Producers sometimes call about a stillborn calf, or a calf that has been aborted, and ask what is wrong and what do I do? I usually tell them it is a good idea to take it to the Diagnostic Lab, for an autopsy, to determine the cause. One of the most common causes is Lepto.
Leptospirosis, or “Lepto”, is a bacterial disease affecting cattle, which is carried in the urine of wild animals, especially rodents. Leptospirosis may be transmitted to cattle by many infected species—rats and other rodents, raccoons, skunks, foxes, opossums, dogs and possibly even deer. The disease can also be transmitted to people, and swimming in waters frequented by infected animals should be avoided. The bacteria can survive in water for up to 150 days and so can show up even in a closed herd where no outside animals are brought in.
Losses from Lepto are usually realized from abortions and stillbirths. Lepto causes abortions late in pregnancy and can be diagnosed from blood or urine samples, or through autopsy of the fetus. Since there are multiple abortion causing diseases of cattle, producers should attempt to determine the exact cause of death whenever an abortion occurs. Most all of these diseases can be brought under control fairly easily.
Producers can reduce the risk of Lepto by fencing cattle out of ponds and streams and piping water to water troughs or drinkers. Because infected animals shed the bacteria in their urine, preventing them from contaminating water sources such as ponds or streams goes a long way in reducing the spread of Lepto.
There also a number of good vaccines available which give adequate protection with only an annual booster after the initial 2 injections. These vaccines provide good protection against disease with the possible exception of serovar Hardjo. Research indicates that some five-way leptospirosis vaccines do not provide good protection from serovar Hardjo infection. New vaccines have been introduced to address this issue. If you have had problems or outbreaks of abortions from Lepto, vaccinating every 6 months can help further reduce risk of abortions.
Abortions in cattle from Lepto can be devastating to the cattle producer, but by understanding this disease, and taking these steps to lessen the risk to your herd, you can hopefully avoid any complications from Leptospirosis.
