Bovine Tuberculosis Testing Requirements in Texas: What Cattle Owners Must Know
August 22, 2026
Texas lost its TB-free status once already, and getting it back took years of retesting nearly every dairy in the state. That history is why bovine tuberculosis testing requirements in Texas remain some of the strictest livestock health rules in the country today. If you own, transport, or sell cattle in Texas, understanding these rules protects your herd’s marketability and keeps the state’s disease-free standing intact.
This guide walks through who has to test, which methods the Texas Animal Health Commission (TAHC) accepts, and what happens if an animal comes back positive. You will also find the movement rules that apply whether you are hauling cattle across county lines or bringing them in from another state or from Mexico.
What Is Bovine Tuberculosis and Why It Is Regulated in Texas
Cattle tuberculosis (TB) is a contagious, chronic, respiratory disease caused by the bacterium Mycobacterium bovis (M. bovis). The bacterium is properly written as Mycobacterium bovis, and it does not confine itself to cattle. This strain of TB can also affect other species of animals including elk, deer, bison, goats, dogs, and other species, which is part of why the disease draws such close regulatory attention across the livestock and companion-animal world alike. If you also keep dogs on your property, TAHC’s cross-species concern is one more reason to stay current on rabies vaccine requirements for dogs in Texas, since both diseases fall under the state’s broader zoonotic disease control framework.
TB has a long incubation period lasting months to years and was once the most prevalent infectious disease of cattle and swine in the United States. Through a cooperative state-federal program, bovine tuberculosis has been nearly eradicated from livestock in the US. To protect Texas animals from TB, the USDA and TAHC have regulations in place to prevent the introduction and spread of TB, and those regulations outline requirements for movement, testing, identification, record keeping, surveillance, and approved facilities.
Key Insight: TB is not treated in livestock. There is no approved cure for infected cattle, which is exactly why testing, movement control, and depopulation carry so much regulatory weight in Texas rather than veterinary treatment protocols.
Because TB spreads slowly and often shows no outward symptoms until a herd is deeply affected, Texas leans on the same disease-control philosophy it applies elsewhere in animal health, including programs like rabies vaccine requirements in Texas: identify carriers early, restrict movement, and stop transmission before it reaches other herds or, in TB’s case, other species.
Texas’s TB Classification Status and Risk Zones
Texas has not always held clean TB status. In 2000, Texas won a battle against cattle TB, earning the U.S. Department of Agriculture’s TB accredited-free status, but in 2002 that status was revoked when two infected cattle herds were detected. The entire state was then classified as modified accredited advanced for cattle and bison starting June 3, 2002. After extensive testing, Texas regained its TB-free status from USDA in October 2006, an effort that included testing 2,014 purebred beef operations and all 818 of the state’s dairies.
The federal government formally amended the bovine tuberculosis regulations regarding state and zone classifications by raising the designation of Texas from modified accredited advanced to accredited-free after determining Texas met the criteria for that designation, with the change taking effect September 29, 2006. Texas has held accredited-free status since, but that status is not permanent by default.
| Classification | Herd Infection Threshold | Minimum Age of Cattle Tested |
|---|---|---|
| Accredited-Free | Loses status if two or more affected herds are found within a 48-month period | 24 months of age and older |
| Modified Accredited Advanced | Fewer than 0.01% of herds affected for each of the most recent 2 years | 18 months of age and older |
| Modified Accredited | Fewer than 0.1% of herds affected for the most recent year | 12 months of age and older |
| Accreditation Preparatory | Fewer than 0.5% of total herds affected in the state or zone | All cattle and bison regardless of age |
Within an accredited-free state, geography still matters. As a result of persistent TB confirmations in El Paso and Hudspeth counties, TAHC established a Movement Restriction Zone (MRZ) in 2001. That zone remains a distinct risk area within the state, meaning cattle originating there may face additional testing scrutiny compared to herds elsewhere in Texas. If you operate near this border region, confirm your zone status directly with your TAHC regional office before moving any animals.
Who Must Test and Which Animals Are Covered in Texas
TB testing obligations in Texas apply most heavily to cattle and bison, but the rules scale depending on the animal’s age, breed, sex, and where it is headed. All cattle and bison in an accredited herd must be free from tuberculosis to maintain that herd’s certification, and herd owners bear the ongoing compliance burden rather than the state.
