van Dierendonck, M. C., Bandi, N., Batdorj, D., Dugerlham, S., & Munkhtsog, B. (1996). Behavioural observations of reintroduced Takhi or Przewalski horses (Equus ferus przewalskii) in Mongolia. Appl. Anim. Behav. Sci., 50(2), 95–114.
Abstract: During 1992 and 1993, 14 reintroduced Przewalski Horses or Takhi (Equus ferus przewalskii) were studied in the Hustain Nuruu Mountain Steppe reserve in Mongolia. Most of the individuals did not know each other before reintroduction. These Takhi were the first of five groups due to be released in the reserve after an acclimatisation period of at least 1 year. During acclimatisation the Takhi, lived visually and acoustically separately, in fenced enclosures of approximately 45 ha each. The observations, mostly scan-sampling, were carried out in each season. The observation bouts were divided over six periods and over two harem herds. Two of the periods were in the same consecutive seasons, so comparison over the years was possible. Social integration within the Takhi herds was very high from the beginning, as described by the spatial relation and synchronisation data. Between 50 and 89% of the observation time, the behaviour of all herd members was synchronised. The amount of time spent grazing by the Takhi (30-68% of the daylight period) was similar to that of feral horses and Takhi in captivity and semi-reserves. The Takhi tended to rest in the morning and have a bimodal period of grazing at dawn and in the afternoon. The Takhi displayed clear habitat preferences for certain activities. They had a strong preference to rest at the highest point in their enclosure. They fed preferably on two or three different vegetation types (with five types available in each enclosure). The amount of time spent grazing during the non-growing seasons (49 +/- 15%) indicates that the feeding value and availability of food were sufficient. Health changes were detected adequately using condition scoring sheets. No supplementary food or water was supplied during the harsh winters. Moreover, low mortality rates and high reproductive success show that the mountain steppe is a habitat which is potentially suitable for establishing a healthy Takhi population. Takhi is the first species to return to its native habitat after living only in zoos for so many generations.
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Wolff, A., & Hausberger, M. (1996). Learning and memorisation of two different tasks in horses: the effects of age, sex and sire. Appl. Anim. Behav. Sci., 46(3-4), 137–143.
Abstract: Learning and memory abilities of 1-3 year old horses were assessed using instrumental and spatial tasks. No important differences were observed in the success of learning of the instrumental task (chest opening) according to sex or age. Younger females, however, seemed to learn more quickly. The offspring of a particular stallion were slower to learn than other horses. All horses memorised this task and opened the chest in a very short time in the second session. The animals that learned the task easily were not necessarily faster in the memorisation test. In the spatial task, learning ability did not seem to be related to age but more females than males were successful. The offspring of one stallion were more successful than other horses. Only 76% of the horses succeeded in the memorisation test, independently of age or sex. No correlation was found between the tasks in the latencies of either the learning or the memorisation tests for the same horses. The instrumental and spatial tasks may involve different processes.
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Packer, C., & Heinsohn, R. (1996). Response:Lioness leadership. Science, 271(5253), 1215–1216.
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Gary C. Jahn, & Craig Packer, R. H. (1996). Lioness leadership. Science, 271(5253), 1216–1219.
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Kaseda, Y., & K. Nozawa, K. (1996). Father-daughter matings and its avoidance in Misaki feral horses. Anim Sci Tech, 67(11), 996–1002.
Abstract: Father-daughter matings and its avoidance mechanism were analysed on the basis of data which gained from behavioural observations and paternity tests in Misaki feral horses from 1979 to 1994. Twelve stallions and their 51 daughters had 176 breeding seasons, but they lived in the different home range in 82 breeding seasons. About half of 1- to 3-year-old mares emigrated from natal area to the other and grew up there. Therefore, emigrations of young mares may result reduction of contacts and avoidance of inbreeding with their fathers. The stallions and their daughters lived in the same area in 94 breeding seasons, but there were no cases that daughters which left their natal harem groups before sexual maturity formed again stable consort relations with their natal harem stallions. It is possible that separation of young mares from their natal groups before sexual maturity may result avoidance of formation of consort relation with their fathers. Two father-daughter matings were observed in 124 paternity tests. These two daughters were born in the other harem groups than their father's and left their natal groups before maturity. After maturity, one of them formed a stable consort relation with her father and the other remained together with her father for 2 months in the breeding season. Both of them had not experience to have lived with their fathers before maturity. The persent result supports the hypothesis in wild and semi-wild horses that inbreedings between fathers and daughters may be avioded by the experience to have lived together before sexual maturity.
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Kaseda, Y., & Khalil, A. M. (1996). Harem size and reproductive success of stallions in Misaki feral horses. Appl. Anim. Behav. Sci., 47(3-4), 163–173.
