Ask the Vet

By Dr. Ken McMillan, Contributing Columnist

READER QUESTION:

Years ago, we vaccinated our calves for brucellosis, but after our state was declared free, we stopped. I read that there are still occasional cases found out West. Is there any reason to start back?

DR. KEN MCMILLAN'S ANSWER:

One of the great success stories of the USDA is the eradication of both brucellosis and tuberculosis from most of the United States. Both diseases were brought under control through an aggressive testing program and, with brucellosis, calfhood vaccination.

Today, there are only occasional spillover cases of brucellosis in cattle around Yellowstone National Park. Wild bison and elk are thought to be the last remaining reservoir of this disease in the country.

Brucellosis is a serious disease of cattle and other livestock that can lead to abortion and infertility. Additionally, the disease is zoonotic, with veterinarians and farmers who have acquired the disease, causing life-altering effects.

I would suggest talking with your veterinarian to see if vaccination makes sense. For all vaccines, we recommend doing a risk assessment. For example, in Alabama, we do not routinely recommend vaccination of Lyme disease in dogs because it's uncommon in our area. If I practiced in areas where the disease is "endemic," a fancy technical word that means common in a particular area, I would recommend it. For most of our producers, we do not recommend brucellosis vaccination. We have a couple of purebred producers who market cattle out West who chose to vaccinate. This is more of a marketing decision rather than for the prevention of disease in their herds.

The vaccine must be given by a veterinarian accredited by the USDA. A special tattoo with the letter R, the official USDA "shield," and the last digit of the year of vaccination, is placed in the center rib of the right ear. An orange electronic ID button is also placed in the right ear. An official form is completed and submitted to the state veterinarian's office.

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Editor's Note: Please contact your veterinarian with questions about the health of your herd or other animals. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice but is purely for informational purposes. Email Dr. Ken McMillan at vet@dtn.com.

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