Several categories of cattle face the most frequent testing requirements:
- Sexually intact dairy cattle moving into or within Texas, which face tighter testing windows than beef cattle
- Cattle originating from Mexico, subject to mandatory post-entry retesting and permanent identification
- Roping and rodeo steers with Mexican origin (“M” brand), which require annual retesting for as long as they remain in the country
- Herds seeking or maintaining TB-accredited status, which must complete periodic whole-herd testing on a schedule tied to the state’s classification
- Animals with wildlife TB exposure risk, including cattle from areas with an identified wildlife reservoir for the disease
Wildlife susceptibility is not incidental to this framework. A variety of other species may be susceptible to cattle tuberculosis, including captive elk and exotic deer, bison, goats, swine, humans, and cats, though sheep and horses are rarely affected. If you hunt or manage exotic cervids on your land, it is worth reviewing hunting license requirements in Texas alongside your herd’s biosecurity plan, since wildlife reservoirs factor directly into a region’s TB risk classification.
Approved TB Testing Methods in Texas
TAHC and USDA rely on a tiered testing approach rather than a single test, moving from a broad screening tool to more specific confirmatory tests when needed. Only bovine purified protein derivative tuberculin (PPD bovis) licensed by USDA may be used for official testing, and diagnosing TB in live animals depends on using an effective testing technique with an intradermal injection of tuberculin obtained through the state animal health official or APHIS-VS area offices.
| Test | Purpose | Key Detail |
|---|---|---|
| Caudal Fold Test (CFT) | Primary screening test | A positive reaction is a delayed hypersensitivity swelling that usually begins within 8 to 12 hours and peaks about 72 hours after injection |
| Comparative Cervical (CC) Test | Confirmatory follow-up | Used when the caudal-fold test produces a suspect result requiring further evaluation |
| Gamma Interferon Test | Confirmatory follow-up | Blood-based test used alongside or instead of the CC test for suspect animals |
| Slaughter Inspection | Passive surveillance | Most cattle TB is detected through carcass inspection at slaughter plants, where lesions identified by inspectors are collected and forwarded to a laboratory for confirmation |
Test administration follows strict documentation rules. Test observation without palpation is unacceptable, and results must be recorded on VS Form 6-22, with an entry of “N” for negative when no change is observed at the injection site, or “S” for suspect when any increase in caudal fold thickness, size, or sensitivity is observed or palpated. 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.
Pro Tip: If you already schedule annual health checks for other required tests, such as the EIA Coggins test requirements in Texas for horses on a mixed-livestock property, ask your accredited veterinarian to coordinate TB tuberculin testing on the same visit to reduce handling stress and veterinary costs.
Interstate and Intrastate Movement Testing Requirements in Texas
Movement rules vary sharply depending on where cattle originate and what type of animal is moving. Generally, agricultural animals entering Texas must be accompanied by a Certificate of Veterinary Inspection or Health Certificate issued by a veterinarian within 30 to 45 days prior to entry. For sexually intact dairy cattle specifically, animals six months of age or older may enter provided they are officially identified and accompanied by a certificate of veterinary inspection stating they were negative to an official tuberculosis test conducted within 60 days prior to entry, unless they originate from a tuberculosis-accredited herd or are moving directly to an approved slaughtering establishment, which exempts them from the test requirement.
Younger dairy cattle face a different path. Sexually intact dairy cattle less than six months of age must obtain an entry permit and be held at a designated facility until tested negative between two and six months of age.
Cattle imported from Mexico face the most rigorous requirements in the entire framework:
- All cattle moved into Texas from Mexico must be identified with an “M” brand prior to moving to a destination in Texas
- Cattle must be moved by permit to a premise of destination and remain under Hold Order, restricting movement, until permanently identified and retested for tuberculosis between 60 and 120 days after entry at the owner’s expense
- After that, cattle must be retested for tuberculosis annually at the owner’s expense, with test records maintained with the animal and available for review
- Regardless of reproductive status, test history, or Mexican state of origin, Holstein and Holstein-cross cattle are prohibited from entering Texas
Roping and rodeo cattle get a narrower exception. “M” brand steers recognized as potential rodeo or roping stock being imported into Texas from another state must obtain a permit prior to entry and be accompanied by a certificate of veterinary inspection showing a negative TB test within 12 months prior to entry. Roping steers from Mexico with an “M” brand on their right hip must be accompanied by an annual test for tuberculosis for as long as they stay in the state.
Whether you are transporting cattle across the state line or just moving them between pastures within Texas, having compliant hauling equipment matters just as much as paperwork. Review livestock trailer requirements in Texas before any move that involves crossing county or state lines with tested or permitted animals.
Movement conditions can also shift with little notice. Effective May 11, 2025, USDA APHIS in conjunction with Customs and Border Protection restricted the importation of live animal commodities originating from or transiting Mexico due to New World screwworm, and the import suspension has persisted on a month-by-month basis until containment is achieved. Dairy operations face an added federal layer as well: the National Milk Testing Strategy includes mandatory testing for interstate movement of lactating dairy cattle under Federal Orders issued April 24 and December 6, 2024. Always confirm current entry conditions with TAHC’s entry requirements page before scheduling a move, since these federal orders can change the testing calculus quickly.
