The semen can contain bacteria . By contact with the bacteria. Colostrum from cows with Brucellosis can give the disease to calves from cows which do not have Brucellosis. This means the cow has become a carrier that can infect the rest of the herd. Bacteria are especially found in the placenta, aborted foetuses, uterine fluid and discharge from the vagina as well as milk from infected cows.
Colostrum can transmit the disease to calves of uninfected cows.
Semen used from infected bulls can also transmit the disease to cows by A.I. or, in rare cases, by natural breeding. Bacteria spread by infected cows can survive for weeks outside the body, and the possibility of spreading disease through con-taminated tools, people or other animals is large. The incubation period, i.e. the period from exposure to the infective agent until signs of disease, is very different from case to case, from about 1-2 weeks until several months. 21 Bacteria live for some time outside the body . Vehicles, equipment and you can easily carry the bacteria from one animal to another.