Brucellosis Laws in Texas: What Cattle and Bison Owners Need to Know
August 21, 2026
Brucellosis is one of the most tightly regulated livestock diseases in the United States, and Texas is no exception. If you raise cattle, bison, or swine in the Lone Star State, understanding the rules surrounding brucellosis is not optional — it is a legal obligation that can affect your ability to move animals, sell livestock, and maintain your herd’s standing with state and federal authorities.
Texas Agriculture Code Chapter 163 and the Texas Animal Health Commission (TAHC) rules under Title 4, Part 2 of the Texas Administrative Code form the backbone of brucellosis regulation in the state. This guide walks you through every major requirement so you know exactly where you stand.
What Is Brucellosis and Why It Is Regulated in Texas
Brucellosis is a contagious bacterial disease caused by organisms in the Brucella genus. It is a costly disease of ruminants and other animals that can also affect humans, and it is mainly a threat to cattle, bison, and swine. In cattle, the disease is caused specifically by Brucella abortus (B. abortus), while swine are primarily affected by Brucella suis.
The disease causes decreased milk production, weight loss in animals, loss of young, infertility, and lameness — and there is no known effective treatment. Because of these consequences, the economic stakes for Texas cattle producers are significant.
B. abortus primarily affects cattle, bison, and cervids. Brucellosis is a zoonotic disease that can affect humans, but eradication efforts along with modern sanitary practices and pasteurization of milk products have greatly decreased the frequency of human infections. From a public health standpoint, brucellosis is a bacterial infection that spreads from animals to humans, primarily affecting those in contact with infected livestock or consuming unpasteurized dairy products.
In order to protect Texas animals from bovine brucellosis, the TAHC and USDA have regulations in place to prevent the introduction and spread of brucellosis, outlining requirements for movement, testing, identification, record keeping, surveillance, and Certified Brucellosis Free Herds. On the human side, several Texas laws — including the Texas Health and Safety Code, Chapters 81, 84, and 87 — require specific information regarding notifiable conditions to be provided to the Texas Department of State Health Services, and healthcare providers, hospitals, and laboratories must report patients suspected of having a notifiable condition.
If you also keep goats or other livestock on your property, be aware that brucellosis regulations may intersect with other animal ownership rules. You can review goat ownership laws in Texas for additional context on how disease regulations apply to small ruminants.
Texas’s Brucellosis Classification Status
Understanding Texas’s official brucellosis classification is essential because it directly determines what testing and movement restrictions apply when you bring animals into or out of the state.
The brucellosis regulations contained in 9 CFR Part 78 provide a system for classifying states or portions of states according to the rate of Brucella infection present and the general effectiveness of a brucellosis control and eradication program. The classifications are Class Free, Class A, Class B, and Class C.
Texas was upgraded from Class A to Class Free status, and the state has met all the standards for that classification. The brucellosis Class Free classification is based on a finding of no known brucellosis in cattle for the 12 months preceding classification as Class Free. This upgrade, which became effective February 1, 2008, significantly reduced restrictions on interstate cattle movement from Texas.
Restrictions on moving cattle interstate become less stringent as a state approaches or achieves Class Free status. For Texas producers, this means you are no longer required to test cattle before interstate movement simply because of the state’s classification — though other specific circumstances may still trigger testing requirements.
For comparison, you may find it useful to review how neighboring states handle their own classifications. See our guides on brucellosis laws in Nebraska and brucellosis laws in Missouri to understand how Texas’s Class Free status differs from states still working toward eradication.
Vaccination Requirements in Texas
Texas law grants the TAHC broad authority to regulate brucellosis vaccination. The commission may by rule regulate and require the vaccination of female cattle within all or any of the area classifications, and among other rules, the commission may adopt rules providing for the identification of cattle to be vaccinated.
For most Texas cattle producers, official vaccination is strongly recommended even when not strictly mandated for all animals. It is recommended that all female cattle between four and 12 months of age being purchased or sold for use in grazing, breeding, or dairying operations be officially vaccinated.
