Abstract: Many horse owners tend to group horses according to gender, in an attempt to reduce aggressive interactions and the risk of injuries. The aim of our experiment was to test the effects of such gender separation on injuries, social interactions and individual distance in domestic horses. A total of 66 horses were recruited from 4 different farms in Norway and Denmark and divided into six batches. Within each batch, horses were allotted into one mare group, one gelding group and one mixed gender group, with most groups consisting of three or four animals. After 4-6 weeks of acclimatisation, a trained observer recorded all social interactions using direct, continuous observation 1 h in the morning and 1 h in the afternoon for three consecutive days. Recordings of the nearest neighbour of each horse were performed using instantaneous sampling every 10 min. The horses were inspected for injuries before grouping, day 1 after grouping and after 4-6 weeks. No significant effect of gender composition was found on social interactions (P > 0.05), spacing (P > 0.07) or injuries (P > 0.23). Eighty percent of all aggressive interactions recorded were threats, not involving physical contact. Horses with the smallest space allowance showed the highest mean number of aggressive interactions (28.6 ± 6.1 interactions per 6 h) compared to the mean of all the other batches (8.3 ± 1.0 interactions per 6 h). Very few injuries were found and most were superficial. In conclusion, gender composition does not seem to have any effect on aggression level, spacing or injuries. However, the early social experience of horses, management of feeding and space allowance probably represents more important factors for successful group housing of domestic horses.

Abstract: The aim of this study was to investigate the use of items intended to provide enrichment during turnout, both for individual and group kept horses in an attempt to reduce the amount of passive behaviours. The study was divided into two parts, where study 1 involved eight horses rotated through eight individual paddocks, each containing one of seven enrichment items and one paddock being kept without item, functioning as a control. The horses' item-directed behaviours; passive behaviours or other non-item related activities were scored using instantaneous sampling, every minute for 1h at the beginning and the end of the turnout period. Study 2 involved six horse groups (3-6 horses) and the same scoring methods and ethogram as in study 1. The four items that the horses interacted the most with during study 1 (straw STRA, ball filled with concentrates CBALL, branches BRAN and scratching pole POLE) are investigated in study 2. In addition, the amount of social interactions was recorded. Both horses kept individually (P<0.05) and in groups (P<0.0001) performed significantly more item-directed behaviours towards edible items like STRA and CBALL than other objects. There was, however, no overall relation between the numbers of item-directed behaviours and the number of passive behaviours observed, indicating that the enrichment items did not alone reduce the amount of passive behaviours during turnout periods. Such a reduction was, however, only apparent when horses spent more time eating green leaves growing on the paddock surface (R=-0.97 study 1, R=-0.67 study 2, P<0.0001). Access to STRA in group kept horses also seemed to reduce the amount of agonistic behaviours (P<0.0001). In conclusion, if grass is not available in paddocks, the provision of roughage reduces the amount of passive behaviours in singly kept horses and it also reduces the risk of agonistic interactions between horses kept in group.

Abstract: Social-related behaviour of N'dama and West African Shorthorn (WASH) cattle grazing together was studied over 10 consecutive days. Dominance was not related to age, liveweight or leadership when the animals were led into a weighing scale or into and out of the experimental paddock. Dominance had no influence on the use of shade, on drinking frequency or on grazing time, it was, however, positively associated with time spent ruminating and idling and with the frequency of allogrooming. Forced leadership into a weighing scale was negatively correlated (Spearmans rank correlation (rs=-0.69, P<0.05) with liveweight while voluntary leadership, out of the experimental paddock (rs=0.85, P<0.01) and into the experimental paddock (rs=0.76, P<0.05), was positively correlated with liveweight. Voluntary leadership also positively and significantly (P<0.01) influenced the frequency of visits to the water trough. All measures of leadership were significantly but negatively correlated with frequency of social association (close contact) between cows. N'dama were more aggressive than WASH and had higher dominance values. There was a slight tendency for WASH to associate more with their peers than N'dama with their peers. Social behaviours such as allogrooming were low and rubbing and sniffing absent in both breeds.

Abstract: Horse trailers are a common form of transportation for horses and ponies and often require the animal to travel alone or with a single companion. The current study investigated the effect of transporting horses alone, in company or with an acrylic safety mirror (measuring 81cm61.5cm) that provided surrogate companionship. The behavioural and physiological responses of 12 mature horses during a 30-min journey by trailer under the three treatments were compared. Behaviours (vocalisation, eating, head-tossing, pawing, and head-turning) were recorded. In order to assess circulatory changes that occur as part of the response to transport, heart rate (HR), rectal (Tr) and ear-pinna (Tp) temperatures were recorded. When travelling with a live companion significantly less time was spent vocalising (p<0.001), head-turning (p<0.001), head-tossing (p<0.01) and pawing (p<0.01); eating behaviour increased (p<0.05). Physiological responses (increases in HR and Tr and decreases in Tp) were also significantly reduced when travelling with a live companion (p<0.01). Travelling with the mirror did not significantly affect physiological responses compared with travelling alone, but the rise in Tr and fall in Tp was reduced (p=0.052 and p=0.051, respectively) and can be considered a trend. When travelling with a mirror significantly less time was spent turning the head (p<0.01), vocalising (p<0.05) and head-tossing (p<0.05); eating behaviour increased (p<0.05). The only significant difference between travelling with a live companion and a mirror was that the time spent turning the head round was less with a live companion (p<0.05). The provision of surrogate companionship in the form of a mirror was found to be preferable to travel alone, but where possible a live companion is recommended. Isolation during transportation was found to suppress feeding behaviour. Although peripheral blood flow (Tp) has been used to assess transport stress in other species it has not previously been used in the horse. Further evaluation of this non-invasive measure is now required.

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.