奶牛分娩风险预警与防控

Early warning, prevention and control of risks in delivery for dairy cows

对宁夏地区近3年规模化奶牛场6 000余头奶牛的围产期疾病进行跟踪调查,根据奶牛预产期前1周内的临床征兆分析其在分娩中和产后可能发生重大致死、致残、高发疾病的风险。奶牛在分娩中发生的主要疾病是产程延长、难产、产道损伤和产道感染,犊牛死亡或犊牛拉伤;产后母牛容易发生胎衣不下、急性产道性败血症、产后瘫痪、皱胃移位、子宫炎、酮血病,前胃迟缓、急性坏死性肠炎和腹泻等疾病;新生犊牛易发生的疾病主要是腹泻、肺炎。调查发现:产前1周发现有分娩风险信号的母牛,产后60 d内病死淘汰率明显高于非风险分娩牛;奶牛产前1周出现肥胖、瘤胃空虚、腹围异常增大、腹下严重水肿、年龄偏大、走路摇摆等信号,则在分娩中存在着高风险。采取适当的干预防控措施,可降低分娩高风险牛的分娩风险和产后疾病,从而降低经济损失。

A follow-up survey was conducted on perinatal diseases of more than 6,000 dairy cows in large-scale dairy farms in the Ningxia area in the past three years, and analysis was performed of the clinical signs within one week before the expected date of delivery of the cows to identify the severe risks of death, disability, and high incidence of diseases of cows during and after delivery. The main risks that happen to dairy cows during delivery are prolonged labor, dystocia, birth canal injury, birth canal infection, and calf death or calf strain. Postpartum cows are prone to placenta retention, acute birth canal sepsis, postpartum paralysis, and abomasum displacement;and to other diseases such as metritis, ketosis, anterior stomach delay, acute necrotizing enteritis, and diarrhea. Newborn calves are prone to diseases such as diarrhea and pneumonia. The survey found that cows with signs of delivery risks found one week before delivery suffered a mortality rate within 60 days after delivery which was significantly higher than that of non-risk delivery cows. Dairy cows with symptoms of obesity, rumen empty, abnormally enlarged abdominal circumference and lower abdomen within one week before delivery, and signs of severe edema, older age, and wagging walking, are at high risk during delivery. Therefore, adoption of appropriate preventive and control measures can effectively lower the risks of delivery and postpartum diseases of high-risk cows, thereby reducing economic losses.