Evaluation of a novel desensitising device (ClipFitter) for castration and tail-docking of lambs to reduce pain assessed by quantitative and qualitative behavioural methods.

Castration and tail-docking using rubber rings (RR) are legally permitted in GB without use of anaesthesia or analgesia in lambs aged less than 7 days, despite causing significant pain. A novel device, ClipFitter, applies a disposable plastic clip to the scrotum or tail whilst clamping the tissue to crush the nerves. This study tested the efficacy of ClipFitter in mitigating lamb pain at castration or tail-docking in twin Scottish Blackface lambs (<7 days old) compared to castration with RR only, castration/tail-docking using RR with local anaesthetic and analgesia, or handling (Handled). The effect of treatment was assessed by quantitative behavioural measurements, Qualitative Behaviour Assessment (QBA), lesion and palpation scores, and time taken to shed necrotic tissues. RR castration, with or without pain relief, caused a significantly greater active pain response and more time spent in abnormal postures than either Handled or ClipFitter castration. Behavioural responses of Handled and ClipFitter-castrated lambs did not differ. QBA data showed significant separation of ClipFitter and Handled lambs from those castrated with RR with or without pain relief. Tail-docking with ClipFitter caused similar behavioural responses to RR tail-docking with pain relief. QBA data from tail-docked lambs did not differ between treatments. Use of ClipFitter caused the necrotic tissue to be shed more quickly than when RR were used. These data support ClipFitter as an alternative method of castration with lower pain responses than RR with or without use of pharmaceutical pain relief.