Campylobacter spp. are the leading causes of bacterial human gastroenteritis worldwide; being poultry farms the main source of infections. In order to obtain information on prevalence and diversity of Campylobacter-infected flocks in the North of Spain, fourteen farms were studied between autumn and spring in 2014 and 2015, respectively. Moreover, virulence genes involved in pathogenicity and antimicrobial resistance were investigated. A survey about preventive hygiene practices at farms was performed to determine the risky practices that could contribute to the presence of Campylobacter in this step of the poultry food chain. Testing the presence of Campylobacter spp. showed 43 % of the farms were positive during autumn, whereas only 31 % were positive in spring. A very high prevalence within-flock was observed (43.1 % to 88.6 %) and C. jejuni was the most prevalent species in both periods. Genotyping by pulsed field gel electrophoresis (PFGE) showed a high heterogeneity among farms (309 isolates clustered into 21 pulsotypes). Virulence genes were present in all C. jejuni isolates while cdtA and cdtC were absent in C. coli. On the contrary, the latter showed higher antimicrobial resistance than C. jejuni. This study suggests that environment might be one of the main sources for Campylobacter transmission, as water supply seemed to be a clear cause of the contamination in a specific farm. However, in other farms other environmental factors contributed to the contamination, confirming the multifactorial origin of Campylobacter colonization in broilers. Therefore, biosecurity measures in farms are crucial to reduce Campylobacter contamination, which may have important implications for human and animal health.

中文翻译：

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西班牙家禽养殖场在两个季节分离的弯曲杆菌属的基因型，毒力基因和抗药性。

弯曲杆菌属。是全世界细菌性人类胃肠炎的主要原因；成为家禽养殖场的主要感染源。为了获得有关西班牙北部弯曲杆菌感染鸡群的流行和多样性的信息，分别在2014年和2015年的春季和春季之间研究了14个农场。此外，还研究了致病性和抗菌素耐药性相关的毒力基因。对农场的预防性卫生习惯进行了一项调查，以确定在禽类食物链这一步骤中可能导致弯曲杆菌存在的危险习惯。测试弯曲杆菌属的存在。结果显示，秋季有43％的农场呈阳性，而春季只有31％。观察到羊群和鸡群的患病率很高（43.1％至88.6％）。空肠是两个时期中最流行的物种。脉冲场凝胶电泳（PFGE）的基因分型显示了农场之间的高度异质性（309个分离株聚集成21个脉冲型）。在所有空肠弯曲菌中都存在毒力基因，而在大肠杆菌中却没有cdtA和cdtC。相反，后者显示出比空肠弯曲杆菌更高的抗药性。这项研究表明，环境可能是弯曲杆菌传播的主要来源之一，因为供水似乎是特定农场污染的明显原因。但是，在其他农场中，其他环境因素也造成了污染，这证实了肉鸡弯曲杆菌定植的多因素起源。因此，农场的生物安全措施对于减少弯曲杆菌污染至关重要，