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Houpt, K. A., Perry, P. J., Hintz, H. F., & Houpt, T. R. (1988). Effect of meal frequency on fluid balance and behavior of ponies. Physiol. Behav., 42(5), 401–407.
Abstract: Twelve ponies were fed their total daily ration either as one large meal or divided into six small meals. Pre- and post-feeding behavior was recorded six times a day. Blood samples were taken for 30 min before and two hr after the meal. Plasma protein increased from 7.0 to a peak of 7.3 g/dl with small meals and from 7.3 to 8.1 g/dl with large meals, and returned to pre-feeding levels by 90 min post-feeding. Hematocrit rose from 33.3 to 34.1% with small meals and from 33.0 to 36.0% with large meals. These rapid and short-lived increases indicate a decrease in plasma volume. Plasma osmolality rose with feeding from 283 to 285 mosmoles/kg with small meals and from 281 to 288 mosmoles/kg with large meals. Water availability had no significant effect on blood changes. Digestibility and rate of passage were measured with chromic oxide, but there were no differences. Vocalizing (neighing) and walking occurred more often before than after feeding, while eating bedding and engaging in other oral behaviors were more frequent after feeding.
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Carroll, C. L., & Huntington, P. J. (1988). Body condition scoring and weight estimation of horses. Equine Vet J, 20(1), 41–45.
Abstract: Three hundred and seventy two horses of varying breeds, height and fatness were weighed and measured for height at the withers. They were assessed for condition score by adaptation of a previously published method. The heart girth and length of 281 of the horses were also measured. Weight of horses was highly correlated (P less than 0.001) with height (r2 = 0.62), condition score (r2 = 0.22) and girth2 x length (r2 = 0.90). Nomograms were constructed to predict weight from height and condition score, and girth and length measurements. Weight can also be accurately estimated from the formula: (formula, see text) The average value of 'Y' in this experiment was 11900 and this estimated weight with more accuracy than some previously published values of 'Y'. Racing Thoroughbred horses were found to be significantly lighter than non-racing Thoroughbreds of the same height and condition score. The method of assessment of condition score was shown to be repeatable between different operators with varying degrees of experience.
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Steinhoff, H. J. (1988). A continuous wave laser T-jump apparatus and its application to chemical reactions in hemoglobin single crystals. J Biochem Biophys Methods, 15(6), 319–330.
Abstract: A laser temperature jump apparatus is constructed where the T-jump is achieved by means of the direct absorption of continuous laser radiation of low intensity by a solid sample. The final temperature in the irradiated volume element is reached when the absorbed radiation power equals the dissipation of heat by heat conduction. The time range from the beginning of irradiation to the stationary state depends on the geometry of the irradiated volume element and is less than 10 ms. The heating laser beam is simultaneously used to detect the relaxation to the new chemical equilibrium in the sample. Relaxation processes with relaxation rates between 10(2) s-1 and less than 10(-3) s-1 on samples with volumes less than 10(-3) mm3 may be investigated using this T-jump method. One application of this method is the determination of reaction rates of ligand reactions in hemoglobin single crystals. Rate constants obtained for the reaction of thiocyanate with crystallized horse methemoglobin are presented.
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Kozarovitskii, L. B. (1988). [Further comment on the distinction between humans and animals]. Nauchnye Doki Vyss Shkoly Biol Nauki, (3), 42–45.
Abstract: The problem of mind is considered in the aspect of natural scientific and philosophical problem of distinction between human and animal. The widespread confusion of the terms “rudiments”, “elements” of specifically human properties in animals and “biological prerequisites” of these properties are critically analysed. The idea is formulated according to which only in the process of anthropogenesis the rudiments of new social property--mind, conscience--could appear in the developing human beings.
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Levin, L. E., & Grillet, M. E. (1988). [Diversified leadership: a social solution of problems in schools of fish]. Acta Cient Venez, 39(2), 175–180.
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Thackeray, J. F. (1988). Zebras from wonderwerk cave, northern Cape province, South Africa: attempts to distinguish Equus burchelli and E. quagga. Suid- Afrikaanse Tydsskrif vir Wetenskap, 84, 99–101.
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Ryder, O. A. (1988). Przewalski's horse – putting the wild horse back in the wild. Oryx, 22, 154–157.
Abstract: The Asian wild horse, or Przewalski's horse (Equus przewalskii), is believed to currently survive only in captivity. There are more than 660 individuals in over 70 zoological collections, and animals are available for reintroduction. The Przewalski's horse had been bred in captivity for 12 generations, and inbreeding has occurred. Genetic variability has been lost, and released animals will require acclimatization on or near release sites. In China, a program is under way for acclimatization, breeding, and release of wild horses, and plans are being made for a similar program in Mongolia. (LCA)
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Brennan, J., & Anderson, J. (1988). Varying responses to feeding competition in a group of rhesus monkeys (Macaca mulatta). Primates, 29(3), 353–360.
Abstract: The behaviour of members of a group of rhesus monkeys was observed in experimentally created, competitive feeding situations. Socially dominant members of the group tended to start eating before lower-ranking subjects, and generally ate more. Dominants sometimes used aggression to control access to food, but overall, intermediate-ranking monkeys were involved in most agonistic episodes. Non-dominant subjects improved their feeding performance when food was presented in three piles rather than one pile, often by snatching food and consuming it away from the pile. These general patterns were less evident when realistic snake models were placed on some of the food piles. Feeding was disrupted by the presence of snakes, but notably, subordinates risked feeding in these conditions. Piles containing preferred foods and snakes were eaten from, but a low-preference food (carrot) under snakes went untouched by all subjects. The results suggest that group-members evaluate potential risks and benefits of competing for a restricted resource, and that dominance status, while an important factor, is only one element in the equation.
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Rogers, A. R. (1988). Does Biology Constrain Culture? Am Anthropol, 90(4), 819–831.
Abstract: Most social scientists would agree that the capacity for human culture was probably fashioned by natural selection, but they disagree about the implications of this supposition. Some believe that natural selection imposes important constraints on the ways in which culture can vary, while others believe that any such constraints must be negligible. This article employs a “thought experiment” to demonstrate that neither of these positions can be justified by appeal to general properties of culture or of evolution. Natural selection can produce mechanisms of cultural transmission that are neither adaptive nor consistent with the predictions of acultural evolutionary models (those ignoring cultural evolution). On the other hand, natural selection can also produce mechanisms of cultural transmission that are highly consistent with acultural models. Thus, neither side of the sociobiology debate is justified in dismissing the arguments of the other. Natural selection may impose significant constraints on some human behaviors, but negligible constraints on others. Models of simultaneous genetic/cultural evolution will be useful in identifying domains in which acultural evolutionary models are, and are not, likely to be useful.
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Penzhorn, B. L., & van der Merwe, N. J. (1988). Testis size and onset of spermatogenesis in Cape mountain zebras (Equus zebra zebra). J Reprod Fert, 83, 371–375.
Abstract: Testis mass of adult Cape mountain zebra stallions (mean 70·0 g) was appreciably less than that of other zebra species and domestic horses. The histological appearance of the testes of 11-, 24- and 29-month-old colts was typically prepubertal. Spermatogenic activity of a 4-year-old stallion obtained at the end of summer was at a very low level, while a 4·5-year-old stallion obtained 6 weeks after the winter solstice showed a marked increase in spermatogenesis compared with the 4-year-old. Stallions 6·5-19 years of age collected in different seasons all showed active spermatogenesis.
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