Factors affecting behavioural disturbances in race-horses

The aim of the present study was to identify relations between stereotyped behaviours (cribbing, weaving and box-walking) and wood-chewing in thoroughbred flat-racing houses (TB) and standardbred trotters and the different management, feeding and training factors to which these horses are exposed. This was obtained by inquiries to all the professional trainers of TB and trottinghorses used for racing in Sweden. The usable response rates were 61% for trotters and 72% for TB representing 4597 trotters from 234 stables and 644 TB from 38 stables. A small field study was carried out to control the validity of the main study which gave results similar to those in the main study. There was a large difference between the two horse categories in the occurrence of behavioural disturbances. The TB had significantly more stereotypies than the trotters (P < 0.001) but there were no differences in the occurrence of wood-chewing. There were several differences in external factors between the horse categories, e.g. trotters had more opportunities for social contacts with other horses, they also had more free time outside the stable and they were trained a shorter time per week than the TB. The TB were given larger amounts of concentrate than the trotters. Wood-chewing within each horse category was explained by the amount of roughage (P < 0.05 in trotters and P < 0.001 in TB) together with other factors. Stereotypies in the TB were explained by: amount of concentrate (positive relation), number of horses per trainer (positive relation) and amount of roughage (negative relation).