Department of Population Medicine, University of Guelph, Guelph, ON, Canada N1G 2W1.
Department of Population Medicine, University of Guelph, Guelph, ON, Canada N1G 2W1.
J Dairy Sci. 2019 Oct;102(10):9224-9235. doi: 10.3168/jds.2019-16829. Epub 2019 Aug 1.
High levels of morbidity, mortality, and antimicrobial use are common in the veal industry. For the sustainability of the industry, it is important to address these challenges and determine factors that can be used to improve animal health and welfare. The objectives of this prospective observational cohort study were to describe the health status of calves on arrival at a grain-fed veal facility and determine characteristics that were associated with morbidity and mortality. On arrival, the calves were assessed for health abnormalities, weighed, measured for hip height and length from withers to lumbosacral junction, and had blood collected to determine serum total protein level. Body mass index (BMI) was calculated using weight on arrival divided by the sum of the calf's length from withers to lumbosacral junction and hip height. The calves were observed for 77 d after arrival, during which the producer was responsible for recording all antibiotic treatments and mortality. We built Cox proportional hazard models for morbidity and mortality variables. We created 2 morbidity models: 1 for calves that were treated <21 d after arrival at the facility, and 1 for calves that were treated during the 11 wk at the facility. From January to December 2017, 998 calves were evaluated on arrival at the veal rearing facility. A large proportion (68%) were treated with antibiotics in the first 21 d after arrival. The only explanatory variable in the final <21 d morbidity model was BMI: calves with a higher BMI had a lower hazard of being treated for disease in the first 21 d after arrival. A total of 872 calves (87%) were treated at least once over the 11-wk housing period. A calf arriving with a BMI >371.46 g/cm or a serum total protein between 5.8 and 6.2 g/dL had a lower level of morbidity during the observation period. Over the 11-wk housing period, 74 calves (7.5%) died. Calves that arrived at the facility with a fecal score of 2 or a rectal temperature between 38.9 and 39.1°C had a higher hazard of dying; calves that had a BMI of >371 g/cm were less likely to die than calves that had a BMI <330 g/cm. These results point to the importance of assessing calves on arrival at a veal facility as a measure of identifying those at high risk for morbidity and mortality.
高发病率、高死亡率和高抗生素使用率是小牛肉产业的普遍现象。为了行业的可持续发展，重要的是要解决这些挑战，并确定可以用来改善动物健康和福利的因素。本前瞻性观察队列研究的目的是描述谷物育肥小牛肉设施中小牛到达时的健康状况，并确定与发病率和死亡率相关的特征。到达时，评估小牛的健康异常情况、称重、测量从肩到腰荐关节的臀部高度和长度，并采集血液以确定血清总蛋白水平。使用到达时的体重除以从肩到腰荐关节和臀部高度的小牛长度之和来计算体重指数 (BMI)。小牛到达后观察 77 天，在此期间，生产者负责记录所有抗生素治疗和死亡情况。我们为发病率和死亡率变量构建了 Cox 比例风险模型。我们创建了 2 种发病率模型：1 种用于在到达设施后 21 天内接受治疗的小牛，1 种用于在设施中接受治疗的 11 周内接受治疗的小牛。2017 年 1 月至 12 月，对 998 头小牛在小牛肉育肥设施到达时进行了评估。很大一部分（68%）在到达后 21 天内接受了抗生素治疗。最后 21 天发病率模型中的唯一解释变量是 BMI：BMI 较高的小牛在到达后 21 天内接受疾病治疗的风险较低。共有 872 头小牛（87%）在 11 周的饲养期内至少接受了一次治疗。到达时 BMI>371.46 g/cm 或血清总蛋白在 5.8 至 6.2 g/dL 之间的小牛在观察期间发病率较低。在 11 周的饲养期内，74 头小牛（7.5%）死亡。到达时粪便评分 2 分或直肠温度在 38.9 至 39.1°C 之间的小牛死亡风险较高；BMI>371 g/cm 的小牛比 BMI<330 g/cm 的小牛死亡风险低。这些结果表明，在小牛肉设施到达时评估小牛作为识别高发病率和死亡率风险的一种措施非常重要。
