Obasanjo I O, Gröhn Y T, Mohammed H O
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Prev Vet Med. 1997 Oct;32(3-4):243-51. doi: 10.1016/s0167-5877(97)00027-5.
An extensive questionnaire was developed and used to collect data from 33 herds that were on the New York State Paratuberculosis Control Program, to study farm factors associated with the presence of Mycobacterium paratuberculosis infection in dairy herds. The results of the last whole herd paratuberculosis fecal culture were used to indicate presence of infection in a herd, with herds having one or more animals positive classified as 'infected'. The average prevalence within herds was 5.2%. Fourteen herds were uninfected and 19 herds had prevalences ranging from 0.7%-28.2%. Data on 31 continuous and 67 categorical risk factors were collected by questionnaire. Ten factors were significantly associated with prevalence risk of infection in the univariable logistic regression. These factors were: the type of farm operation (commercial/registered or both); earlier diagnosis of the disease before entering the control program; number of clinical cases in the previous year; whether clinical cases were raised or purchased animals; typical signs in clinical cases; exposure of calves 0-6 weeks of age to feces of adult cows; contact of young stock with adult animal feces from using the same equipment to clean the housing for both groups of animals; spreading feces on fields from which forage is later harvested and fed to animals of any age group; what is done with animals that are suspected of having paratuberculosis or test positive on culture; and frequency of cleaning the cow barn. Stepwise logistic regression was used to determine the significance of each risk factor while controlling simultaneously for the effect of other factors. The significant factors were the type of farm operation, clinical signs, and exposure of calves to feces of adult cows. Commercial herds, presence of clinical signs typical of paratuberculosis in animals, and exposure of calves 0-6 weeks old to feces of adult cows all indicate a higher likelihood that a herd is infected with M. paratuberculosis.
我们设计了一份详尽的调查问卷，并用于收集来自纽约州副结核病控制项目中33个牛群的数据，以研究与奶牛群中副结核分枝杆菌感染存在相关的农场因素。最近一次全群副结核病粪便培养结果用于表明牛群中感染的存在，有一头或多头动物呈阳性的牛群被归类为“感染”。牛群中的平均患病率为5.2%。14个牛群未感染，19个牛群的患病率在0.7%-28.2%之间。通过问卷调查收集了31个连续性和67个分类风险因素的数据。在单变量逻辑回归中，有10个因素与感染的患病率风险显著相关。这些因素包括：农场经营类型（商业/注册或两者兼有）；进入控制项目之前疾病的早期诊断；上一年临床病例的数量；临床病例是饲养的动物还是购买的动物；临床病例中的典型症状；0-6周龄犊牛接触成年母牛粪便的情况；幼畜因使用同一设备清洁两组动物的畜舍而接触成年动物粪便的情况；将粪便撒在后来收获并喂给任何年龄组动物的饲料地上；对疑似患有副结核病或培养呈阳性的动物如何处理；以及牛舍的清洁频率。采用逐步逻辑回归来确定每个风险因素的显著性，同时控制其他因素的影响。显著因素为农场经营类型、临床症状以及犊牛接触成年母牛粪便的情况。商业牛群、动物中存在副结核病典型临床症状以及0-6周龄犊牛接触成年母牛粪便均表明牛群感染副结核分枝杆菌的可能性更高。
