Prevalence of multidrug resistance in Escherichia coli in the immediate calves' environment in Swiss dairy farms

In dairy farms, calves are the animal group that carries the fecal flora with the highest prevalence of antimicrobial resistance (AMR). Calves' age and antimicrobial exposure are major factors affecting AMR prevalence. The calves' housing environment is suspected to be a reservoir of resistant bacteria, acting as a source of colonization of the calves' gut and maintenance of AMR in farms. Aims To describe the prevalence of AMR and multidrug resistance (MDR) in Escherichia coli isolated from preweaned calves' housing environment in Swiss dairy farms To explore factors associated with AMR and MD