Brucellosis Testing and Regulations

Brucellosis is a reportable cattle disease that causes abortions and can infect people. Ranchers do not manage it alone, and rules and testing requirements are set by state and federal officials.

Key points

Brucellosis causes abortions and can infect people.
State and federal officials set testing and movement rules.
Rules differ by state, so check with your state veterinarian.
Wear gloves and wash up around birth material and abortions.
Call your vet, the state veterinarian, or USDA APHIS if you suspect it.

What brucellosis is

Brucellosis is a bacterial disease of cattle that causes late-term abortions, weak calves, retained afterbirth, and lower fertility. Infected cows shed large numbers of bacteria in birth fluids, aborted fetuses, and sometimes milk.

In the United States, long-running state and federal programs have removed the disease from most cattle herds, but it persists in wildlife in certain regions. Because of that, awareness still matters on ranches near those areas and for any rancher who buys or sells cattle.

Because wildlife can serve as a source in some areas, fencing, feed storage, and separating cattle from wildlife contact points can be part of a plan your vet helps you build.

Why it is regulated

The disease is regulated because it harms herds, affects trade, and can infect people. State animal health officials and USDA APHIS run the programs, and they decide what testing, vaccination, identification, and movement rules apply.

These rules differ from state to state and can change. This article does not tell you what your state requires. Check with your state veterinarian, your state department of agriculture, or USDA APHIS.

Risk to people

Brucellosis can spread to people through contact with infected birth fluids, aborted fetuses, and in some cases unpasteurized dairy products. People who work with cattle at calving face the most exposure. Illness in people can be long and hard to diagnose.

Wear gloves when handling birth material, wash well afterward, and tell your doctor that you work with livestock if you become ill. CDC provides guidance for people working with animals.

Wear gloves during calving and abortions
Wash hands and gear afterward
Keep children and pets away from birth material
Avoid unpasteurized milk products
Tell your doctor about livestock contact

Testing and identification, in general terms

Testing is done by or under the direction of accredited veterinarians and approved labs. Programs may require tests for certain cattle moving across state lines, for animals sold in some settings, or after an abortion investigation. Official identification helps officials trace animals.

Which animals need testing, which ages, and which records you must keep depend on where you live. Do not rely on a neighbor's advice. Ask your vet to explain the requirements for your cattle.

Official ear tags or other approved identification may be required for certain cattle. Do not remove or swap tags, since the number is how officials trace an animal back to its herd.

When a cow aborts

Do not assume an abortion is routine. Call your veterinarian, and in areas of concern ask about testing, since an abortion can be an early sign of a reportable disease. Wear gloves, keep other animals and dogs from the fetus and afterbirth, and do not dispose of material until you have guidance.

Separate the cow from the herd and record the details. Never handle suspect carcasses yourself without guidance from your vet or state officials.

Ask your vet in advance what samples to save and how to store them, so you are not guessing in the middle of a hard day at calving.

Buying, selling, and records

Ask sellers about herd health and the testing and vaccination status of any cattle you buy, and ask your vet what your state requires for imports. Keep health papers, test records, and identification for as long as officials and your vet advise.

If you ranch near wildlife areas known for the disease, ask your vet about herd protection and how to reduce contact between cattle and wildlife.

Common mistakes

Treating abortions as normal, handling birth material without gloves, moving cattle without checking the rules, and failing to keep records are the main errors. Another is waiting to call. Early reporting protects your herd, your neighbors, and your family. If you suspect a reportable disease, call your vet, the state veterinarian, or USDA APHIS right away.

Talk to your family and hired help ahead of time about what to do and who to call, since the person who finds an abortion first is not always the owner.

When to get help: Call your veterinarian after any abortion, and contact the state veterinarian or USDA APHIS immediately if brucellosis is suspected. Do not handle suspect carcasses yourself, and ask your vet what testing and papers your state requires.

Sources and further reading

Organization homepages are linked so you can search them for current guidance on this topic.

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