Salmonella spp. is a foodborne pathogen present in the pork production chain, leading to potential contamination of end products and causing salmonellosis cases and outbreaks worldwide. The emergence of multidrug-resistant (MDR) Salmonella spp., especially isolates obtained from animal origin food, is a global concern. This study aimed to isolate Salmonella from swine mesenteric lymph nodes (MLN) and to characterize the virulence and antibiotic resistance profiles. MLN samples were obtained from a swine slaughterhouse and subjected to Salmonella spp. isolation. Ten MLN samples were positive and 29 isolates were identified based on PCR (invA and ompC) and serotyping: Derby, Cerro, and Give. Pulsed-field gel electrophoresis allowed to group the isolates based on their serotypes, resulting in three major clusters. All isolates presented the virulence-related genes pefA, sipA, sopB, spaN, and pagC. Relatively high numbers of Salmonella spp. were resistant to neomycin, polymyxin B, ciprofloxacin, tetracycline, and nalidixic acid. Furthermore, 25 isolates presented simultaneous resistance to three or more antibiotic classes, being characterized as MDR. The obtained results confirmed the relevance of swine as reservoirs of Salmonella spp. in the pork production chain and demonstrated the MDR profiles of isolates. Proper control and surveillance are required to avoid the contamination of end products.

中文翻译：

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从猪淋巴结中分离出的沙门氏菌的多药耐药性和毒力特征

沙门氏菌属 沙门氏菌是猪肉生产链中存在的食源性病原体，导致最终产品的潜在污染，并在全球引起沙门氏菌病病例和爆发。耐多药 (MDR)沙门氏菌属的出现，尤其是从动物源性食品中分离出来的菌株，是全球关注的问题。本研究旨在从猪肠系膜淋巴结 (MLN) 中分离沙门氏菌，并表征毒力和抗生素耐药性特征。MLN 样品是从猪屠宰场获得的，并受到沙门氏菌属的影响。隔离。10 个 MLN 样本呈阳性，基于 PCR 鉴定出 29 个分离株（invA和ompC) 和血清分型：Derby、Cerro 和 Give。脉冲场凝胶电泳允许根据其血清型对分离株进行分组，产生三个主要簇。所有分离株均呈现毒力相关基因pefA、sipA、sopB、spaN和pagC。沙门氏菌数量相对较高。对新霉素、多粘菌素 B、环丙沙星、四环素和萘啶酸有抗药性。此外，25 个分离株同时对三种或更多抗生素类别表现出耐药性，被称为 MDR。获得的结果证实了猪作为沙门氏菌宿主的相关性属 在猪肉生产链中，并展示了分离株的 MDR 谱。需要进行适当的控制和监督，以避免最终产品受到污染。