Relationship between genital carriage and udder infection with Mycoplasma bovigenitalium in dairy farms

[Abstract] We isolated Mycoplasma bovigenitalium(M.bg) from the vagina and the farm environment of the postpartum primiparous cows in two dairy farms where M.bg was previously detected in milk, and these strains were genotypically analyzed using pulsed-field gel electrophoresis. M.bg of various genotypes were detected at high rates in the vagina and the environment. Some of the M.bg detected from the vagina and environment had the same genotype as detected from previous positive milk. In these farms, there were cows carrying M.bg in their genital organs, and it was possible that M.bg could enter the udder through the environment from the lochia of postpartum cows. Our results indicate that it is important to manage postpartum cows to prevent udder infection with M.bg.