Funk J A, Harris I T, Davies P R
Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA.
Vet Microbiol. 2005 Apr 25;107(1-2):115-26. doi: 10.1016/j.vetmic.2005.01.006.
In the USA, control of food-borne salmonellosis associated with meat consumption has been predominantly focused at slaughter and processing. It is expected that standards at slaughter and processing will become more stringent, creating pressure to reduce prevalence of Salmonella-positive food animals through on-farm interventions. The aim of this study was to compare traditional fecal culture and the Danish Mix-ELISA (DME) for determination of Salmonella prevalence pre-harvest in swine. In Trial 1, five cohorts of individually identified pigs were longitudinally sampled during the growing period to compare the kinetics of prevalence as estimated by fecal culture and the DME. In Trial 2, the correlation between fecal prevalence and seroprevalence was estimated pre-marketing in 49 groups of pigs. In Trial 1, fecal prevalence and seroprevalence showed similar kinetics, with a tendency of a higher OD% cut-off to more closely approximate fecal prevalence. In Trial 2, correlations between fecal culture and the DME were 0.40, 0.36, 0.43, and 0.43 (p<0.001) for OD% cut-offs > or =10, 20, 30, and 40, respectively. Based on these results, a higher OD% cut-off would be recommended if more approximate estimation of fecal prevalence is desired and longitudinal sampling would be suggested for evaluating the impact of on-farm interventions for Salmonella reduction whether utilizing fecal culture or the DME. Further evaluation of the impact of Salmonella serovar present on farms on seroprevalence and the relationship of on-farm seroprevalence with food safety risk are needed prior to utilizing the DME for pre-harvest Salmonella diagnostics in the US swine herd.
在美国，与肉类消费相关的食源性沙门氏菌病控制主要集中在屠宰和加工环节。预计屠宰和加工环节的标准将变得更加严格，这将促使通过农场干预措施降低沙门氏菌阳性食用动物的流行率。本研究的目的是比较传统粪便培养法和丹麦混合酶联免疫吸附测定法（DME）在猪屠宰前沙门氏菌流行率测定中的应用。在试验1中，对五组单独标识的猪在生长期间进行纵向采样，以比较粪便培养法和DME估计的流行率动态变化。在试验2中，对49组猪上市前粪便流行率和血清流行率之间的相关性进行了估计。在试验1中，粪便流行率和血清流行率呈现相似的动态变化，OD%临界值越高，越接近粪便流行率。在试验2中，OD%临界值分别>或=10、20、30和40时，粪便培养法与DME之间的相关性分别为0.40、0.36、0.43和0.43（p<0.001）。基于这些结果，如果希望更近似地估计粪便流行率，建议采用较高的OD%临界值；如果要评估农场干预措施对降低沙门氏菌的影响（无论使用粪便培养法还是DME），建议进行纵向采样。在美国猪群中，在将DME用于屠宰前沙门氏菌诊断之前，需要进一步评估农场中存在的沙门氏菌血清型对血清流行率的影响以及农场血清流行率与食品安全风险之间的关系。
