Abstract
PICO QUESTION: In lambs less than 7 days old undergoing castration with rubber rings does administration of local anaesthetic compared to no local anaesthetic result in a reduction of pain-related behaviours? CATEGORY OF RESEARCH: Treatment. NUMBER AND TYPE OF STUDY DESIGNS REVIEWED: Six studies were appraised; all were controlled clinical or field trials. STRENGTH OF EVIDENCE: Moderate. OUTCOMES REPORTED: Local anaesthetic administered to lambs castrated with rubber rings resulted in the demonstration of fewer pain related behaviours and also diminished the increases in plasma cortisol in the immediate post-castration period when compared to lambs castrated without local anaesthetic. Local anaesthetic administered at least 15 minutes before rubber ring castration may significantly reduce behavioural signs of pain and plasma cortisol changes. CONCLUSION: In lambs less than 7 days old undergoing castration with rubber rings, local anaesthetic reduces markers of pain when compared to lambs castrated without local anaesthetic.