Bovine Tuberculosis Testing Requirements in Tennessee: What Cattle Owners Must Know

Bovine tuberculosis has been nearly wiped out of American livestock herds, yet the disease still shows up often enough that Tennessee cattle owners cannot skip testing altogether. Bovine tuberculosis testing requirements in Tennessee apply mainly at the point of interstate movement, herd investigations, and specific classes of cattle, bison, and captive cervids rather than as routine annual testing for every farm.

If you raise, sell, or transport cattle in Tennessee, you need to know which animals are covered, which tests state and federal officials accept, and what happens if a test comes back suspect. This guide walks through the classification system behind Tennessee’s program, the approved testing methods, and the enforcement rules that keep the state’s cattle industry protected from a disease that still circulates in pockets of the country.

What Is Bovine Tuberculosis and Why It Is Regulated in Tennessee

Bovine tuberculosis is caused by Mycobacterium bovis, a bacterium closely related to the organism that causes human tuberculosis. Bovine tuberculosis (TB) is a contagious, infectious, communicable disease of animals and humans caused by Mycobacterium bovis, and it is commonly a chronic, debilitating disease but occasionally may assume an acute, rapidly progressive course. TB is a widespread zoonosis of global magnitude and affects nearly all species of vertebrates, and disease is spread by direct contact, inhalation of droplets expelled from infected lungs, and ingestion of contaminated feed or milk.

The reason regulators still take the disease seriously despite its rarity comes down to both economics and public health. The prevalence of tuberculosis in cattle, bison, and captive cervids is extremely low in the United States, with an estimated prevalence of 7 per 1 million cattle screened. That low number is the result of a century-long federal-state partnership. In 1917, the U.S. Bureau of Animal Industry began the National Tuberculosis Eradication Program due to human and livestock concerns regarding bovine tuberculosis. Tennessee participates in this cooperative program alongside every other state, which is why testing rules here mirror federal standards even though day-to-day enforcement runs through the Tennessee Department of Agriculture’s animal health division. Bovine TB is not the only mycobacterial disease producers confuse with one another; poultry keepers sometimes ask about avian tuberculosis, which is caused by a different bacterium and has no connection to the cattle program described here.

Pro Tip: Because infected cattle are almost always asymptomatic, do not assume a healthy-looking animal is TB-free. Testing and slaughter surveillance remain the only reliable detection tools.

Tennessee’s TB Classification Status and Risk Zones

The national program sorts states and zones into tiers based on how much tuberculosis has turned up in recent years. An accreditation preparatory State or zone is one that has the authority to enforce and complies with the provisions of the Uniform Methods and Rules—Bovine Tuberculosis Eradication and in which tuberculosis is prevalent in less than 0.5 percent of the total number of herds of cattle and bison in the State or zone. A modified accredited State or zone is one in which tuberculosis has been prevalent in less than 0.1 percent of herds for the most recent year, while a modified accredited advanced State or zone requires prevalence below 0.01 percent for each of the most recent two years. The top tier, accredited-free, requires the longest clean track record. Tennessee currently appears on the federal list of modified accredited states for the classification tied to captive cervid herds, alongside most other states in the country. This classification is distinct from the cattle and bison program: Tennessee’s import rules exempt cattle arriving from other TB-free states from additional testing, which reflects the state’s own strong standing under the cattle and bison side of the program. The state’s animal import chart lists tuberculosis testing requirements with the note that no testing is required from TB-free states.

Status is not permanent. Accredited-free State or zone status must be renewed annually, and to qualify for renewal a State must submit an annual report to APHIS certifying compliance with the Uniform Methods and Rules. If two or more affected herds are detected in an accredited-free State or zone within a 48-month period, the State or zone will be removed from the list of accredited-free States or zones and reclassified as modified accredited advanced. That downgrade risk is why a single positive herd triggers an intense, time-limited response rather than a routine cleanup. Wildlife reservoirs add another layer of risk that state veterinarians track closely, since deer and other cervids can carry and spread the bacterium. If you hunt or manage land where white-tailed deer populations overlap with cattle pasture, understanding TB risk zones matters just as much as understanding Tennessee’s hunting license requirements, since state wildlife surveillance data feeds directly into the same eradication reports used to set herd testing priorities.

