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Animal Diseases

​The Illinois Department of Agriculture's Bureau of Animal Health and Welfare is responsible for detection and eradication of certain animal diseases. State veterinarians perform epidemiological investigations, develop plans to eradicate disease in infected herds, and monitor and test animals. Animal health and welfare investigators assist state field veterinarians with livestock testing, test poultry for disease and ensure livestock owners comply with testing requirements. These officials also inspect livestock markets for proper sanitation, monitor livestock identification and ensure animals are transported properly.

Reportable Diseases - Diseases on this list are required to be reported to the Bureau of Animal Health and Welfare. The reporting requirement can be satisfied by contacting the Bureau at 217/782-4944.

What does the Agriculture Department do to help eradicate animal disease in Illinois?

The following paragraphs summarize how the department works toward eradication of animal diseases. 

**Our website is currently under revision.  Please visit the Livestock and Poultry Health section and click on the animal species of interest for other disease information. 

Bovine Spongiform Encephalopathy (BSE)

Bovine Spongiform Encephalopathy (BSE) is known as "mad cow disease," is a slow, progressive, fatal disease of the nervous system of cattle. It typically occurs in cattle 5 years of age of older. BSE has been found in cattle native to the USA and Canada. Scientific evidence suggests BSE is associated with a rare human disease called variant Creutzfeldt-Jakob Disease (vCJD).

Diagnosis of BSE is difficult because there are no live animal tests. Preventing transmission of the BSE agent is the only safeguard available because there are no treatments and no vaccines available.


Illinois has maintained bovine brucellosis-free status since 1992 and swine brucellosis-free status since 1984, enabling the state to repeal some industry testing requirements. Brucellosis is a contagious bacterial disease that may cause pregnant females to abort and animals of both sexes to become infertile. Brucellosis does not contaminate the meat from infected animals but may reduce milk yields in infected dairy cows.

As a surveillance measure, the Department of Agriculture tests for brucellosis at slaughter facilities. Cattle sold through auction markets may also be subject to test to ensure they are free of this disease before being introduced into a new herd.


Illinois achieved bovine tuberculosis-free status in 1986 after 67 years of working toward eradication.

As a preventive measure, cattle entering Illinois for exhibition from states with a high incidence of tuberculosis must test negative for the disease. To prevent transmission of tuberculosis from captive deer and elk to livestock, the Department requires deer and elk transported into the state test negative for tuberculosis prior to entry.


Johne's disease, or paratuberculosis, is a chronic disease in cattle, bison, cervids (deer and elk), sheep and goats, marked by chronic, intermittent diarrhea that does not respond to treatment.

Infection occurs with the ingestion of the Johne's bacteria through feed or water contaminated with feces, or from bacteria on the teat or udder of the dam. Trans-placenta infection is also possible. Additionally, the bacteria can also be passed through colostrum or milk.

There is no cure for Johne's disease.

Voluntary Paratuberculosis Certification and Risk Management Programs are available for producers. These programs enable producers to certify that their herds or flocks are monitored for Johne's disease.

Foot and Mouth Disease

Foot and mouth disease is a highly communicable viral disease of cattle, swine, sheep, deer, goats, and other cloven-hooved ruminants.

Contact Information

For more information about these and other animal health programs administered by the Department, contact:

Illinois Department of Agriculture
Bureau of Animal Health and Welfare
P.O. Box 19281
State Fairgrounds
Springfield, IL 62794-9281

TDD: 866-​287-2999
FAX: 217-558-6033