Whole-genome sequencing ofserovars isolated from diarrheic and non-diarrheic foals.

Abstract

spp. are important pathogens of foals, causing clinical enterocolitis and sepsis. We characterized the resistance, virulence, and stress response genes inisolates from foals with or without diarrhea.isolates (&#x2009;=&#x2009;23) recovered from fecal samples of 16 diarrheic and 7 non-diarrheic <1-y-old foals were subjected to whole-genome sequencing. The most common serovars detected in diarrheic foals weresubsp.serovars Infantis and Minnesota. Multidrug resistance was observed in 9 of 23 isolates, with 8 of the 9 from diarrheic foals. All of the isolates contained at least 2 resistance genes, with most of the genes related to the multidrug efflux pump complex. Among the 9 isolates shown to be resistant to &#x3b2;-lactam antimicrobials, at least one antimicrobial resistance gene (ARG) related to the inactivation of these antimicrobials was observed (,,). Among the 7 isolates resistant to the quinolone class, 3 contained ARGs (,). The occurrence of multidrug-resistant isolates, particularly among foals with diarrhea, and the zoonotic potential ofspecies, highlight the importance of implementing biosecurity measures on the studied farms.