Who Must Test and Which Animals Are Covered in Tennessee

Testing obligations in Tennessee fall on cattle, bison, and captive cervids, with age thresholds that shift depending on the state or zone’s classification tier. Testing of herds for accreditation or reaccreditation covers, in accredited-free States or zones, all cattle or bison 24 months of age and older; in modified accredited advanced States or zones, all cattle or bison 18 months of age and older; in modified accredited States or zones, all cattle or bison 12 months of age and older; and in accreditation preparatory States or zones, all cattle and bison regardless of age.

Classification Tier	Test-Eligible Cattle/Bison Age	Herd Test Frequency
Accredited-Free	24 months and older	Biennial
Modified Accredited Advanced	18 months and older	Biennial
Modified Accredited	12 months and older	Annual
Accreditation Preparatory	All ages	Annual

Accredited herd status is maintained through annual herd testing in Accreditation Preparatory and Modified Accredited States or zones, and through biennial herd testing in Modified Accredited Advanced and Accredited-free States or zones during a period of 3 months prior to the anniversary date to 3 months following the anniversary date. Goats have a lighter compliance history in this program. The program was mandatory for cattle and voluntary for goats when it began.

Exotic and zoo species fall outside the standard framework. TB testing and test result interpretation for many exotic species, such as some zoo animals, are not yet developed or reliable, so for interstate movement of these animals producers should contact the State animal health official in the State of destination. Only trained professionals can legally conduct the test. Veterinarians are legally responsible for properly conducting and evaluating the results of tuberculin tests, so an accredited veterinarian must perform the test personally rather than delegate the responsibility to a technician. The same standard applies to livestock movement paperwork you may already be familiar with if you have worked through Tennessee’s EIA/Coggins testing requirements for horses, since both programs rely on accredited veterinarians to certify results before animals cross state lines.

Approved TB Testing Methods in Tennessee

Tennessee follows the federal testing hierarchy rather than a separate state-specific test menu. The screening test used on virtually all cattle is the caudal fold test (CFT), an intradermal tuberculin injection read by hand. If an animal is exposed to the antigens present in bovine TB, a tuberculin injection results in a delayed hypersensitivity reaction manifested by swelling and induration at the injection site, with a positive response usually beginning within 8 to 12 hours and peaking about 72 hours after injection.

Veterinarians record results using standardized codes. Using VS Form 6–22, the veterinarian enters “N” for negative when no change is observed in the tissue at the injection site, and “S” for suspect when any increase in caudal fold thickness, size, or sensitivity is observed or palpated. Test observation without palpation is unacceptable.

A suspect result does not confirm infection on its own. These “false-positive” responses may occur in 1 to 5% of tested cattle, so follow-up confirmatory testing is required before any animal is classified as a reactor. Confirmatory options include the comparative cervical test (CCT) and the gamma interferon (BOVIGAM) blood assay. Follow-up CCT testing must be performed within 10 days of the initial caudal-fold injection in cattle and bison, or the herd owner must wait 60 days after the injection of the CFT before a follow-up CCT can be administered; if the gamma interferon test is used instead, the blood must be drawn within 30 days of the CFT injection date, and the gamma interferon test is not approved for use in bison or captive cervidae.

Important Note: Only federally trained regulatory veterinarians may conduct confirmatory follow-up testing once a caudal fold test comes back suspect. Producers cannot rely on a general practice veterinarian for this step alone.

Interstate and Intrastate Movement Testing Requirements in Tennessee

Most Tennessee producers encounter TB testing rules when animals cross state lines. The Tennessee Department of Agriculture’s import chart spells out exactly which classes of cattle need testing before entry. The chart lists tuberculosis testing as required except for animals coming from TB-free states. Intact bulls face an additional layer of scrutiny for a separate reproductive disease. All out-of-state intact male cattle 18 months of age and over must have a Certificate of Veterinary Inspection, official ID, and a trichomoniasis test completed within 30 days of entry, with the testing information listed on the CVI.

Bison and buffalo generally follow the same rulebook as cattle. Buffalo and bison must meet the same import requirements as cattle, with the exception of trichomoniasis testing for bulls. Captive cervids face a stricter, dual-disease standard because of their role as a TB reservoir species. A cervid entering Tennessee needs one USDA-approved tuberculosis and brucellosis test within 90 days prior to import along with proof the animal originated from a herd that tested negative on a whole-herd tuberculosis test within the prior 12 months, or two USDA-approved tuberculosis and brucellosis tests conducted at least 90 days apart with the second completed within 90 days of import.

