One of the biggest global problem is the increasing amount of antimicrobial resistances (AMR) leading to challenges in treatment of bacterial infections. The AMR problem is not limited to human medicine, but is also present in livestock. For the monitoring of ESBL-E. coli and MRSA in two different poultry farms we are conducting a longitudinal study that started December 2023. These two pathogens are characterized by a high zoonotic potential. With this study we want to gain insights into the on-farm dynamics of ESBL E. coli and MRSA in poultry farms. To achieve this, animals are sampled weekly (broiler farm) and every two weeks (laying hen farm) and in addition farm related data are collected monthly. Fecal samples are then examined for the presence of ESBL E. coli and MRSA using chromogenic media. Obtained isolates are subjected to antibiotic susceptibility testing using a VITEK 2 apparatus. Additionally, the isolates will be whole genome sequenced and analyzed.

So far, no MRSA were detected. ESBL-E. coli was present on the broiler farm, only sporadically at first, two weeks after stabling in all samples. In the laying hen farm, ESBL-E. coli was only detected sporadically from the 62nd week of life (two months after start of sampling), both in floor-and free-range farming. Additionally, to the investigation of the further samples, we evaluate the information regarding potential risk factors for the prevalence. The Study will take a total of two years.