Last week I spoke with a local producer who had lost 3 heifers to suspected blackleg. Blackleg is endemic to the area, but very preventable either through vaccination or early treatment with antibiotics.
Blackleg is caused by the bacteria Clostridium chauvoei, which can form spores under adverse conditions and lay in the soil for a long period of time. According to veterinarians, times of wet weather followed by times of dry conditions, like those experienced this spring, seem to cause increased concentration of the spores in pocket on the ground, which often result in more than average cases of the disease being reported.
The Merck Veterinary Manual provides a detailed description of the disease. Calves should be vaccinated against this disease between 2 to 6 months of age, with 2 doses of vaccine given 2 weeks apart. Re-vaccinate replacements at 1 year of age and then every 5 years thereafter, or as directed by your veterinarian.
If you suspect a case of black leg in your cattle, re-vaccinate the herd and consult with a vet about giving prophylactic antibiotic treatments to help prevent new cases.
