The behaviour pattern of lambs after castration using a rubber ring and/or castrating clamp with or without local anaesthetic.

AIMS: To determine if individual behaviours may be used to compare the distress caused by the different methods of castration.
METHODS: A controlled experiment in which the behaviour pattern of 174 lambs given one of twenty treatments (six ring, five clamp plus ring and four clamp castration with a variety of local anaesthetic placements plus five control treatments) were monitored for 4 hours from about 5 seconds after treatment.
RESULTS: The contrast between the behaviour patterns of lambs castrated by different methods with or without local anaesthesia and control groups allowed the identification of individual behaviours stimulated by the different methods of castration. After ring castration there was an increase in restlessness, in contrast to clamp castration, which had no obvious individual behaviour associated with it during the 4 hours after treatment. Clamp plus ring castration resulted in a behaviour pattern similar to those caused by ring castration alone.
CONCLUSIONS: Individual behaviours can only be used to compare the distress caused by different methods of castration if the methods stimulate similar behaviours. The distress which occurs after ring or clamp castration cannot be compared using behavioural observations because the two techniques stimulate different types of behaviour.