Prevalence of antibodies to Leptospira hardjo in bulk tank milk from unvaccinated dairy herds in the south-west region of Poland.

Bulk tank milk samples were collected from 309 randomly selected dairy cattle herds from the south-western region of Poland in 2010-2011. Samples were tested for antibodies against Leptospira hardjo using DAS-ELISA. Herd level seroprevalence of antibodies against this serovar was low (3.