are housed in social groups, under different degrees of competition for food, during moult. We reason that dominants should derive a greater benefit from their social status as competition for food increases. Our results support this proposition. The relation between dominance and FA differed significantly according to the degree of competition for food. However, in no cases did the dominants exhibit lower levels of FA than subdominants. When competition for food was low, dominants had higher levels of FA than subdominants. When competition for food was high, there was no systematic relation between dominance and FA. These results suggest that dominants may only derive a net benefit from their social status, under the circumstances of our experiment, during severe conditions of competition.
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Barber, J. A., & Crowell-Davis, S. L. (1994). Maternal behavior of Belgian (Equus caballus) mares. Appl. Anim. Behav. Sci., 41(3-4), 161–189.
Abstract: The relationship between ten Belgian mares and their offspring was studied from the first day of foal life to 17 weeks of age. Mares and foals spent more time at greater distances from each other as foals matured. Mares exhibited the recumbency response, being in closer proximity to their foals when foals were recumbent than when they were upright. Foals initiated the majority of nursing bouts. Frequency and duration of nursing bouts and percentage of time resting recumbently declined as foals matured. Foals also terminated the their foals, and they were most likely to do so in the first month of foal life. Maternal initiation of nursing. There was usually no discernible foal response to maternal aggression. Little difference between maternal behavior directed towards colts and fillies was found for all aspects of the study. Maternal behavior in the Belgian draft horse was similar to that reported for other equid breeds.
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Crowell-Davis, S. L. (1994). Daytime rest behavior of the Welsh pony (Equus caballus) mare and foal. Appl. Anim. Behav. Sci., 40(3-4), 197–210.
Abstract: Upright and recumbent rest of 15 Welsh pony foals and their mothers was studied over a 2 year period. During their first week of life, the foals spent 32% of the time in recumbent rest. Subsequently, the percentage of time spent in recumbent rest decreased, but was still greater than for the foal's mother by Week 21, when the foals spent 6.5% of their time in recumbent rest. Adults spent little time in recumbent rest. Foals rested upright only 3.5% of the time during their first week of life. Mares rested upright more than foals did to Week 13, at which time peak values for time spent in upright rest occurred for both mares (32.5%) and foals (23%). Subsequently, mares and foals spent equal, but decreasing, amounts of time resting upright. The total time spent resting by the foals decreased gradually, and was characterized by a transition from recumbent rest to upright rest. Foals were more likely to be resting, either recumbent or upright, if their mother was resting upright. During the late spring, summer, and early autumn, mares and foals were most likely to be resting upright between 09:00 and 17:00 h.
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Minton, J. E. (1994). Function of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system in models of acute stress in domestic farm animals. J. Anim Sci., 72(7), 1891–1898.
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Walter, G., & Reisner, A. (1994). Student opinion formation on animal agriculture issues. J. Anim Sci., 72(6), 1654–1658.
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Gonyou, H. W. (1994). Why the study of animal behavior is associated with the animal welfare issue. J. Anim Sci., 72(8), 2171–2177.
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Sappington, B. F., & Goldman, L. (1994). Discrimination learning and concept formation in the Arabian horse. J. Anim Sci., 72(12), 3080–3087.
Abstract: Discrimination learning and concept formation abilities were investigated in four mature Arabian horses. A series of two-choice discrimination problems were presented on stimulus panels that could open to allow access to food bowls. Selection of the correct stimulus resulted in food reinforcement, and an incorrect choice was not rewarded. The positions of the correct and incorrect stimuli were varied randomly during each test session, and the criterion for learning each problem was 85% correct for two consecutive sessions of 30 or 40 trials. Testing progressed through six discrimination problems. The first four were simple pattern discriminations, but the last two incorporated several different triangles as correct stimuli and thus involved the concept of triangularity. Two of the subjects successfully completed only simple pattern discriminations, one showed evidence of learning in the first concept problem, and one completed all six tests, including the two concept formation problems. The results demonstrate complex pattern discrimination ability in horses, and suggest that they may also have the ability to form and use concepts in problem solving.
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Marinier, S. L., & Alexander, A. J. (1994). The use of a maze in testing learning and memory in horses. Appl. Anim. Behav. Sci., 39(2), 177–182.
Abstract: Two mazes were used to test the learning ability and memory of horses, and changes in these abilities. Testing was done on four occasions. On Occasion 1, the horses were run through Maze A until they had reached the criterion of three consecutive correct runs. A week later (Occasion 2), they were retested in Maze A to the same criterion as a measure of memory. On Occasion 3,2 months later, the horses were run through Mazes A and B until they reached the criterion. Occasion 4 took place 1 week later when they were run through Mazes A and B. An estimation of changes in ability to learn came from a comparison of results from Occasions 1 and 3. Similarly, changes in ability to remember came from a comparison of results from Occasions 2 and 4. Nine horses with a variable amount of riding training were the subjects. All horses were able to learn the maze, but the ability varied among horses. There was no obvious correlation between quality of handling of the horses and learning ability. Once the horses had learned the maze, they remembered it perfectly on subsequent occasions. There were changes in the memory and learning ability of the horses, but no clear explanation for this could be found.
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Mal, M. E., McCall, C. A., Cummins, K. A., & Newland, M. C. (1994). Influence of preweaning handling methods on post-weaning learning ability and manageability of foals. Appl. Anim. Behav. Sci., 40(3-4), 187–195.
Abstract: Twenty-three foals were used to determine if different amounts of handling between birth and weaning affected their later learning ability and manageability. Foals were assigned to one of three treatments: non-handled (NH) foals were not handled except for necessary maintenance procedures; intermediately handled (IH) foals were handled daily in two 10-min sessions for 7 days after birth and then not handled except for necessary maintenance procedures; extensively handled (EH) foals were handled daily for 7 days as were IH foals and then handled for 10 min once weekly until weaning. Foals were weaned at 120 +/- 10 days of age. On days 1, 3, and 15 after weaning, foals were subjected to a one-trial learning test. The learning test consisted of placing the foal in a familiar pen with an 1.5 X .6-m apparatus containing 40 15 X 15-cm compartments. Number of visits to the apparatus and compartment visited were recorded for 5 min. A small amount of concentrate feed then was placed in a target compartment, and visits were recorded for an additional 5 min. On day 16 after weaning, foals were subjected to a manageability test in which flight distance from an unfamiliar handler and reaction to a novel stimulus were recorded. Split-plot analysis of variance revealed no treatment differences in performance on the learning test (P > .05). Foal performance on the test was greater on day 15 than on day 1 or day 3 (P < .01). Analysis of variance indicated handling treatment had no effect (P > .05) on foal performance during the manageability test. Results indicate that this preweaning handling regimen has no effect on foal learning ability or manageability as measured by these procedures.
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