Asia Pacific Centre for Animal Health, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, Victoria, Australia.
PLoS One. 2018 Jul 19;13(7):e0201031. doi: 10.1371/journal.pone.0201031. eCollection 2018.
The transmission of Salmonella enterica within a vertically integrated poultry operation was investigated longitudinally over an 18-month period (2013-2014). Thirty six percent of all samples collected (1503 of 4219) were positive for salmonellae with seven Salmonella enterica subsp. enterica serovars, and one Salmonella enterica subsp. salamae serovar detected. Both Salmonella enterica subsp. enterica serovars Infantis and Typhimurium were detected in all locations sampled. Salmonella Typhimurium was the most frequently detected serovar (63% of serotyped samples) with 8 phage types (PT) and 41 multiple-locus variable-number tandem-repeats analysis (MLVA) profiles identified. The most frequently identified phage types were PT135a and DT135. A total of 62 PT/MLVA combinations were observed. MLVA profiles 03-14-10-09-525 and 03-15-11-11-525 were the most frequently identified and 83% of the isolates shared at least one MLVA profile with an isolate from another phage type. The use of phage typing and MLVA profiling, on their own or in combination, were insufficient to understand the complexity of the epidemiological relationships between locations within this production system. Despite the high level of apparent diversity, cluster analysis was unable to differentiate the transmission pathways of all S. Typhimurium variants detected within the integrated enterprise. Using additional epidemiological information, the parent breeder rearing site was identified as the most likely point of introduction of two S. Typhimurium isolates into the production system with subsequent dissemination to the broiler flocks via the hatchery. This complexity is unable to be resolved in the absence of intensive sampling programs at all generations of the production system.
2013-2014 年，对一个垂直整合的家禽养殖场内的沙门氏菌传播进行了为期 18 个月的纵向调查。在所采集的 4219 个样本中，有 36%（1503 个）呈沙门氏菌阳性，检测到 7 种沙门氏菌亚种。肠亚种血清型和 1 种沙门氏菌亚种。salamae 血清型。所有采样地点均检测到肠亚种沙门氏菌血清型婴儿和 Typhimurium。检测到的血清型 Typhimurium 是最常见的血清型（63%的定型样本），有 8 种噬菌体型（PT）和 41 种多位点可变数串联重复分析（MLVA）图谱。最常见的噬菌体类型是 PT135a 和 DT135。共观察到 62 种 PT/MLVA 组合。MLVA 图谱 03-14-10-09-525 和 03-15-11-11-525 是最常见的，83%的分离株与另一种噬菌体型的分离株至少有一个 MLVA 图谱共享。单独或组合使用噬菌体分型和 MLVA 图谱分析不足以了解该生产系统内各地点之间的流行病学关系的复杂性。尽管存在高度的明显多样性，但聚类分析无法区分在综合企业内检测到的所有 Typhimurium 变体的传播途径。使用额外的流行病学信息，确定种鸡繁殖场是两个 Typhimurium 分离株进入生产系统的最有可能的引入点，随后通过孵化场传播到肉鸡群。在没有对生产系统的所有世代进行密集采样计划的情况下，这种复杂性无法得到解决。
