The Welfare of Sheep: Review of Recent Literature

or Summary of Interesting Publications Boivin,X., Nowak,R., Le Neindre,P., Tournadre,H. , Le Neindre,P. 1997. Discriminationbetween shepherds by lambs reared under artificial conditions. Journal of AnimalScience 75:2892-2898. Few experiments have demonstrated that the identity of a stockman can play a role in the reaction of farmungulates toward a human. In this study, the researchers looked at the ability of 32 lambs rearedartificially in groups of four to discriminate between their shepherd and an unknown shepherd. Half ofthe lambs were bottle fed in isolation by one shepherd during the first 3 weeks while the other half wasfed alternately by three shepherds. The lambs were then tested at 3, 6 and 14 weeks of age to find out theeffect of rearing conditions on the response to isolation and to reunion with the known or an unknownshepherd. Some of the behaviours measured were the number of vocalizations, number of squarescrossed, latency to interact with the shepherd, and time spent interacting with the shepherd. During thetest performed at 3 weeks, lambs interacted more quickly, interacted longer and vocalized less with theknown shepherd than with the unknown shepherd. These behaviours were noted more at 3 and 6 weeksthan at 14 weeks. These results showed that lambs can distinguish among different people and that fearresponses to isolation are reduced more when a known shepherd is present. Also, this ability todiscriminate among handlers was most apparent at week 3 and 6 and by week 14 had disappeared.Therefore, knowledge of the shepherd in early age can greatly affect a lamb's reactions to that shepherdand this could help the usual shepherd handle the lambs and ease the fear and stress in the lambs. Graham,M.J., Kent,J.E., Molony,V. 1997. Effects of four analgesic treatments on thebehavioural and cortisol responses of 3-week-old lambs to tail docking. The VeterinaryJournal 153:87-97. Tail docking is regularly practiced to reduce the risk of blowfly strike. However, there is concernover the welfare of the animals undergoing this procedure as many studies have indicated thatall commonly used methods result in signs of acute distress. In this study, the behavioural and cortisol responses of lambs were used to determine which of three methods of tail docking(rubber ring, Burdizzo and rubber ring combined, or heated docking iron) produced the leastsigns of pain in the first 3 hours after use and which of four anaesthetics (1.0 ml bupivacainesubcutaneously, 0.5 ml bupivacaine epidurally, a topical cold analgesic spray or diclofenac 1.5mg kg) was most effective in reducing these signs. It was found that compared with the rubberring alone, the application of the Burdizzo crush as well as the ring reduced the incidence ofactive behaviours, the cortisol response and the time spent in abnormal positions. Docking witha heated cautery iron produced the least changes in behaviour and cortisol levels, but that doesnot mean that this method is the best as it can produce lesions that can lead to chronicinfections. Subcutaneous injection of the local anaesthetic at the ring site just before applicationof the ring was the most effective means of reducing the pain from this method. From thesefindings, it was concluded that if a practical means can be found to produce a local anaestheticquickly and without the use of needles, then the method of ring tail docking could be morehumane. Kent,J.E., Molony,V., Graham,M.J. 1998. Comparison of methods for the reduction of acutepain produced by rubber ring castration or tail docking of week-old lambs. TheVeterinary Journal 155:39-51. The rubber ring method for castration and tail docking of lambs is widely used, but has been shown toproduce considerable acute pain in all ages of lambs up to six weeks. In this study, a bloodless castratorwas compared with an injection of local anaesthetic in their ability to reduce pain for rubber ringcastration. As well, the effectiveness of a needleless injection technique was compared with aconventional injection. The results showed that for castration, the most effective method in reducing painwas the application of the ring, followed by an injection of local anaesthetic and then by the application ofthe bloodless castrator. For rubber ring tail docking, the most effective method was a needleless injectionof local anaesthetic without the use of the bloodless castrator. Injections of local anaesthetic by either theneedle or the needleless injector were effective, but the needleless injection was safer, quicker and easierto apply. From the results, it was concluded that the injection of a local anaesthetic immediately after theapplication of the rubber ring effectively reduced, but did not completely eliminate, the acute painproduced by this method of castration and tail docking. Knowles,T.G. 1998. A review of the road transport of slaughter sheep. Veterinary Record143:212-219. This paper reviews the past and recent scientific literature relevant to the road transport of slaughtersheep. Recommendations for the best practices are given and areas that require further work are alsoidentified. When conditions are difficult, individual animals use various methods to try to counteract anyadverse effects of those conditions. This may involve changes in behaviour and shifts in physiologicalvariables away from values that are typically considered to be "normal". There are many types ofmeasurements that can be used to assess the effects of transport. They are mortality, injury and disease,immune function, meat quality, weight loss, the levels of muscle and liver glycogen, plasma free fattyacids, urea, and B-hydroxybutyrate, and blood measurements of total protein, albumin, packed cellvolume and osmolality. The death or injury of an animal is an extreme but useful measurement ofwelfare. However, mortality rates and levels of injuries among lambs are low when compared with thoseof other farmed species and considering the numbers of animals transported. Before being loaded onto atruck, sheep can show signs of stress due to previous handling. Loading and the initial few hours oftransport cause a sharp increase in heart rate, muscle activity and plasma hormone concentrations, but these factors decrease after 9 hours. Transport can involve long periods without food or water. One resultis a loss of liverweight and a reduced carcass weight. During long journeys, a mid-transport lairage stopfor food, water and rest should provide a chance for recovery from the effects of the journey before it isresumed. However, short rest periods do not seem to be of real benefit and could even be detrimental.There is little experimental work on which to base stocking densities, but evidence does suggest thatanimals require space in which to make positional adjustments in order to maintain their balance. Theauthor concluded that much work still needs to be done in the area of sheep transport. Some of the topicsthat need to be looked at are appropriate resting periods and feed requirements, the effects of stockingdensity on injury and loss of balance and the circumstances under which high mortality occurs withinindividual loads.