Abstract: Over a 16-year period (1979-1994), long-term investigations were carried out on 14 Misaki feral stallions to analyze changes in harem size and the reproductive success. Harem size changed with the age of the stallions. Most stallions formed harem groups with four to five mares at the age of 4-6 and then the number of mares increased rapidly to the maximum at the age of 6-9 years. Thereafter, harem size decreased gradually to a minimum with advancing age. The harem size of 60 stable harem groups ranged from 1 to 9, and the average varied from a minimum mean of 1.8 in 1988 to a maximum mean of 5.3 in 1982. Mean harem size increased as adult sex ratio increased and a significant and positive correlation was found between them. One hundred and ninety-eight sire-foal pairs were determined by a paternity test with blood types and consort relations between stallions and mares during the study period. Out of 99 foals which were born in the stable harem groups, the true sires of 84 foals (85%) were the harem stallions in which the foals were born but the remaining 15 foals (15%) were sired by other harem stallions. Two out of three stallions which were studied throughout their lifetime produced 24 and 25 foals in 10 and 11 years of their reproductive lifespan, respectively. Another one produced only five foals in 6 years. The number of foals sired by the harem stallions was less than two over harem size 7 and some of the foals born in the harem were sired by other harem stallions. These results suggest that if a particular stallion monopolizes too many mares, he could not sire so many offspring because he could not always prevent his rival stallions from mating with his mares in wild or feral circumstances.
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Chenoweth, P. J., Chase, C. C., Larsen, R. E., Thatcher, M. - J. D., Bivens, J. F., & Wilcox, C. J. (1996). The assessment of sexual performance in young Bos taurus and Bos indicus beef bulls. Appl. Anim. Behav. Sci., 48(3-4), 225–235.
Abstract: Yearling beef bulls, representing different Bos indicus and Bos taurus breeds, were given two sexual performance assessments (libido score, number of services, time to first mount and time of sexual inactivity) at four test periods (January, April, July and October) in 1991 (Trial 1) and 1992 (Trial 2) at the Subtropical Agricultural Research Station, Brooksville, Florida. Breed and test period, as well as their interactions, influenced most results. Sexual performance assessments generally improved with age in Bos taurus breeds, but not in Bos indicus. The temperate Bos taurus breeds (Angus and Hereford) were most sexually active, the tropically adapted Bos taurus breeds (Senepol and Romosinuano) intermediate and the two Bos indicus breeds (Brahman and Nellore x Brahman) were least active. Service rates were generally low. Seasonal patterns in sexual performance were not apparent, with breed and year differences occurring. Although breeds showed consistent test results, the failure of Bos indicus bulls to service in any test, indicates either sexual immaturity, or inadequate procedures for assessment of sexual performance in this breed group.
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Provenza, F. D. (1996). Acquired aversions as the basis for varied diets of ruminants foraging on rangelands. J. Anim Sci., 74(8), 2010–2020.
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Mal, M. E., & McCall, C. A. (1996). The influence of handling during different ages on a halter training test in foals. Appl. Anim. Behav. Sci., 5(2), 115–120.
Abstract: Ten foals were used to determine effects of handling during different ages on their ability to perform a halter training test. Early-handled (EH) foals (n = 5) were handled in 10 min sessions 5 d weekly from 24 h after birth until 42 d of age, then were not handled from 43 to 84 d of age. Later-handled (LH) foals (n = 5) were not handled from birth to 42 d of age, then were handled in 10-min sessions 5 d weekly from 43 to 84 d of age. At 85 d of age, each foal was subjected to a 10 min halter training test for 5 consecutive d. The test consisted of an unfamiliar handler placing a halter on each foal and attempting to make the foal walk forward for 20 m. Data recorded during each d of the halter training were duration of initial struggle, number of lunges into the air, time to first forward step, time to five consecutive forward steps, and time to travel 20 m. At the end of the 5 d halter training test, the handler assigned a subjective test rating score to each foal based on ease of training. Split-plot analysis indicated that EH foals took less time (P < 0.05) to take one step forward, five consecutive steps forward, and to travel 20 m than LH foals. One-way ANOVA indicated that EH foals had a lower (more desirable) test ratings than LH foals (P < 0.01). Results indicate that handling throughout the first 42 d of life increased foal performance on this halter training task compared to handling from 43 to 84 d of age. These results may imply the existence of a critical handling period during the first 42 d of age or a phenomenon similar to learned helplessness
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Ballew, R. M., Sabelko, J., & Gruebele, M. (1996). Direct observation of fast protein folding: the initial collapse of apomyoglobin. Proc. Natl. Acad. Sci. U.S.A., 93(12), 5759–5764.
Abstract: The rapid refolding dynamics of apomyoglobin are followed by a new temperature-jump fluorescence technique on a 15-ns to 0.5-ms time scale in vitro. The apparatus measures the protein-folding history in a single sweep in standard aqueous buffers. The earliest steps during folding to a compact state are observed and are complete in under 20 micros. Experiments on mutants and consideration of steady-state CD and fluorescence spectra indicate that the observed microsecond phase monitors assembly of an A x (H x G) helix subunit. Measurements at different viscosities indicate diffusive behavior even at low viscosities, in agreement with motions of a solvent-exposed protein during the initial collapse.
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