- Who should be vaccinated: Female calves between 4 and 12 months of age intended for grazing, breeding, or dairy use
- Who administers vaccines: Only authorized, commission-approved personnel may administer brucellosis vaccines
- Approved products only: All vaccines must be approved by the TAHC before use
The vaccine authorization rules are strict. A person may not sell a brucellosis antigen or vaccine unless the antigen or vaccine is approved by the commission, and a person may not administer a brucellosis antigen or vaccine unless the antigen or vaccine is approved by the commission and the person is authorized by the commission to administer it.
For swine producers, vaccination rules differ. All breeding swine must have negative brucellosis and pseudorabies (PRV) test results prior to change of ownership. This requirement applies regardless of the commercial or backyard status of your operation.
Testing Requirements for Cattle and Bison in Texas
Testing is the cornerstone of Texas’s brucellosis eradication program. The commission by rule shall prescribe criteria for classifying cattle as negative, infected with brucellosis, or suspected of being infected with brucellosis. Each classification must be based on the testing of cattle, which may include serological testing, microbiological culturing of blood, tissue, secretions, or excretions, or both.
If you want your herd to carry Certified Brucellosis Free Herd status — which opens doors for movement and marketing — the testing requirements are specific. All cattle, except steers and spayed heifers, are subject to test requirements at 18 months of age. Testing is conducted on a herd basis including all offspring that are of an age to be tested, and certified free herd status is valid for a 12-month period.
To qualify for initial certification, your herd may use one of several approved methods:
- Brucellosis Milk Surveillance Test (BMST): A minimum of four consecutive, negative brucellosis milk surveillance tests conducted at not less than 90-day intervals, followed by a negative herd blood test conducted within 90 days after the last negative brucellosis milk surveillance test.
- Complete herd blood test: A full serological blood test of all eligible animals in the herd.
- Combination methods: The commission permits qualifying through one or more of the above methods, depending on herd type and management practices.
To enter the certified free herd program, you must complete and sign a herd plan agreement with the Texas Animal Health Commission and the USDA, Animal and Plant Health Inspection Service and Veterinary Services, and testing will be conducted on a herd basis including all offspring that are of an age to be tested.
The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) serves as the state-federal testing laboratory for brucellosis. TVMDL offers several testing methods to detect brucella across a variety of species, and as the state-federal testing laboratory, TVMDL also performs all regulatory tests for brucella.
| Animal Category | Testing Requirement | Notes |
|---|---|---|
| Intact female cattle/bison (18+ months) | Required for certified herd status | Steers and spayed heifers are exempt |
| Dairy herds | BMST or herd blood test | Minimum 4 consecutive negative BMST tests |
| Breeding swine | Required before change of ownership | Negative test required prior to sale |
| Cattle entering from foreign countries (non-comparable status) | Post-entry testing required | 60–120 days post-entry for intact females |
Interstate and Intrastate Movement Rules in Texas
Moving cattle and bison across state lines — or even within Texas under certain conditions — triggers specific brucellosis-related requirements. The TAHC holds broad authority in this area. As a control measure, the commission by rule may regulate the movement of cattle. The commission may restrict the intrastate movement of cattle even though the movement of the cattle is unrestricted in interstate or international commerce, and the commission may require testing, vaccination, or another procedure that is epidemiologically sound before or following the movement of cattle.
Because Texas holds Class Free status, cattle moving out of Texas face fewer federal restrictions than animals from lower-classified states. Cattle and bison that are to be moved interstate from Class A states, except those moving directly to slaughter or to quarantined feedlots, must be tested before they are eligible for movement — but attaining Class Free status allows producers in Texas to forgo the cost of this test.
For cattle entering Texas from other countries, the rules are more demanding:
- Sexually intact cattle must obtain an “E” permit from the TAHC prior to moving to a destination in Texas other than direct to slaughter, quarantined feedlot, or designated pens, and the permit number must be entered on the Importation Certificate (VS Form 17-30) with a copy forwarded to the TAHC’s central office in Austin immediately following issuance.
- Intact female cattle must be tested for brucellosis 60 to 120 days post-entry, or other time frames as approved by the TAHC to accommodate unique management practices, at the owner’s expense, and the test records must be maintained with the animal and available for review.
