In a case‐control study of risk factors forSalmonella dublinon 126 dairy farms the following variables were significantly associated with infection. Standardized herd size and water surface area showed a positive association. Contact with cows from other herds during exchange was, unexpectedly, preventive forS. dublininfection. Purchase of cows from other herds was a risk factor. More infections occurred when the feed consisted of grass only compared to grass supplemented with maize or silage.S. dublininfection was highly associated with a liver fluke infection.