In this study, herds with a high frequency of animals with antibodies against Salmonella are compared to herds with a low frequency of such animals in order to evaluate the relevance of presumed risk factors and/or to identify so far unknown risk factors. A standardised, validated questionnaire was used to document a multitude of characteristics from each farm. Faeces and environmental samples were also gathered with the intention of corroborating the salmonella-specific relevance of the potential risk factors as queried by the survey. These samples were analyzed by means of Real-Time PCR.