Bovine Tuberculosis Testing Requirements in Mississippi: Rules Every Cattle Owner Must Follow

Bovine tuberculosis testing requirements in Mississippi catch a lot of cattle owners off guard, especially when they try to haul animals across state lines without a current negative test on file. Mississippi sits in the federal “modified accredited” category, which puts extra testing obligations on producers that free states simply don’t face. Whether you’re buying a bull at auction, hauling heifers to a show, or bringing exotic bovidae onto your property, the rules below determine whether that animal legally sets foot in the state.

This breakdown covers what the disease actually does, how Mississippi’s status shapes day-to-day testing, who has to test which animals, and what happens if a test comes back suspect or positive. It also covers the quarantine and penalty framework that backs up the entire system, so you know exactly what’s at stake if paperwork or testing gets skipped.

What Is Bovine Tuberculosis and Why It Is Regulated in Mississippi

Tuberculosis is a contagious disease of both animals and humans caused by three specific types of bacteria in the Mycobacterium group: M. bovis, M. avium, and M. tuberculosis, and bovine TB, caused by Mycobacterium bovis, can be transmitted from livestock to humans and other animals. The disease spreads through inhaled droplets, contaminated feed, or unpasteurized milk, which is exactly why regulators treat it as a public health issue and not just a livestock production problem.

In 1917, the U.S. Bureau of Animal Industry began the National Tuberculosis Eradication Program due to human and livestock concerns regarding bovine tuberculosis, starting out strictly for cattle before eventually including bison and farmed cervids. APHIS and state animal health agencies still collaborate with producers to run that program, which has nearly eradicated tuberculosis from the nation’s livestock population since its 1917 inception. Even so, the disease hasn’t been fully eliminated, which is why Mississippi still enforces testing rather than treating TB as a closed chapter.

Infected cattle are typically asymptomatic, and detection usually occurs during live animal skin testing or, more commonly, at slaughter through national slaughter surveillance, since clinical signs only appear once the disease has advanced to affect multiple organ systems, which is rare. That’s the core reason testing exists at all: without it, an infected animal can move through markets and pastures for years without anyone noticing. For background on how bovine TB compares to other livestock diseases regulators track, see this overview of common bovine diseases.

Pro Tip: Even if your herd has never had a TB scare, keep every past test chart on file. Buyers, sale barns, and inspectors routinely ask for testing history when cattle change hands or cross state lines.

Mississippi’s TB Classification Status and Risk Zones

Mississippi’s testing obligations trace directly back to its federal classification. Mississippi is listed among the modified accredited states under federal regulation, alongside states such as Alabama, Arkansas, Louisiana, and Tennessee. There are currently no modified accredited zones carved out within any state, meaning Mississippi’s classification applies uniformly statewide rather than to specific counties or regions.

That single designation matters because federal rules tie the age of cattle required for herd testing directly to a state’s status. Here’s how the tiers compare:

Classification	Cattle/Bison Required for Herd Testing	General Standing
Accredited-Free	24 months and older	Highest status; minimal ongoing testing burden
Modified Accredited Advanced	18 months and older	Above baseline; moderate testing burden
Modified Accredited (Mississippi’s tier)	12 months and older	Baseline compliance status
Accreditation Preparatory	All ages, regardless of age	Lowest status; heaviest testing burden

In accredited-free states or zones, testing for herd accreditation includes all cattle or bison 24 months of age and older; in modified accredited advanced states or zones, it covers animals 18 months and older; in modified accredited states or zones, it covers animals 12 months and older; and in accreditation preparatory states or zones, all cattle and bison regardless of age must be tested. Mississippi’s modified accredited standing means herds working toward accreditation or reaccreditation must test every animal 12 months or older, a wider net than states holding accredited-free status.

Accreditation itself isn’t a one-time event. To qualify for accredited herd status, a herd must pass at least two consecutive official tuberculosis tests conducted within an interval of 9 to 15 months with no evidence of bovine tuberculosis. That interval requirement is why producers pursuing herd accreditation need to plan testing dates well ahead of the anniversary window rather than scheduling tests reactively.

Important Note: A state’s modified accredited status is a general classification, not a sign of an active outbreak. It simply reflects the testing tier the state has qualified for under federal rules, and Mississippi has held this status for years without it indicating current disease presence.

Who Must Test and Which Animals Are Covered in Mississippi

Mississippi’s entry rules single out several categories of livestock, and the age and species of the animal determines exactly what’s required. All cattle over six months of age must be negative to an official tuberculosis test within 30 days prior to the date of shipment. All dairy cattle over six months of age must have a negative TB test prior to entering Mississippi.

