USDA-Animal and Plant Health Inspection Service-Veterinary Services, Center for Epidemiology and Animal Health, National Animal Health Monitoring System, Fort Collins, CO 80526-8117; Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523-1678.
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523-1678.
J Dairy Sci. 2019 May;102(5):4704-4712. doi: 10.3168/jds.2018-15728. Epub 2019 Mar 7.
The majority of dairy heifer calves in the United States are destined to be dairy replacements. However, many dairy heifer and bull calves die before 6 mo of age. Of these calves, about 6% (more than 500,000 calves) die at birth or shortly after (i.e., currently termed "stillbirth"). An additional 6% of dairy heifers die during the preweaning period. Death loss in dairy calves is primarily due to stillbirths, failure to adapt to extrauterine life, and infectious disease processes. The reasons for preweaning heifer calf deaths caused by infectious diseases are generally categorized based on easily recognizable clinical signs such as digestive disease/scours or respiratory disease. Most causes of calf death can be mitigated by appropriate preventive care or well-tailored treatments, meaning that the typical death loss percentage could be decreased with better management. Producers could gather information on the circumstances near birth and at death if they had appropriate guidance on what details to record and monitor. This paper provides recommendations on data to collect at the time of birth (i.e., calf birth certificate data). The recording of these critical pieces of information is valuable in evaluating trends over time in morbidity and mortality events in dairy calves. Ideally, necropsy examination would substantially improve the identification of cause of death, but even without necropsy, attribution of cause of death can be improved by more carefully defining death loss categories in on-farm record systems. We propose a death loss categorization scheme that more clearly delineates causes of death. Recommendations are provided for additional data to be collected at the time of death. Recording and analyzing birth certificate and death loss data will allow producers and veterinarians to better evaluate associations between calf risk factors and death, with the goal of reducing dairy calf mortality.
美国大多数奶牛小母牛犊牛都将成为奶牛的替代品。然而，许多奶牛小母牛和公牛犊牛在 6 月龄前死亡。在这些犊牛中，约有 6%（超过 50 万头）在出生时或出生后不久死亡（即目前称为“死产”）。另外 6%的奶牛小母牛在断奶前死亡。奶牛犊牛的死亡损失主要是由于死产、无法适应子宫外生活和传染病过程。由于传染病导致的哺乳期前小母牛犊牛死亡的原因通常根据易于识别的临床症状进行分类，例如消化疾病/腹泻或呼吸道疾病。通过适当的预防保健或精心定制的治疗，可以减轻大多数犊牛死亡的原因，这意味着通过更好的管理，典型的死亡损失百分比可以降低。如果生产者在记录和监测方面有适当的指导，他们可以收集出生时和死亡时的环境信息。本文提供了在出生时收集数据的建议（即犊牛出生证明数据）。记录这些关键信息对于评估奶牛犊牛发病率和死亡率随时间的趋势非常有价值。理想情况下，尸检检查将大大提高对死亡原因的识别，但即使没有尸检，通过在农场记录系统中更仔细地定义死亡损失类别，也可以提高死亡原因的归因。我们提出了一种更清楚地区分死亡原因的死亡损失分类方案。还提供了在死亡时收集更多数据的建议。记录和分析出生证明和死亡损失数据将使生产者和兽医能够更好地评估奶牛犊牛风险因素与死亡之间的关联，从而降低奶牛犊牛的死亡率。
