[Prevalence of behavioral disorders in the Swiss horse population].

In the Swiss horse population, the prevalence of conspicuous behaviours (behavioural disorders and stable vices) was recorded with a written questionnaire in a representative survey among 1861 horse yards, and the occurrence of the stereotypic behavioural disorders crib-biting, weaving and boxwalking was analysed with emphasis on their association with horse specific (breed, age, sex) and environmental factors (e.g. housing system, nutrition, management and utilisation). 622 horse yards with a total number of 2536 horses answered to the questionnaire, and conspicuous behaviours were described for 418 horses (16.5%). Thereof, the most common stereotypic behavioural disorders with a potential negative impact on animal welfare, crib-biting, weaving, and/or boxwalking were named for 89 horses (3.5%). Stable vices (e.g. shying, bucking, aggressivity against humans) were noted for 47 horses (1.9%). For 281 horses (11.1%) conspicuous behaviours such as pawing, lip-liking, head shacking, kicking stall were given; these can be categorised as behavioural disorders or as stable vices depending on their intensity and causation. Data analysis data revealed a number of statistically significant associations between genetic factors (breed), housing, management practices, utilisation and the three stereotypies. The strongest influence on the degree of behavioural disorders had the breed as well as the extent of direct social contact with other horses, free movement on pasture, feeding pattern and regular utilisation.