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    Studies of castration and tailing in young lambs [microform] : influences of different methods on acute distress responses : a thesis in partial fulfilment of the requirements for the degree of Master of Science in physiology at Massey University
    (Massey University, 1991) Lester, Stephen John
    An investigation of the acute effects of several methods (rubber rings, knife and docking iron) of castrating and tailing 4 to 5 week old lambs was performed. The investigation consisted of a study of certain anatomical aspects of the sites of castration and tailing, experimental validation of the behavioural responses as indices of distress, ranking of the various methods of castration and tailing according to the acute responses and testing of the effects of handling on lambs castrated plus tailed with the knife The innervation of the external genitalia and the tail was described and the pattern of innervation was discussed with respect to castration and tailing. The behaviour elicited by castration and tailing was dependent upon the method used. Following rubber ring application the behaviours exhibited were increased activity, increased recumbency of which a high proportion was lateral, and these behaviours were associated with elevated plasma Cortisol concentrations and are therefore suggested to be indicative of distress. After use of the knife or the docking iron abnormal standing/walking behaviour was associated with elevated plasma Cortisol concentrations and therefore appeared to indicate distress. The behavioural and plasma Cortisol responses continued beyond the 4 hour observational period of the first experiment so a second experiment was performed. It demonstrated that the response to castration plus tailing with the knife approached completion at 8 hours. Handling of lambs to effect blood sampling did not appear to significantly affect the response. Ranking of the methods of castration plus tailing, castration only and tailing only showed that the use of the knife was apparently more distressing than any other procedure. Apparently less distressing than the use of the knife but similar to each other were castration plus tailing with the rings, castration only with the ring, short-scrotum plus tailing with the rings and castration with the ring plus tailing with the docking iron. Tailing only with the ring and tailing only with the docking iron were apparently as distressing as handling with jugular venipuncture, although it is suggested that the quality of the distress apparently experienced would have been different. Thus in order to minimise the acute effects on lambs, there is evidence that the best methods are as follows. 1. For castration plus tailing: castration plus tailing with the rubber rings, short-scrotum plus tailing with the rubber rings or castration with the rubber ring plus tailing with the docking iron. 2. For castration only: castration only with the rubber ring. 3. For tailing only: tailing only with the rubber ring or the docking iron. However there are other factors to be considered in conjunction with the above recommendations, and these are discussed.
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    Alleviation of the distress caused by ring castration plus tailing of lambs and dehorning of calves : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physiology at Massey University
    (Massey University, 1999) Sutherland, Mhàiri Anne
    There is increasing social and economic pressure to improve the welfare of animals in our care. In the present study plasma cortisol concentrations were measured to assess the pain-induced distress caused by ring castration plus tailing in lambs and dehorning in calves and the extent to which the distress caused by these procedures can be reduced by using different alleviation strategies. Local anaesthetic injected into the neck of the scrotum just before ring application significantly reduced the cortisol response to ring castration plus tailing in lambs, but local anaesthetic injected into the testes just after ring application only marginally reduced this response. A castration clamp was applied across the full width of the scrotum of lambs for 6 or 10 seconds after ring castration plus tailing to disable the innervation from the scrotal area. The application of the castration clamp for 6 seconds after placement of the ring did not reduce the cortisol response to ring castration plus tailing, whereas application for 10 seconds slightly, but significantly, reduced the peak cortisol concentration. Healing of the castration wound was not complicated by the application of the castration clamp after ring castration plus tailing. Therefore injecting local anaesthetic into the neck of the scrotum just before ring castration plus tailing significantly alleviates the pain-induced distress associated with ring castration plus tailing, but applying the castration clamp in combination with ring castration plus tailing has little benefit. Local anaesthetic given prior to dehorning virtually abolishes the cortisol response to dehorning for the duration of action of the local anaesthetic, but once the local anaesthetic wears off cortisol concentrations increase resulting in a delayed cortisol response equivalent to the overall cortisol response to dehorning when local anaesthetic is not used. This delayed cortisol response is thought to be stimulated by inflammation-related pain. The non-steroidal anti-inflammatory drugs (NSAIDs) ketoprofen and phenylbutazone and an endogenous cortisol surge stimulated by iniecting ACTH were used to assess whether this delayed cortisol response is associated with inflammation-related pain. Local anaesthetic (5 hour duration of action) plus ketoprofen given prior to scoop dehorning marginally reduced the delayed cortisol response observed once the local anaesthetic wore off, but giving local anaesthetic and phenylbutazone prior to dehorning had no significant effect on this delayed cortisol response. The antinociceptive action and a greater anti-inflammatory potency of ketoprofen compared to phenylbutazone may explain why ketoprofen was more effective than phenylbutazone in reducing this delayed cortisol response. ACTH plus local anaesthetic given prior to dehorning only marginally reduced the delayed cortisol response observed once the local anaesthetic wore off, suggesting that the delayed cortisol response seen when the local anaesthetic wears off is not due primarily to inflammation-related pain Giving local anaesthetic prior to dehorning and cauterising the amputation wounds prevented the delayed cortisol response after the local anaesthetic wore off and significantly reduced the overall cortisol response to dehorning. Thus, in the present study long acting local anaesthetic (5 hour duration of action) in combination with NSAIDs had minimal alleviating effects on the pain-induced distress caused by dehorning compared to local anaesthetic alone, but local anaesthetic and cautery provided effective pain-relief.