Risk Factors for Pathogen Occurrence, Antimicrobial Use and Resistance in Veal Farms

Presentation Description / Summary: Risk factors associated with the presence of viral and bacterial pathogens associated with Bovine Respiratory Disease (BRD), with increased antimicrobial use, as well as with the presence of resistant bacteria (Pasteurellaceae isolated from nasopharyngeal swabs, E. coli from rectal swabs) have been investigated in different types of veal fattening operations in Switzerland. The results of these studies confirm that numerous management practices related to calf purchase, transport, biosafety measures upon arrival in the fattening farm, as well as housing and handling of the calves during the fattening period are associated with the prevalence of BRD pathogens, treatment incidence and antimicrobial resistance in veal farms. These results further show that levels of bacterial resistance are also associated with the application way of antimicrobial drugs, as group treatments were associated with higher and individual treatments with lower resistance rates. FInally, it was confirmed that improvement in the management of veal calf farms not only allowed for decreased antimicrobial use, but also resulted in decreased levels of antimicrobial resistance at the end of the fattening period. This is highly relevant in a one-health perspective, as less resistant, especially less multiresistant bacteria in the calves' fecal flora means a reduced risk of human exposure to resistance determinants from animals through the food chain. The close relationships between antimicrobial treatments and resistance underlines the veterinarians' responsability in reducing health hazards resulting from resistant bacteria for humans and animals. New pathways of optimized management must be implemented to reduce the need for antimicobials in veal farms.