Molecular detection of antibiotic-resistant Campylobacter spp. among broiler and layer chickens in Egypt: An outlook from a One Health concept.

Campylobacter is a zoonotic pathogen that poses a public health concern, with poultry acting as the main reservoir of human infection. This study aimed to look into the prevalence and risk factors associated with antibiotic-resistant Campylobacter spp. found in chicken cloacal swabs using direct polymerase chain reaction (PCR) detection, highlighting their importance for public health. In this study, 108 pooled chicken cloacal swabs from 270 broilers and 270 layers were included. Following DNA extraction, the extracted DNA was examined for the presence of Campylobacter 16S rRNA, along with the mapA gene in Campylobacter jejuni (C. jejuni) and the ceuE gene in Campylobacter coli (C. coli). Next, the key antibiotic resistance genes (gyrA Thr-86-Ile mutation for C. jejuni, gyrA Thr-86-Ile mutation for C. coli, tetO, cmeB, and bla) were looked for in the pools that tested positive for Campylobacter. The prevalence rate of C. jejuni and C. coli was 12 % and 1.9 %, respectively, with 0.9 % carrying both species. TetO was the most common antibiotic resistance gene, found in 75 % of both broilers and layers, followed by bla, which was found in 50 % of broilers and 12.5 % of layers, while the gyrA Thr-86-Ile mutation and cmeB genes were found in broilers at rates of 37.5 % and 25 %, respectively. The phylogenetic analysis of the obtained Campylobacter 16S rRNA sequences harbouring two or more antibiotic resistance genes reveals a genetic relatedness to Campylobacter strains isolated from chickens, animals, and humans, highlighting their public health significance. In conclusion, direct PCR detection of antibiotic-resistant Campylobacter in chicken feces provides better insights into the prevalence of antibiotic-resistant Campylobacter spp. among chickens in Egypt.