Sprigge, T. L. S. (2000). Darwinian Dominion: Animal Welfare and Human Interests: Lewis Petrinovich, Cambridge, Mass, London, England, MIT Press, 1999, ix + 431 pages, {pound}31.50 (hc). J. Med. Ethics, 26(5), 412–.
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Lanier, J. L., Grandin, T., Green, R. D., Avery, D., & McGee, K. (2000). The relationship between reaction to sudden, intermittent movements and sounds and temperament. J. Anim Sci., 78(6), 1467–1474.
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Olesen, I., Groen, A. F., & Gjerde, B. (2000). Definition of animal breeding goals for sustainable production systems. J. Anim Sci., 78(3), 570–582.
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Marc, M., Parvizi, N., Ellendorff, F., Kallweit, E., & Elsaesser, F. (2000). Plasma cortisol and ACTH concentrations in the warmblood horse in response to a standardized treadmill exercise test as physiological markers for evaluation of training status. J. Anim Sci., 78(7), 1936–1946.
Abstract: Reliable physiological markers for performance evaluation in sport horses are missing. To determine the diagnostic value of plasma ACTH and cortisol measurements in the warmblood horse, 10 initially 3-yr-old geldings of the Hannovarian breed were either exposed to a training schedule or served as controls. During experimental Phase 1, horses were group-housed, and half of the horses were trained for 20 wk on a high-speed treadmill. During Phase 2, groups were switched and one group was trained for 10 wk as during Phase 1, whereas the control group was confined to boxes. During Phase 3 horses were initially schooled for riding. Thereafter, all horses were regularly schooled for dressage and jumping, and half of the horses received an additional endurance training for 24 wk. During all phases horses were exposed at regular intervals to various standardized treadmill exercise tests. During and after the tests frequent blood samples were taken from an indwelling jugular catheter for determination of ACTH and cortisol. Treadmill exercise increased both hormones. Maximum ACTH concentrations were recorded at the end of exercise, and maximum cortisol levels were recorded 20 to 30 min later. Except for one test there were no differences in ACTH levels between trained horses and controls. There was no significant effect of training on the cortisol response (net increase) to treadmill exercise in any of the tests during Phase 1. During Phase 2 higher cortisol responses were recorded in controls than in trained horses (P < .05) after 10 wk of training (controls confined to boxes). During Phase 3 plasma cortisol responses were also higher in controls than in trained horses (P < .05 after 6, 18, and 24, P < or = .07 after 12 wk of training) when the inclination of the treadmill was 5%, but not at 3%. There was no overlap in net cortisol responses at 30 min between trained and untrained horses. An ACTH application after 24 wk of training resulted in higher cortisol responses in controls than in trained horses (P < or = .05), without any overlap between the groups at 30 min after ACTH. Plasma cortisol responses to either treadmill exercise or ACTH injection may be a reliable physiological marker for performance evaluation. Prerequisites are sufficient differences in training status and sufficient intensity of exercise test conditions.
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McCutcheon, L. J., & Geor, R. J. (2000). Influence of training on sweating responses during submaximal exercise in horses. J Appl Physiol, 89(6), 2463–2471.
Abstract: Sweating responses were examined in five horses during a standardized exercise test (SET) in hot conditions (32-34 degrees C, 45-55% relative humidity) during 8 wk of exercise training (5 days/wk) in moderate conditions (19-21 degrees C, 45-55% relative humidity). SETs consisting of 7 km at 50% maximal O(2) consumption, determined 1 wk before training day (TD) 0, were completed on a treadmill set at a 6 degrees incline on TD0, 14, 28, 42, and 56. Mean maximal O(2) consumption, measured 2 days before each SET, increased 19% [TD0 to 42: 135 +/- 5 (SE) to 161 +/- 4 ml. kg(-1). min(-1)]. Peak sweating rate (SR) during exercise increased on TD14, 28, 42, and 56 compared with TD0, whereas SRs and sweat losses in recovery decreased by TD28. By TD56, end-exercise rectal and pulmonary artery temperature decreased by 0.9 +/- 0.1 and 1.2 +/- 0.1 degrees C, respectively, and mean change in body mass during the SET decreased by 23% (TD0: 10.1 +/- 0.9; TD56: 7.7 +/- 0.3 kg). Sweat Na(+) concentration during exercise decreased, whereas sweat K(+) concentration increased, and values for Cl(-) concentration in sweat were unchanged. Moderate-intensity training in cool conditions resulted in a 1.6-fold increase in sweating sensitivity evident by 4 wk and a 0.7 +/- 0.1 degrees C decrease in sweating threshold after 8 wk during exercise in hot, dry conditions. Altered sweating responses contributed to improved heat dissipation during exercise and a lower end-exercise core temperature. Despite higher SRs for a given core temperature during exercise, decreases in recovery SRs result in an overall reduction in sweat fluid losses but no change in total sweat ion losses after training.
