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.

Abstract: In contrast to horses in pastures, it is thought that free-ranging horses do not perform latrine behaviour, i.e. a behavioural pattern whereby the animals graze and defecate in separate areas. However, few studies deal with this particular subject, reporting contrasting conclusions. We hypothesize that horses free-ranging in large heterogeneous areas do not perform latrine behaviour. Thus, we believe that grazing and elimination behaviour are spatially related: where horses graze, they will also defecate. Behavioural data were collected from Konik horses, Haflinger horses, Shetland ponies and donkeys, grazing in different nature reserves (54-80 ha). Data for the different equids were analyzed separately, as well as data for mares and stallions (Konik and donkey stallions only). We investigated the proportion of the number of defecations/urinations while grazing on the total number of defecations/urinations; furthermore, we searched for the sequence of behaviours representing latrine behaviour in the strict sense. Additionally, we analyzed the correlation between grazing behaviour and eliminative behaviour on both vegetation type level and patch level. All the female equids often continued grazing while defecating. During urination, grazing ceases in the majority of instances. Cases where a mare terminated grazing in a certain vegetation type and sward height to eliminate in another vegetation type or in another sward height within the same vegetation type were rarely observed. On the vegetation type level as well as on the patch level, there was a highly significant (P<0.001) positive correlation between grazing time and number of eliminations (or eliminating time). The high values of the correlation coefficients (in case of the defecation variables r ranges between 0.553 and 0.955; in case of the urination variables r ranges between 0.370 and 0.839) illustrate that the spatial distribution of the eliminative behaviour can be explained to a high degree by the spatial distribution of the grazing behaviour. Results in the case of the stallions are preliminary, but indicate the same pattern. Horses, free-ranging in large heterogeneous areas, do not perform latrine behaviour, but defecate where they graze. Possibly, animal density is of major importance to explain this behavioural difference with horses in pastures. We suggest that also spatial vegetation heterogeneity and plant productivity of the grazed area, as well as parasite status of the grazing animals could play a role.

Abstract: Feral horses are social animals, which have to rely on survival strategies centered on the formation of cohesive social bonds within their bands. Many problems in the husbandry of social animals such as horses, are due to the fact that the limits of their adaptive abilities are exceeded. Evidence suggests that the fundamental social characteristics of domestic horses have remained relatively unchanged. The social structure, social strategies and social interactions were investigated (3 non-consecutive years, 24 hr per day for several weeks) in long term established groups of domestic horses (mares and geldings of all ages) and a few small introduced groups, kept in (semi)natural environments. The general aim was to investigate the social needs of domestic horses. The social life of domestic horses was characterised by long lasting bonds with preferred partners which were established and maintained by allogrooming, play, proximity and dominance behaviours. Bonding partners were mainly found within the same sex-age group, but adult geldings also bonded with sub-adult mares and geldings. Adult mares were clustered in a group, while the other animals formed a second group. Among the adult mares, subgroups according to reproductive state were formed. Individuals regulated their social network by interfering with interactions between other members of the herd, which in itself is complex. An intervention is a behavioural action of one animal that actively interferes with an ongoing interaction between a dyad with the apparent aim of altering that interaction. This was verified by post-hoc analyses of disturbed and undisturbed interactions. Interventions in allogrooming or play were performed significantly more often when at least one member of the initial dyad was a preferred partner of, or familiar to (within the small introduced bands) the intervener. The stronger the preferred association in allogrooming between the intervener and member(s) of the initial dyad, the higher the probability the intervener would displace one initial member and continue allogrooming with the other. Just five behaviours were extracted which reliably reflected the dominance relations among horses. Aggression with the hind quarters was used both offensively and defensively and therefore not suitable as a reliable parameter. Individual dominance relationships were related to social experience. The implications of these findings for horse husbandry were assessed. It is argued that the execution of affiliative behaviours may be rewarding in itself, and therefore always will be a highly motivated behaviour. It is shown that social positive physical interactions (allogrooming, play) with other horses is an ethological need and therefore indispensable in modern husbandry systems. Ethological needs are so important for the animal that husbandry systems that lack the possibilities to execute such behaviours will cause chronic stress. It is concluded that all horses need physical social contact, and that horses, which lack appropriate social learning experiences during ontogeny, may be hampered in their social functioning later in life. Solutions for problems, including dominance problems, in individual social housing and group housing are presented.