Paperwork rules matter just as much as the test itself. Official identification means NUES “brite” tags, Bangs (orange) tags, or “840” tags, and metal tags are only official if applied before November 5, 2024. Anyone hauling cattle into or through the state should also review Tennessee’s livestock trailer requirements, since transport documentation and the certificate of veterinary inspection travel together during any inspection stop. A valid CVI generally has a short shelf life for movement purposes, similar to the paperwork window used for rabies vaccination compliance in other animal categories the state regulates.

What Happens When a Suspect or Positive Result Occurs in Tennessee

A suspect caudal fold reading sets off an immediate reporting chain. All accredited veterinarians must immediately report every suspected or diagnosed bovine TB case promptly to both the Assistant District Director and the State Animal Health Official. From there, the animal moves into a formal confirmatory pathway rather than an automatic culling decision. The caudal-fold test is used as a presumptive diagnostic procedure, and animals classified as suspect must be evaluated further by the comparative cervical test, gamma interferon test, or sent directly to slaughter under permit.

Once a reactor is confirmed, the case is escalated out of routine veterinary hands. If the CCT or gamma interferon test indicates that the animal is a reactor, all further herd testing is conducted by Federal or State regulatory veterinarians. Investigators do not stop at the affected farm. All livestock herds within a 10-mile radius will be tested within 6 months of any diagnosis of bovine tuberculosis. That radius requirement is one reason a single positive result in Tennessee can trigger testing obligations for neighboring operations that had no direct contact with the infected animal.

Quarantine and Herd Depopulation Rules in Tennessee

Once tuberculosis is confirmed in a herd, Tennessee’s options track the same two federal pathways used nationwide. When health officials find tuberculosis in a herd, it is managed by either depopulating the herd or by testing and removing reactor animals. There is no third option that leaves an infected animal in production. Tuberculosis is not treated in livestock.

Speed matters for the state’s broader classification. If an affected herd is detected in a State or zone classified as accredited-free, and the herd is depopulated and an epidemiologic investigation is completed within 90 days of detection with no evidence of spread, the State or zone may retain its accredited-free status. Miss that window, or accumulate a second affected herd within four years, and the entire state’s classification drops, dragging every other producer’s export and movement paperwork down with it. Restocking a depopulated premises comes with its own testing schedule. The tests on a newly assembled herd must be conducted at 9- to 15-month intervals, and if any livestock other than cattle or bison are included in a newly assembled herd on a premises where a tuberculous herd has been depopulated, the State or zone must apply the same herd test requirements to those other livestock as to cattle and bison.

Penalties for Non-Compliance in Tennessee

Tennessee’s authority to enforce TB testing rests on the same legal foundation every accredited state must maintain under the national program. Regulatory officials must have the legal authority to inspect live animals and records, apply diagnostic tests for TB, inspect carcasses at slaughter, control animal movement into, within, and out of the region, establish quarantines, control the disposition of infected animals and affected herds, and enforce TB program requirements and penalize noncompliance. That legal framework is what gives the State Animal Health Official standing to hold, quarantine, or deny movement certificates for animals that lack required testing or documentation.

Practically, non-compliance most often shows up as a rejected or held shipment: an intact bull without a trichomoniasis test, a cervid without the required whole-herd TB history, or a CVI issued outside the valid window will stop movement at the point of inspection rather than after the fact. Producers who repeatedly move untested or improperly documented animals risk quarantine orders on their own premises in addition to any fines assessed under Tennessee’s animal health statutes.

Important Note: Specific civil and criminal penalty amounts for TB testing violations are set at the state level and can change. Confirm current fine schedules and enforcement procedures directly with the Tennessee Department of Agriculture’s State Veterinarian’s office before assuming a specific dollar figure applies to your situation.

Staying ahead of these rules is far simpler than dealing with a quarantine notice. Keep certificates of veterinary inspection current, confirm official identification on every animal before it leaves the farm, and work with an accredited veterinarian who understands both the cattle program and any captive cervid rules that might apply to your operation. Whether you are moving other regulated animals or hauling cattle across county lines, the same principle holds: Tennessee’s animal health paperwork exists to catch problems before they become outbreaks, and a little preparation at the farm gate saves considerable trouble at the state line.