Frankena K, White P W, O'Keeffe J, Costello E, Martin S W, van Grevenhof I, More S J
Quantitative Veterinary Epidemiology Group, Wageningen Institute of Animal Sciences, PO Box 338, 6700 AH Wageningen, The Netherlands.
Vet Rec. 2007 Nov 17;161(20):679-84. doi: 10.1136/vr.161.20.679.
In Ireland, factory surveillance of cattle for gross lesions is an important supplementary method for detecting herds infected with bovine tuberculosis (tb), and in recent years between 27 and 46 per cent of all new herd breakdowns in any year have been detected by this method. The aim of this study was to determine the relative efficiency of factories in detecting lesions among attested cattle slaughtered during 2003 and 2004. National databases were available on animal slaughter, programmes of tuberculin testing for bovine tb and laboratory confirmation of suspected lesions. Factories were ranked according to their submission risk (number of animals submitted with lesions/number of attested animals killed) and confirmation risk (number of animals with laboratory-confirmed lesions/number of animals submitted with lesions), adjusting for the risk profile of the animals slaughtered, including potential confounding factors such as their age and sex, whether they were purchased or homebred, the test history of their herd, the prevalence of bovine tb in the area and the season of slaughter. Approximately 3.7 million cattle were slaughtered in 42 Irish export-licensed factories during the two years. Complete data were available for 2,374,987 animals from 84,510 attested herds in 2845 District Electoral Divisions. Samples from 7398 animals with suspected tb lesions were submitted for laboratory examination; 4767 (64.4 per cent) were positive, 2011 were negative and 620 were inconclusive. The average unadjusted submission risk for all the factories was 22 per 10,000, ranging from 0 to 58 per 10,000. The unadjusted factory confirmation risk (excluding factories that had sent in fewer than 10 lesions) varied between 34.3 per cent and 86.3 per cent. The unadjusted and adjusted submission and confirmation risks were highly correlated, and animal-related factors (including their characteristics and origin) therefore did not contribute to the variations in factory-level submission and confirmation risks.
在爱尔兰，对牛群进行工厂层面的肉眼病变监测是检测感染牛结核病（tb）牛群的一项重要补充方法，近年来，每年通过该方法检测出的新发病牛群占所有新发病牛群的27%至46%。本研究的目的是确定各工厂在检测2003年和2004年经认证屠宰的牛身上病变方面的相对效率。有关于动物屠宰、牛结核病结核菌素检测计划以及疑似病变实验室确诊情况的国家数据库。根据各工厂的送检风险（有病变送检动物数量/经认证屠宰动物数量）和确诊风险（实验室确诊病变动物数量/有病变送检动物数量）对工厂进行排名，并对屠宰动物的风险特征进行调整，包括年龄、性别、是否购买或自繁、牛群检测历史、该地区牛结核病患病率以及屠宰季节等潜在混杂因素。在这两年间，爱尔兰42家获得出口许可的工厂共屠宰了约370万头牛。来自2845个选区的84510个经认证牛群的2,374,98件动物的完整数据可用。对7398头有疑似结核病病变的动物样本进行了实验室检查；4767头（64.4%）呈阳性，2011头呈阴性，620头结果不确定。所有工厂未经调整的平均送检风险为每10000头中有22头，范围为每10000头中0至58头。未经调整的工厂确诊风险（不包括送检病变少于10例的工厂）在34.3%至86.3%之间。未经调整和调整后的送检及确诊风险高度相关，因此与动物相关的因素（包括其特征和来源）并未导致工厂层面送检和确诊风险的差异。
