Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa 50011, USA.
Foodborne Pathog Dis. 2010 Jul;7(7):795-800. doi: 10.1089/fpd.2009.0459.
The aim of this study was to assess the value of deep systemic sub-iliac lymph nodes collected at slaughter as predictors of Salmonella prevalence in live hogs. An observational study was conducted on 24 farms from September 2006 to February 2009. At least one cohort of market-weight pigs was visited for each farm. Within each cohort, 30 farm fecal samples on farm and 30 sub-iliac lymph nodes from matched pigs at slaughter were collected. Samples were cultured for Salmonella enterica and serotyped by conventional methods. Overall, 3.4% (51 of 1490) of farm feces and 0.06% (1 of 1739) of sub-iliac lymph nodes were Salmonella positive; 71.4% (15 of 21) of farms had at least one positive fecal sample, and 4.2% (1 of 24) had at least one positive sub-iliac lymph node. The median within-farm prevalence of Salmonella in farm fecal samples was 1.7%, ranging from 0% to 38.3%; for sub-iliac lymph nodes the median was 0%, ranging from 0% to 1.1%. The median within-cohort prevalence in farm fecal samples was 0%, ranging from 0% to 43.3%; for sub-iliac lymph nodes the median was 0%, ranging from 0% to 4%. The predominant serotype detected was Derby, followed by Anatum and Typhimurium (Copenhagen). Salmonella Braenderup was recovered from the sub-iliac lymph node. The low detection rate of Salmonella in sub-iliac lymph nodes (0.06%) limits its usefulness as a dependable predictor of Salmonella contamination originating on farm (3.4%).
本研究旨在评估在屠宰时收集的深部系统性骼下淋巴结作为活猪沙门氏菌流行率预测指标的价值。2006 年 9 月至 2009 年 2 月进行了一项观察性研究。对每个农场至少访问了一个市场体重猪群。在每个猪群中，收集了 30 个农场粪便样本和 30 个匹配屠宰猪的骼下淋巴结。采用传统方法对样本进行了沙门氏菌培养和血清分型。总的来说，3.4%（1490 份粪便中的 51 份）和 0.06%（1739 份骼下淋巴结中的 1 份）的农场粪便和骼下淋巴结样本为沙门氏菌阳性；71.4%（15 个农场）至少有一个阳性粪便样本，4.2%（1 个农场）至少有一个阳性骼下淋巴结样本。农场粪便样本中沙门氏菌的农场内流行率中位数为 1.7%，范围为 0%至 38.3%；骼下淋巴结的中位数为 0%，范围为 0%至 1.1%。农场粪便样本中每批流行率的中位数为 0%，范围为 0%至 43.3%；骼下淋巴结的中位数为 0%，范围为 0%至 4%。检测到的主要血清型为德比、安纳图姆和肠炎沙门氏菌（哥本哈根）。从骼下淋巴结中分离出沙门氏菌布伦达普。骼下淋巴结中沙门氏菌的低检出率（0.06%）限制了其作为农场污染（3.4%）可靠预测指标的实用性。
