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.

Abstract: Data were collected on 972 aggressions and 233 acts of mutual grooming in a herd of 9 Przewalski horses in the Hellabrunn Tierpark in Munich, West Germany. The herd was composed of 1 adult stallion, 5 adult mares and 3 foals. A distinct linear dominance hierarchy was present in the herd, with the stallion being the top-ranking animal. Age was significantly correlated with rank. Almost 40% of all aggressions consisted of herding actions by the stallion. Threats to bite (20% of all aggressions) and threats to kick (11.4%) were next in frequency of occurrence. Most mutual grooms (71%) involved grooming the front part of the body. Although mutual grooming may be used to appease higher-ranked animals, most grooming bouts were between related horses. Foals initiate 47.6% of all allogrooming. Mutual grooming may reduce weaning conflict between a mare and her foal or may result in female coalitions that defend against predators or aggression by the herd stallion.

Abstract: The Minnesota Zoological Garden established a bachelor (i.e. all-male) group of 8 Przewalski horses (Equus przewalskii) in 1984. Possible methods for mixing males emerged through preliminary introductions and review of the relevant literature. These included: (1) grouping colts (<=3 years old) after removing them from their natal bands; (2) introducing adult stallions to colts in spacious, controlled environments to reduce the risk of combat-related injury or death associated with largely unpredictable adult temperament; (3) introducing more than 1 animal at a time to established groups. Based on the frequency and orientation of agonistic interactions observed among the bachelors, a linear dominance hierarchy was discerned among the 4 adult stallions; all 4 colts were determined to be of equally low or seemingly non-ranking status. Social rank among the adults was most influenced by individual temperament, and contention for rank was limited almost exclusively to the 3 lower-ranking stallions; the alpha male participated in 73% of all agonistic interactions observed, but was identified as the recipient in less than 3% of these interactions. Intra-band associations were detected in the bachelor group. The most prevalent of these was among the 4 colts, found together in over 70% of the observations. Other affinities commonly observed were between the colts (as a sub-group) and different stallions. The dominant stallion, the colts' most frequent companion, actively discouraged the 3 lower-ranking stallions from associating with the colts. Further, the colts were subjected to significantly fewer agonistic behaviors than the non-alpha stallions (per colt=1.05+/-0.24 h-1; per non-alpha stallion=2.01+/-0.04 h-1). These findings support the hypothesis developed by other workers for ungulates that young bachelors are sheltered from aggression by association with an alpha male. With one exception, adult associations were rarely noted. Although combat-related injuries (superficial wounds and temporary lameness) were common among the bachelors, few required medical attention. No permanent disabilities or deaths have occurred since the group's inception. The existence of social organization and intra-band associations in the bachelor group support the suggestion that such groups were once a natural part of this species' social milieu. Bachelor groups are therefore recommended as an ethologically sound, space- and cost-effective means of managing “surplus” (i.e. non-harem) male Przewalski horses.

Abstract: The ethological structure of the herd of Przewalski horses includes hierarchic ranks of horses which determine their social roles in the herd. Besides the age ranks, the wild horses are characterized by the formation of harem groups, a “leading” group of females, a group of bachelor stallions, family groups, etc. The ethological structure determines the spatial one, which is the form of distribution of horses over the territory, and its assimilation and transformation into a system of informative spatial units. Under the influence of “internal” and “external” stimuli, the intragoup regulatory mechanims (social adaptations) manifest themselves, which allow the herd to function in the complicated situation of the reserve and allow humans to control the herd by using these mechanisms. There are grounds to believe that, given the balanced ethological structure of these groups, wild horses could be successfully acclimatized into natural biotopes.

Abstract: Following the introduction of a new stallion to a band of E. przewalskii mares two births, both of male foals, resulted in foal death due to injuries sustained in the first day of life. Neither foal was sired by the new herd stallion. The second foal death was the results of an observed attack on the newborn male and is described here. Subsequently births in the same enclosure and, in one instance, to the same mare whose previous foal was killed, were of foals sired by the new stallion and were uneventful, with 3 male foals surviving to date.