Aarhus University, Department of Animal Science, PO Box 50, DK-8830 Tjele, Denmark.
J Dairy Sci. 2012 Oct;95(10):5798-803. doi: 10.3168/jds.2012-5625. Epub 2012 Aug 3.
High mortality among dairy cows constitutes a problem both financially and in relation to animal welfare. Knowledge about causes of death is a fundamental step toward reducing cow mortality. Several studies have evaluated causes of dairy cow deaths. However, the vast majority of studies describing causes of death are based on questionnaires with farmers or veterinarians. It is uncertain to what degree such information is sufficient and reflects the true cause of death or euthanasia. In this study, proximate causes of death were evaluated based on a thorough necropsy of a random sample of 79 Danish dairy cows at an incineration plant. The necropsy was combined with information about the farmer's perception regarding the cause of death and information about disease treatments from the Danish Cattle Database. Pneumonia and locomotor disorders were found to be the most predominant proximate causes of death. Often the death occurred after a prolonged period during which the cow suffered several different disorders, even though this was often not noticed by the farmer. Causes of death stated by the farmers agreed with the necropsy results in 50 to 64% of cases. Information about disease treatments from the Danish Cattle Database agreed with the necropsy results in 34 to 39% of cases. All 3 sources of information about cause of death agreed in only 1 out of 4 cases, and even when the farmer and the disease recordings did agree with the necropsy results, the latter often gave additional information about the cause of death. In many situations, therefore, a necropsy may be a valuable tool when trying to control excessive cow mortality in a herd.
奶牛死亡率高不仅给农场主带来经济损失，也对动物福利造成影响。了解奶牛的死亡原因是降低奶牛死亡率的重要前提。已有多项研究评估了奶牛的死亡原因。然而，绝大多数描述奶牛死亡原因的研究都基于向农场主或兽医发放调查问卷，这些信息是否足够充分，以及能否真实反映奶牛的死亡原因或安乐死原因，仍存在不确定性。在这项研究中，研究人员对丹麦某焚烧厂随机抽取的 79 头奶牛进行了全面尸检，以评估奶牛的直接死亡原因。尸检结果与农场主对奶牛死亡原因的感知、丹麦奶牛数据库中奶牛疾病治疗信息相结合。研究结果表明，奶牛的直接死亡原因主要是肺炎和运动障碍。通常，在奶牛遭受多种不同疾病困扰并经历较长时间的痛苦后，奶牛才会死亡，尽管农场主通常没有注意到这些症状。在 50%至 64%的情况下，农场主报告的死亡原因与尸检结果相符。在 34%至 39%的情况下，丹麦奶牛数据库中的疾病治疗信息与尸检结果相符。在所有 3 种死因信息来源中，只有 1 种情况下能完全一致，即使农场主和疾病记录与尸检结果相符，尸检结果也常常能提供更多关于死亡原因的信息。因此，在许多情况下，对奶牛进行尸检可能是控制牛群过度死亡的有效手段。
