Department of Hygiene and Zoonoses, Faculty of Veterinary Medicine, Mansoura University, Mansoura 35516, Egypt.
Avian and Rabbit Medicine Department, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt.
Poult Sci. 2024 Feb;103(2):103320. doi: 10.1016/j.psj.2023.103320. Epub 2023 Nov 25.
Salmonella is a significant foodborne pathogen that has a significant impact on public health, and different strains of multidrug resistance (MDR) have been identified in this genus. This study used a combination of phenotypic and genotypic approaches to identify distinct Salmonella species collected from poultry broiler and layer farms, and antibiotic sensitivity testing was performed on these species. A total of 56 Salmonella isolates were serotyped, and phenotypic antibiotic resistance was determined for each strain. The enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) method was also used to provide a genotypic description, from which a dendrogram was constructed and the most likely phylogenetic relationships were applied. Salmonella isolates were detected in 20 (17%) out of 117 samples collected from small-scale broiler flocks. Salmonella isolates were classified as MDR strains after showing tolerance to 4 antibiotics, but no resistance to cloxacillin, streptomycin, vancomycin, or netilmicin was observed. From a genotypic perspective, these strains lack dfrD, parC, and blasfo-1 resistant genes, while harboring blactx-M, blaDHA-L, qnrA, qnrB, qnrS, gyrA, ermA, ermB, ermC, ermTR, mefA, msrA, tet A, tet B, tet L, tet M resistance genes. The genotyping results obtained with ERIC-PCR allowed isolates to be classified based on the source of recovery. It was determined that Salmonella strains displayed MDR, and many genes associated with them. Additionally, the ERIC-PCR procedure aided in the generation of clusters with biological significance. Extensive research on Salmonella serotypes is warranted, along with the implementation of long-term surveillance programs to monitor MDR Salmonella serotypes in avian-derived foods.
沙门氏菌是一种重要的食源性致病菌，对公共卫生有重大影响，该属已鉴定出不同的多药耐药（MDR）菌株。本研究采用表型和基因型相结合的方法，鉴定从家禽肉鸡和蛋鸡养殖场采集的不同沙门氏菌种，并对这些种进行抗生素敏感性测试。共对 56 株沙门氏菌进行了血清型鉴定，并对每种菌株进行了表型抗生素耐药性测定。还使用肠杆菌重复基因间共识聚合酶链反应（ERIC-PCR）方法提供基因型描述，构建了系统发育树，并应用最可能的系统发育关系。从 117 个小型肉鸡群中采集的样本中，检测到 20（17%）个样本中存在沙门氏菌。沙门氏菌分离株对 4 种抗生素表现出耐药性，被归类为多药耐药株，但对氯唑西林、链霉素、万古霉素和奈替米星无耐药性。从基因型角度来看，这些菌株缺乏 dfrD、parC 和 blasfo-1 耐药基因，但携带 blactx-M、blaDHA-L、qnrA、qnrB、qnrS、gyrA、ermA、ermB、ermC、ermTR、mefA、msrA、tet A、tet B、tet L、tet M 耐药基因。ERIC-PCR 获得的基因分型结果允许根据回收来源对分离株进行分类。确定沙门氏菌株表现出多药耐药性，并且存在许多与之相关的基因。此外，ERIC-PCR 程序有助于生成具有生物学意义的聚类。需要对沙门氏菌血清型进行广泛研究，并实施长期监测计划，以监测禽源性食品中的多药耐药沙门氏菌血清型。