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Parr, L. A., Winslow, J. T., Hopkins, W. D., & de Waal, F. B. (2000). Recognizing facial cues: individual discrimination by chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta). J Comp Psychol, 114(1), 47–60.
Abstract: Faces are one of the most salient classes of stimuli involved in social communication. Three experiments compared face-recognition abilities in chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta). In the face-matching task, the chimpanzees matched identical photographs of conspecifics' faces on Trial 1, and the rhesus monkeys did the same after 4 generalization trials. In the individual-recognition task, the chimpanzees matched 2 different photographs of the same individual after 2 trials, and the rhesus monkeys generalized in fewer than 6 trials. The feature-masking task showed that the eyes were the most important cue for individual recognition. Thus, chimpanzees and rhesus monkeys are able to use facial cues to discriminate unfamiliar conspecifics. Although the rhesus monkeys required many trials to learn the tasks, this is not evidence that faces are not as important social stimuli for them as for the chimpanzees.
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Rendall, D., Cheney, D. L., & Seyfarth, R. M. (2000). Proximate factors mediating “contact” calls in adult female baboons (Papio cynocephalus ursinus) and their infants. J Comp Psychol, 114(1), 36–46.
Abstract: “Contact” calls are widespread in social mammals and birds, but the proximate factors that motivate call production and mediate their contact function remain poorly specified. Field study of chacma baboons (Papio cynocephalus ursinus) revealed that contact barks in adult females were motivated by separation both from the group at large and from their dependent infants. A variety of social and ecological factors affect the probability of separation from either one or both. Results of simultaneous observations and a playback experiment indicate that the contact function of calling between mothers and infants was mediated by occasional maternal retrieval rather than coordinated call exchange. Mothers recognized the contact barks of their own infants and often were strongly motivated to locate them. However, mothers did not produce contact barks in reply unless they themselves were at risk of becoming separated from the group.
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Guth S., & Guth W. (2000). Morality based on cognition in primates. Journal of Consciousness Studies, 7, 43–46.
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Houpt, K., Marrow, M., & Seeliger, M. (2000). A preliminary study of the effect of music on equine behavior. Journal of Equine Veterinary Science, 20(11), 691–737.
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Merl, S., Scherzer, S., Palme, R., & Möstl, E. (2000). Pain causes increased concentrations of glucocorticoid metabolites in horse feces. J Equine Vet Sci, 20(9), 586–590.
Abstract: The concentration of 11,17-dioxoandrostanes (11,17-DOA), a group of cortisol metabolites, was measured using enzyme immunoassay in fecal samples of horses experiencing painful episodes. One group of horses consisted of 10 stallions castrated (samples were collected daily for 10 days); the other group was made up of 29 horses which were brought to an animal hospital because of signs of colic (samples were collected twice daily for six days). Before castration, median concentrations of 10.5 nmol/kg feces were measured. On days 1 and 2 after castration, median 11,17-DOA values increased up to 26.2 and 50.0 nmol/kg feces, respectively, and decreased thereafter to levels lower than at the beginning of the sampling period. High variations were measured between individual cases of colic. In animals with colic, all horses excreted more than 33 nmol 11,17-DOA/kg feces for various periods. The highest concentration measured was 885 nmol/kg feces. One animal out of the 29 colic horses did not show any clinical signs of pain upon arrival in the hospital. The 11,17-DOA values were below 17 nmol/kg feces in all those samples. From this data we conclude, that the concentration of 11,17-DOA in feces is a parameter for painful situations that have occurred one or two days earlier.
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