Cattle aren’t the only animals covered. Exotic bovidae six months of age and over must be tested negative for brucellosis within 30 days prior to entry and negative to a tuberculosis test within 30 days prior to entry. Cervidae six months of age and over must also be tested negative for brucellosis within 30 days prior to entry and tested negative to tuberculosis with a cervical tuberculosis test within 30 days prior to entry. Camelidae used for milking must be tested negative to a brucellosis and an axillary tuberculosis test within 30 days prior to entry on all animals six months of age and older.

Not every animal has to test, though. Several exemptions apply under the state’s regulations:

• Cattle originating from an Accredited Tuberculosis Free Herd or beef cattle from an Accredited Free State
• Steers
• Cattle for immediate slaughter
• Cattle entering Mississippi on a show circuit, which qualify for a 60-day test instead of the standard 30-day window
• Steers and spayed heifers from any herd, along with official calfhood vaccinates of dairy breeds under 20 months and beef breed vaccinates under 24 months that are not parturient or post-parturient, from non-quarantined herds, which can enter without test restrictions

Owners moving cattle by trailer should also confirm their vehicle and paperwork meet state hauling standards, since a valid livestock trailer setup in Mississippi is required alongside the health documentation. TB testing isn’t the only mandatory animal health measure producers juggle either; Mississippi’s rabies vaccine requirements follow a similarly structured compliance model for a different zoonotic disease.

Approved TB Testing Methods in Mississippi

Only specific, federally recognized tests count as official for compliance purposes. The caudal-fold tuberculin test is an intradermal injection of 0.1 ml of USDA purified protein derivative tuberculin into either side of the caudal fold, with reading by visual observation and palpation 72 hours, plus or minus 6 hours, following injection. This is the standard field screening test used on cattle before interstate movement.

Only bovine purified protein derivative tuberculin licensed by USDA may be used for official testing. Test observation without palpation is unacceptable, and results are recorded on VS Form 6-22. A negative result is entered when no change in tissue is observed at the injection site, while a suspect result is entered when the examiner observes or palpates any increase in caudal fold thickness, size, or sensitivity at the injection site.

Animals that respond to the initial screening don’t automatically get labeled positive. 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. For captive cervids specifically, a blood tuberculosis test is a supplemental test used to establish the disease status of a herd.

Timing matters just as much as the test itself. Cattle, bison, goats, or captive cervids must not be subjected to a caudal-fold retest at intervals of less than 60 days. That waiting period exists because repeated injections too close together can desensitize the animal’s immune response and produce unreliable readings.

Pro Tip: Testing must be performed by an accredited veterinarian using USDA-licensed tuberculin. A test administered by an unaccredited practitioner, or with unapproved tuberculin, won’t satisfy Mississippi’s entry paperwork even if the result comes back negative.

Producers dealing with cervid or exotic species should also be aware that TB testing sits alongside other wildlife-disease rules in Mississippi, including the entry restrictions tied to chronic wasting disease covered in the state’s hunting license requirements. Owners curious about how bovine TB differs from tuberculosis strains in other species can compare it against avian tuberculosis, which behaves very differently in poultry and pet birds.

Interstate and Intrastate Movement Testing Requirements in Mississippi

Getting cattle into Mississippi legally involves more than a clean test result. All livestock entering Mississippi must be in compliance with the United States Department of Agriculture’s Animal Disease Traceability Rule. Official individual identification is required and must be tamper-proof, uniquely identifying the animal to the premises where it was tagged, with examples including official 840 RFID or visual tags.

Documentation requirements stack on top of testing. Livestock imports must meet Mississippi and federal interstate requirements, with a Certificate of Veterinary Inspection, permit, or waybill accompanying the shipment, and no animal affected with or recently exposed to an infectious, contagious, or communicable disease may be shipped into the state except when approved for interstate shipment by USDA APHIS Veterinary Services, or for immediate slaughter.

Permits add another layer for certain classes of animals. Permit requests go through the Mississippi State Veterinarian, all international imports require a prior entry permit, and securing that permit requires the consignor and consignee’s names and addresses along with the brucellosis and tuberculosis status of test-eligible cattle, swine, and exotics. Permits can be requested by calling 601-359-1170 at any time, though evenings and after-hours calls are answered by an answering machine.

Within the state, the same testing logic applies to movement between premises when quarantine status is involved. Test-eligible cattle may move directly from a farm of origin to a specifically approved stockyard in Mississippi for the required test, after which they may move to a farm in Mississippi, and a health certificate is required for test-negative cattle moving to a farm from an approved stockyard in another state, with no retest required in either instance. That provision lets producers consolidate testing at an approved facility rather than testing on every individual farm along the supply chain.

