van Dorp R T, Martin S W, Shoukri M M, Noordhuizen J P, Dekkers J C
Department of Animal and Poultry Science, University of Guelph, Ontario.
Can J Vet Res. 1999 Jul;63(3):185-92.
Data recorded in a herd health management system were obtained from 32 registered Holstein dairy herds from British Columbia. Frequencies of disease were described, and the effect of herd, age, year, season, and the interrelationships between diseases within a lactation on the occurrence of disease were evaluated. Lactational incidence rates were computed for diseases with a short period of risk (ie, udder edema, milk fever, retained placenta, metritis, displaced abomasum, and ketosis), whereas for diseases with a longer period of risk (ie, cystic ovaries, mastitis and stable footrot), incidence densities were calculated. Overall, the disease incidence was low and showed an increase in frequency by year, which we attributed to more observing and complete recording by the owner, rather than an actual increase in disease incidence. Most diseases occurred early in lactation and their frequency increased with lactation number; the exception was udder edema, which occurred mainly during the first 2 lactations. An informal path model of disease interrelationships was made conditional on herd. Based on the results we inferred 2 independent pathways: one started by udder edema, and the other by milk fever. Udder edema was directly associated with mastitis occurrence from 0 to 30 d in lactation, metritis, and cystic ovaries. Mastitis from 0-30 d in lactation increased the risk of both mastitis from 31-150 d in lactation and cystic ovaries. Both of these increased the risk of late lactation mastitis. Milk fever was directly related with displaced abomasum, which increased the risk of footrot. In general, diseases that occurred in early lactation tended to increase the risk of other diseases later in lactation.
从不列颠哥伦比亚省的32个注册荷斯坦奶牛场的畜群健康管理系统中获取数据。描述了疾病的发生频率，并评估了畜群、年龄、年份、季节以及泌乳期内疾病之间的相互关系对疾病发生的影响。对于风险期较短的疾病（即乳房水肿、产乳热、胎衣不下、子宫炎、皱胃移位和酮病）计算泌乳发病率，而对于风险期较长的疾病（即卵巢囊肿、乳腺炎和蹄叶炎）计算发病密度。总体而言，疾病发病率较低，且发病率逐年上升，我们将其归因于畜主观察更仔细、记录更完整，而非疾病实际发病率增加。大多数疾病发生在泌乳早期，且发病率随泌乳次数增加；例外的是乳房水肿，主要发生在前两胎泌乳期。基于畜群构建了疾病相互关系的非正式路径模型。根据结果，我们推断出两条独立路径：一条始于乳房水肿，另一条始于产乳热。乳房水肿与泌乳0至30天的乳腺炎、子宫炎和卵巢囊肿的发生直接相关。泌乳0至30天的乳腺炎增加了泌乳31至150天的乳腺炎和卵巢囊肿的风险。这两者都增加了泌乳后期乳腺炎的风险。产乳热与皱胃移位直接相关，而皱胃移位增加了蹄叶炎的风险。一般来说，泌乳早期发生的疾病往往会增加泌乳后期其他疾病的风险。
