Reichholf J,. (1984). Funktion und evolution des Streifenmusters bei den zebras. Säugetierk Mitt, 32, 89–95.
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SCHILDER MBH et al,. (1984). A quantitative analysis of facial expressions in the plains zebra. Z. Tierpsychol., 66, 11–32.
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Vogt H,. (1984). Quagga: DNA konserviert. Naturwiss Rdsch, 37, 327–328.
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Ralston, S. L. (1984). Controls of feeding in horses. J. Anim Sci., 59(5), 1354–1361.
Abstract: Members of the genus Equus are large, nonruminant herbivores. These animals utilize the products of both enzymatic digestion in the small intestine and bacterial fermentation (volatile fatty acids) in the cecum and large colon as sources of metabolizable energy. Equine animals rely primarily upon oropharyngeal and external stimuli to control the size and duration of an isolated meal. Meal frequency, however, is regulated by stimuli generated by the presence and (or) absorption of nutrients (sugars, fatty acids, protein) in both the large and small intestine plus metabolic cues reflecting body energy stores. The control of feeding in this species reflects its evolutionary development in an environment which selected for consumption of small, frequent meals of a variety of forages.
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Kacelnik, A., & Houston, A. I. (1984). Some effects of energy costs on foraging strategies. Anim. Behav., 32(2), 609–614.
Abstract: We consider the effect of including energy costs on the optimal strategy for animals exploiting a depleting food resource. In the context of central place foraging this leads to the problem of what load size should be brought back to the central place. Two strategies are discussed: (i) maximize gross rate of energy delivery and (ii) maximize net rate of energy delivery. The optimal load size (or optimal patch time) for net maximizers is not always larger than for gross maximizers, as has been claimed. Instead, the difference in optimal load size has the same sign as the difference between metabolic rates of travelling and foraging. We point out that the influence of costs has not always been correctly incorporated in experimental tests of the theory.
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Wolff, P. R., & Powell, A. J. (1984). Urine patterns in mice: An analysis of male/female counter-marking. Anim. Behav., 32(4), 1185–1191.
Abstract: Counter-marking in mice, Mus musculus was investigated by analysing urine deposition on filter paper marked asymmetrically with urine of the opposite sex. Intact males deposited large numbers of urine spots with a marked angular bias towards previously marked quadrants. More spots were deposited on proestrous and ovariectomized donor urine patterns, their distribution being more centrifugal on oestrous urine and more centripetal in quadrants containing a large female urine spot in a central position. In contrast, castrated male mice deposited very few spots with no angular bias. Female urine patterns showed angular bias in response to intact, but not castrated male donor urine, a larger number of spots being produced by oestrous females. Thus the pattern of deposition offers scope for two-way communication of information about reproductive potential.
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Clark, T. B., Peterson, B. V., Whitcomb, R. F., Henegar, R. B., Hackett, K. J., & Tully, J. G. (1984). Spiroplasmas in the Tabanidae. Isr J Med Sci, 20(10), 1002–1005.
Abstract: Spiroplasmas were observed in seven species of the family Tabanidae (horse flies and deer flies). This is the fifth family of the order Diptera now known to harbor spiroplasmas. Noncultivable spiroplasmas were seen in the hemolymph of three species of the genus Tabanus, and cultivable forms were isolated from the guts of six species in three genera. Isolates from T. calens and T. sulcifrons were serologically similar and closely related to a spiroplasma in the lampyrid beetle, Ellychnia corrusca. These three isolates represent a new serogroup. Isolates from Hybomitra lasiophthalma were related to Group IV strains, while those from T. nigrovittatus and Chrysops sp. both represented new serogroups. At least some tabanids probably acquire spiroplasmas from contaminated flower surfaces. The possibility of vertebrate reservoirs for some tabanid spiroplasmas remains an open question.
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Barton, M. D., & Hughes, K. L. (1984). Ecology of Rhodococcus equi. Vet Microbiol, 9(1), 65–76.
Abstract: A selective broth enrichment technique was used to study the distribution of Rhodococcus equi in soil and grazing animals. Rhodococcus equi was isolated from 54% of soils examined and from the gut contents, rectal faeces and dung of all grazing herbivorous species examined. Rhodococcus equi was not isolated from the faeces or dung of penned animals which did not have access to grazing. The isolation rate from dung was much higher than from other samples and this was found to be due to the ability of R. equi to multiply more readily in dung. Delayed hypersensitivity tests were carried out on horses, sheep and cattle, but only horses reacted significantly. The physiological characteristics of R. equi and the nature of its distribution in the environment suggested that R. equi is a soil organism.
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McFarland, D. J. (1984). Roger L. Mellgren, Editor, Animal Cognition and Behavior, North-Holland, Amsterdam (1983), p. xi. Anim. Behav., 32(2), 634–635.
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Anderson JR. (1984). The development of self-recognition: a review. Dev. Psychobiol., 17, 35.
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