Abstract: A herd of 8 Przewalski horses were observed on pasture in summer. Fifteen-minute focal animal samples were used to determine the time budget of the horses during the periods 00.00-04.00, 04.00-08.00, 08.00-12.00, 12.00-16.00, 16.00-20.00 and 20.00-24.00 h EDT. The behavioral states recorded were feeding (grazing and eating grain), nursing, drinking, standing, stand-resting, self-grooming, mutual grooming, locomoting, playing, and lying laterally and sternally. The average number of behavioral states occurring per hour, and the defecation, urination, aggression and vocalization rates were also determined. Overall, the horses spent 46.4 +/- 5.9% of their time feeding, 1.3 +/- 0.1% nursing, 0.5 +/- 0.1% drinking, 20.6 +/- 5.4% standing, 15.7 +/- 3.2% stand-resting, 1.7 +/- 0.2% self-grooming, 2.2 +/- 0.7% mutual grooming, 7.4 +/- 1.0% locomoting, 1.2 +/- 0.3% playing, 1.2 +/- 0.5% lying laterally and 4.1 +/- 3.0% lying sternally. The horses averaged 45.2 +/- 5.8 behavioral states per hour, and 0.2 +/- 0.0 defecations, 0.3 +/- 0.0 urinations, 1.5 +/- 0.3 aggressions and 0.7 +/- 0.1 vocalizations per hour. The horses spent the greatest amount of time foraging between 20.00 and 04.00 h, when the temperatures were lower. They spent 68.2 +/- 2.2% of their time between 20.00 and 24.00 h feeding, but only 31.2 +/- 2.1% of their time feeding between 08.00 and 12.00 h. Recumbent rest was most common between 00.00 and 04.00 h. As temperatures rose during the daylight hours, the horses spent more time drinking and standing, rather than grazing. Stand-resting was the most common form of rest during the day. The horses exhibited the greatest number of activities per hour from 08.00 to 20.00 h. While standing in close proximity to one another during these hours, the horses exhibited the highest number of aggressions per hour (1.9-2.4).

Abstract: A split-plot experiment evaluated the effect of handling and reserpine on the autonomic heart-rate response of yearling horses to various stimuli. The emotionality levels of 32 Quarter-Horse yearlings were rated by 4 experienced horsemen on a scale from 1 to 4 (1 = most nervous and erratic disposition; 4=quiet disposition). The yearlings were subsequently classified and penned based on their emotionality level; normal or nervous. Within each emotionality group, one-half the yearlings were handled daily for 14 days and the other one-half remained free in the pens. Following the handling treatment, every yearling was individually exposed to a series of stimuli, while the heart rate was monitored via a radio-telemetry system. A second treatment, reserpine, was subsequently given intramuscularly (0.005 mg/kg body weight) to one-half the yearlings of each treatment combination of emotionality and handling. The heart rate of the yearlings to the same series of stimuli previously employed was determined at 24 and 120 h and 16 days following the reserpine injection. Summarizing the results, the handled yearlings tended to exhibit lower heart rates with the handling stimulus, but the heart rate with a more novel stimulus was not affected by the previous handling treatment. Reserpine tended to suppress the heart rate of the unhandled group during the presence of a handler, but the permanency of this effect was not evident 16 days after the drug was administered. The reserpine-treated groups tended to exhibit the lowest heart-rate response to stimuli during the 120-h test-day following the administration of the drug. Heart-rate responses to the stimuli were not different between the normal and nervous yearlings.

Abstract: Individual differences in shading behaviour within a flock of sheep could be due to differences in thermoregulatory capabilities or to the influence of social factors. The possible influence of social factors on shade-use is examined in this paper. Two measures of dominance were made on 39 Merino wethers. These were based on the hierarchy determined by butting during feeding and on priority of access to limited feed. Leadership was also assessed while driving the sheep to a woolshed and as the sheep entered weighing scales. These behavioural traits were compared with leadership to shade and shade-use observed on 9 days during summer in a small pastureless enclosure containing natural shade. Maximum ambient temperature on these 9 days varied between 29.0 and 39.5[degree sign]C. All behavioural traits examined were significantly repeatable. The two dominance ranks were negatively correlated (P<0.05). The butting hierarchy was correlated with shading behaviour; those sheep that butted the larger proportion of the flock were seen to shade for longer periods of time (P=0.05). This relationship became more significant as environmental temperature increased. Significant (P<0.05) differences in the amount of time each sheep spent shading were evident throughout the flock, but in particular seven individuals shaded much less than others. Shade-use increased in hot weather and was slightly more strongly correlated with radiation load than with air temperature. The non-shading leadership ranks were related neither to each other nor to the leadership to shade. However, the sheep that moved to shade first remained there longest (P<0.05). Reduced motivation to feed did not appear to explain early movement to shade. Few overtly aggressive or other interactions between animals were seen to be associated with movements to or within shade. Nonetheless, the results indicate that social forces do exert some influence on shade-use.

Abstract: Self-grooming behaviour of 15 mare-foal pairs was studied weekly for the first 24 weeks of the foal's life. Mares self-groomed at mean rates of 1.2-2.2 times h-1 depending on the 4-week period. Foals self-groomed more often, with a peak rate of 12.3 times h-1 occurring during Week 5-8 and a subsequent decline to 6.0 times h-1 by Weeks 21-24. Self-grooming bouts of mares and foals also differed in the proportion devoted to each type of self-grooming. During a greater proportion of their total self-grooming bouts, foals scratched their head and neck with a hind limb or bit and scratched the trunk or hind limbs with the teeth. The mares spent a greater proportion of their self-grooming bouts rubbing their head or neck on an inanimate object, another pony, or their fore limb, or rolling on the ground. Particular types of individual self-grooming bouts were engaged in for different lengths of time. Foals had longer bouts of scratching the head and neck with a hind limb, scratching or biting the fore limb or hind limb with the teeth, and rubbing the head and neck on an inanimate object, while mares had longer bouts of rolling. Some of the differences in preference for particular types of self-grooming may be the result of differences in relative size of various body parts and, consequently, relative ease of a given type of self-grooming.

Abstract: The purpose of the following study was to determine if head partitions would facilitate feeding by subordinate horses in the presence of dominant pen-mates. Six pairs of mares, each with established dominant-subordinate relationships, were allowed to compete for feed in a 112-cm trough following 24 h of deprivation. Time spent feeding by each mare in each pair was recorded with a wire-mesh partition, a solid plywood partition or no partition dividing the trough. Differences in feeding times between dominant and subordinate mares were greatest in the absence of a partition and least (P<0.05) with the wire barrier in place. Differences in feeding times with the solid plywood barrier were not significantly different from either of the other treatment conditions. It was concluded that head partitions on a trough facilitate feeding by subordinate horses in the presence of dominant pen-mates and thus provide a more equitable distribution of food resources.