What Happens When a Suspect or Positive Result Occurs in Mississippi

A response on the initial screening test doesn’t automatically confirm disease, but it does trigger a defined process. A suspect is any bovine, bison, or goat that shows a response to the caudal-fold tuberculin test and is not classified a reactor, or is classified suspect by a comparative cervical test. A reactor is an animal diagnosed as infected with M. bovis based on a positive response to an official tuberculin test and classified a reactor by the testing veterinarian.

Reporting happens fast once a response shows up. If the test produces any type of response, the veterinarian must immediately notify APHIS Veterinary Services Area Offices and state animal health officials. 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, confirmatory testing takes over. With approval of the designated tuberculosis epidemiologist or regional epidemiologist, the comparative cervical test and/or bovine interferon gamma assay may be used to classify responders to the caudal-fold test. Because a positive screening result can stem from cross-reactions with harmless bacteria, this second round of testing is what separates a genuine reactor from a false alarm.

Common Mistake: Some owners assume a suspect classification means the animal is automatically condemned. In reality, suspects are held for confirmatory testing, not immediately destroyed, and many suspects clear on the follow-up comparative cervical test.

Quarantine and Herd Depopulation Rules in Mississippi

Mississippi law gives the Board of Animal Health broad quarantine authority once disease is confirmed. The state veterinarian’s inspectors and range riders are authorized to enter premises to inspect and disinfect livestock and premises and enforce quarantines. The Board is authorized to promulgate and enforce regulations necessary to control, eradicate, and prevent the spread of animal diseases, and it can establish and maintain quarantine lines by county, supervisor’s district, parcel of land, or premises.

Once a diagnosis is confirmed, surrounding herds face scrutiny too. All livestock herds within a 10-mile radius will be tested within 6 months of any diagnosis of bovine tuberculosis. That radius requirement exists because TB can spread between neighboring herds through shared fence lines, water sources, or wildlife contact well before symptoms appear in any single animal.

When a herd is confirmed positive, producers generally face one of two outcomes. When health officials find tuberculosis in a herd, it is managed by either depopulating the herd or by testing and removing reactor animals, since tuberculosis is not treated in livestock. There’s no antibiotic protocol that clears an infected herd for return to normal status; the disease has to be physically removed from the population.

Depopulation doesn’t automatically strip a state of its classification, either. If an affected herd is detected in a state or zone classified as accredited-free, and the herd is depopulated with an epidemiologic investigation completed within 90 days showing no evidence of spread, the state or zone may retain its accredited-free status. However, if two or more affected herds are detected in an accredited-free state or zone within a 48-month period, that state or zone will be removed from the accredited-free list and reclassified as modified accredited advanced. This is part of why states work hard to trace and resolve every detected case quickly.

Penalties for Non-Compliance in Mississippi

Mississippi backs its testing rules with real financial consequences. Each violation of the Board of Animal Health’s rules and regulations, or any other law governing the eradication of contagious diseases in animals and livestock, is subject to a civil penalty of up to $1,000, and when multiple animals are the subject of a single violation, each animal constitutes a separate violation. That per-animal structure means a producer moving a truckload of untested cattle could face penalties that multiply quickly rather than a single flat fine.

The penalty framework applies specifically to TB violations by name. Any person, firm, or corporation violating the rules and regulations of the Board of Animal Health relative to the control and eradication of tuberculosis, brucellosis, and a long list of other livestock and poultry diseases is subject to the provisions of Sections 69-15-53 through 69-15-69 of the Mississippi Code. Interfering with enforcement carries its own consequences as well. Any person, firm, or corporation failing to comply with quarantine provisions, or interfering with the State Veterinarian or a duly appointed officer in the discharge of duties, is subject to the penalties provided in Section 69-15-65 of the Mississippi Code.

Important Note: This article summarizes Mississippi Board of Animal Health regulations and Mississippi Code provisions for general informational purposes. Regulations are amended periodically, so producers should confirm current requirements directly with the Mississippi Board of Animal Health or a licensed accredited veterinarian before moving or testing livestock.

For producers, the practical takeaway is straightforward: test on schedule, keep official identification current, and never assume an exemption applies without checking the specific animal class against the current rule. Mississippi’s Chapter 12 entry requirements and the federal 9 CFR Part 77 tuberculosis rules both spell out the fine print, and the Uniform Methods and Rules for Bovine Tuberculosis Eradication covers the technical testing standards behind every requirement discussed above. Reviewing those primary sources alongside current guidance from APHIS’s bovine tuberculosis program before a sale, show, or interstate move is the simplest way to avoid a costly compliance gap.