What Happens When a Suspect or Positive Result Occurs in Texas
A “suspect” caudal-fold result does not automatically mean confirmed TB, but it does trigger a defined response chain. 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. If the test produces any type of response, the accredited veterinarian must immediately notify APHIS-VS Area Offices and state animal health officials.
From there, investigators work to contain any potential spread. Efforts are made to trace or “trace” the animal back to its herd of origin so that herd-mates or other exposed cattle can be tested, and all livestock herds within a 10-mile radius will be tested within six months of any diagnosis of bovine tuberculosis.
Important Note: A single confirmed case does not necessarily strip Texas of its accredited-free status. If an affected herd is detected in an accredited-free state or zone, and the herd is depopulated with an epidemiologic investigation completed within 90 days showing no evidence of spread, the state may retain its accredited-free status. However, if two or more affected herds are detected in an accredited-free state within a 48-month period, the state will be reclassified as modified accredited advanced, which would tighten testing requirements statewide.
This is exactly the scenario Texas has lived through before. In one instance, a federal testing laboratory confirmed cattle from two dairies in Castro County tested positive for the disease, prompting the Texas Animal Health Commission to immediately begin testing dairy, calf-raising, and dairy heifer-raising operations with epidemiological links to the infected herds, illustrating how quickly a single positive result can expand into a regional testing effort.
Quarantine and Herd Depopulation Rules in Texas
TAHC distinguishes between two levels of movement restriction depending on how confirmed the exposure is. TAHC will issue a “Hold Order” to restrict movement of animals suspected of exposure to a disease, while a “Quarantine” is used to restrict movement of known positive animals. These tools give the state a graduated response rather than an all-or-nothing shutdown, letting officials contain risk without unnecessarily restricting unaffected herds.
When a herd is confirmed positive, depopulation is often the fastest path back to normal operations for the surrounding region, even though it is costly for the affected owner. Completing depopulation along with an epidemiologic investigation within 90 days, with no evidence of disease spread, allows the state or zone to retain its accredited-free status rather than face a statewide reclassification.
Depopulation rules extend beyond the original affected animals. 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 it would to cattle and bison. In cases involving wildlife or exhibition animals with TB exposure, a management plan must include provisions for immediate investigation, prevention of spread to other animals and wildlife, increased surveillance, eradication from individual herds, a timeline for eradication, and performance standards to measure yearly progress. If a state or zone fails to implement such a plan within six months, it loses accredited-free status and is reclassified as modified accredited advanced, which is a serious enough consequence that TAHC treats these timelines as hard deadlines rather than guidelines.
Penalties for Non-Compliance in Texas
Texas backs its TB testing and movement rules with real enforcement teeth. A person who violates a rule or order under the Texas Animal Health Commission’s chapters is subject to administrative penalties, criminal penalties, sanctions, and civil remedies under state law. TAHC’s statutory authority is detailed in Title 6, Subtitle C, Control of Animal Diseases and Pests, Chapters 161 through 168, of the Texas Agriculture Code, which gives the agency broad authority to test, restrict movement, and penalize non-compliant owners.
Compliance oversight is not purely reactive on TAHC’s end. Anyone with information concerning a suspected violation of TAHC rules is encouraged to file a complaint according to the agency’s established process, which means neighboring producers and veterinarians play a direct role in flagging non-compliant movement or testing gaps. If you believe an animal has been moved or sold without meeting testing requirements, TAHC’s complaint process is the correct channel rather than local law enforcement.
Owners disputing a testing or quarantine decision are not without recourse. Appeals of orders and decisions of the executive director concerning tuberculosis are governed by a specific general requirements section within TAHC’s rules, giving producers a formal path to contest a hold order or quarantine designation they believe was applied incorrectly. Given how much is at stake, from herd value to interstate marketability, most producers find it worthwhile to consult TAHC directly or an accredited veterinarian the moment a testing question comes up rather than risk a violation. You can review the full rule text in the TAHC Complete Rules document for the exact enforcement provisions that apply to your situation.
Bovine tuberculosis testing requirements in Texas exist because the state has already paid the price of losing accredited-free status once. Whether you are moving cattle across a state line, importing from Mexico, or simply maintaining herd records for TB-free certification, following TAHC’s testing, identification, and movement rules protects both your operation and the broader Texas cattle industry. When in doubt about a specific testing window, permit, or classification question, TAHC’s regional offices and your accredited veterinarian remain the most reliable sources for guidance specific to your herd.