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Chandler M, Fritz AS, & Hala S. (1989). Small scale deceit: deception marker of 2-, 3- and 4-year-olds' early theories of mind. Child Dev., 60, 1263.
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de Waal, F. B. (1989). Dominance “style” and primate social organization. In V. Standen, & R. A. Foley (Eds.), Comparative Socioecology (pp. 243–263). Blackwell Science.
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Trim, C. M., Moore, J. N., & Clark, E. S. (1989). Renal effects of dopamine infusion in conscious horses. Equine Vet J Suppl, (7), 124–128.
Abstract: An ultrasonic flow probe was implanted around a branch of the left renal artery in five horses. The effects of dopamine were studied in the unsedated horses 10 days after surgery. Three experiments, separated by at least two days, were performed in random order on each horse. In two experiments, dopamine was infused intravenously for 60 mins at either 2.5 and 5.0 micrograms/kg bodyweight (bwt)/min. Saline was infused for 60 mins before and after each infusion, and for 180 mins in the third experiment as a control. Renal blood flow increased during administration of dopamine at both dose rates (P = 0.0001). Urine volume increased (P = 0.055), and osmolality decreased (P < 0.05), with infusion of dopamine at 5.0 micrograms/kg bwt/min. Arterial blood pressure and heart rate were not significantly affected. Fractional excretions of sodium and potassium were not significantly changed with dopamine infusion. The higher dopamine dose rate was accompanied by dysrhythmias in some horses.
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Klingel, H. (1989). Odd-toed Ungulates, Horses. In B. Grzimek (Ed.), Grzimek's Encyclopedia of Mammals (Vol. 4, 550+pp. 557–594). McGraw Hill.
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Povinelli DJ. (1989). Failure to find self-recognition in Asian elephants (Elephas maximus) in contrast to their use of mirror cues to discover hidden food. J. Comp. Psychol., 103, 122.
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Herder, S. L. (1989). More cardiac dressage: galop, gallop, gal(l)opitty glop. Jama, 262(3), 352.
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Hunter, L., & Houpt, K. A. (1989). Bedding material preferences of ponies. J Anim Sci, 67(8), 1986–1991.
Abstract: The bedding preferences of ponies were determined using video recordings of nighttime (1900 to 0700) behavior of individually housed ponies. The ponies' behavior each minute was recorded to determine time budgets. In Exp. I, preference for bedding was determined using three mares, three stallions and two geldings given access to bedded and unbedded areas in a box stall. The ponies spent more time (66%) on the bedded area and were never observed lying on the unbedded areas. In Exp. II, three mares and six stallions were given access to a box stall, one side of which was bedded with wood shavings and the other with straw. Although some individual animals preferred one bedding over the other, neither form of bedding was preferred consistently. Time budgets in Exp. II were similar on both bedding materials. The ponies spent 12% of their nighttime lying, 2% walking, 35% eating and 50% standing inactively. Some ponies had a relatively strong preference for bedding, but the type of bedding preferred varied with the individual animal. Some individual ponies had no clear preference, but instead had a side or position preference
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Rubenstein, D. I. (1989). Life history and social organization in arid adapted ungulates. J. Arid. Environ., 17, 145–156.
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Fragaszy, D. M., & Visalberghi E. (1989). Social influences on the acquisition of tool-using behaviors in tufted capuchin monkeys (Cebus apella). J. Comp. Psychol., 103(2), 159–170.
Abstract: To identify behaviors related to acquisition of tool-use in tufted capuchins (Cebus apella), we presented two tool-using tasks to two groups, extending findings by Westergaard and Fragaszy (1987) and Visalberghi (in press). Five Ss learned to use the tools in each task. The primary predictor of success was level of interest in the task. Observation of others at the apparatus did not facilitate exploratory behaviors or contact with the tools in the observers. Most animals performed exploratory behaviors more often when they were at the apparatus alone than when with another, whether or not the other was using a tool. Observers were quick to learn the relationship between another's activities and the appearance of food. We conclude that capuchins do not readily learn about instrumental relations by observation of others or imitate other's acts. Imitation probably plays no role in the spread of novel instrumental behaviors among monkeys. (PsycINFO Database Record (c) 2010 APA, all rights reserved)
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Huizinga, H. A., & van der Meij, G. J. W. (1989). Estimated parameters of performance in jumping and dressage competition of the Dutch Warmblood horse. Livestock Production Science, 21(4), 333–345.
Abstract: The objective of this study is to estimate several genetic parameters in the Dutch Warmblood riding horse population. The traits involved are performances in jumping and dressage competition. The following parameters are estimated: heritabilities for jumping and dressage; phenotypic and genetic correlations between jumping and dressage; and phenotypic and genetic correlations between performances at different ages. These parameters are estimated by restricted maximum likelihood (REML). Data are from 6899 horses with performances in jumping and 10 408 horses with performances in dressage competition. The horses are sired by 205 and 237 stallions for the two traits, respectively. The progeny range in age from 4 to 8 years old. The performance trait is a cumulatively derived score, that reflects the level of performance in competition. A square root transformation of the score is most appropriate to normalize the data. For estimation of phenotypic and genetic parameters the data is split into two data sets according to the age of the sires (offspring sired by older vs. younger stallions). For estimating correlations between performances at 4, 5 and 6 years of age, performances of the offspring out of previous years are linked to the data. The most unbiased estimates of heritability for jumping and dressage are from data derived from the youngest offspring sired by the younger stallions and are 0.20 and 0.10, respectively. Genetic correlation between jumping and dressage ranges from -0.27 to 0.10. The phenotypic correlation between these traits ranges from 0.15 to 0.26. Phenotypic and genetic correlations between performances at 4, 5 and 6 years average 0.95 and 0.75, respectively. These latter results have important implications for genetic evaluation of breeding candidates in the population.
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