For cattle entering from other U.S. states, agricultural animals entering Texas are subject to health and testing requirements, and generally must be accompanied by a Certificate of Veterinary Inspection (CVI) issued by a veterinarian within 30 to 45 days prior to entry.
If you are also importing other types of animals into Texas, it is worth reviewing the broader pet import laws in Texas to understand how the state’s entry requirements apply across different species. For additional state-by-state comparison on movement rules, see our guides on brucellosis laws in Michigan and brucellosis laws in Minnesota.
Reporting and Quarantine Requirements in Texas
If brucellosis is detected in your herd, you have both legal obligations and procedural steps to follow immediately. Texas treats brucellosis as a reportable disease, and failure to report can carry its own consequences.
The Texas Animal Health Commission (TAHC), under Chapter 161, oversees disease control programs and enforces mandatory testing, vaccination, and reporting. Reportable diseases such as bovine tuberculosis, brucellosis, and equine infectious anemia must be reported immediately, or ranchers risk quarantines and movement restrictions.
On the human health side, any suspect cases of brucellosis must be reported to your local health authority within one working day, or by calling the Department of State Health Services at 1-800-252-8239. Case clusters or multiple cases should be reported immediately.
When an animal tests positive, the following steps apply under Texas law:
- Notification of the owner: If a tested animal shows evidence of infection with brucellosis, the person performing the test shall handle the animal in accordance with the rules of the commission. The commission may require the person performing the test to furnish the owner with written data showing that the animal is infected, fire brand the animal on the left jaw with the letter “B,” place an approved numbered identification on the animal, and report the identification number in writing to the commission.
- Quarantine of the herd: The entire herd of which the infected animal is a part must be handled according to TAHC rules, which can include quarantine, supervised slaughter, or depopulation depending on the severity of the case.
- TAHC notification of the Texas Department of Health: The TAHC shall establish quarantines upon infected and exposed animals and premises, advise the owner or caretaker how to properly dispose of carcasses, and require such treatment and vaccination as may be necessary to control and eradicate the disease. TAHC will notify the Texas Department of Health of the quarantine.
- Quarantine release conditions: If a retest of a certified herd reveals only one reactor, the certification status will be suspended until all provisions for release of quarantine have been met. If more than one reactor is disclosed, the herd certification is terminated until all provisions for release of quarantine have been met.
In severe cases, the TAHC can order herd depopulation to contain contagion. This is an extreme measure, but it underscores why early detection and reporting are so important.
You can file a complaint or report a suspected violation with the TAHC through multiple channels. You can submit a written complaint through the TAHC online portal, by email at tahc-complaints@tahc.texas.gov, by mail to the Texas Animal Health Commission Legal and Compliance Department in Austin, or by phone at 1-800-550-8242.
Texas animal health regulations also extend to other livestock species. If you keep pigs on your property, review our guide on backyard pig laws in Texas, as swine brucellosis reporting requirements apply to domestic pigs as well.
Penalties for Brucellosis Violations in Texas
Texas law establishes a tiered penalty structure for brucellosis violations under Agriculture Code Chapter 163, Subchapter F. The severity of the penalty generally tracks the nature and willfulness of the violation.
The key criminal offenses and their classifications are as follows:
| Violation | Classification | Escalation |
|---|---|---|
| Improper sale or administration of brucellosis vaccine or antigen | Class A misdemeanor | No escalation provision noted |
| Knowingly moving an animal in violation of TAHC rules | Class C misdemeanor | Class B misdemeanor on second conviction |
| Slaughter plant failure to collect/submit blood samples | Class C misdemeanor | Class B misdemeanor on second conviction |
| Knowingly refusing to handle an infected animal per TAHC rules | Criminal offense under §163.085 | Severity based on circumstances |
| Refusing to vaccinate female calves as required | Criminal offense under §163.081 | Per commission rules |
Breaking these down in more detail:
Vaccine violations: A person commits an offense if the person sells or administers a brucellosis antigen or vaccine in violation of Section 163.064 of the code, and this offense is a Class A misdemeanor.
Illegal movement of animals: A person, including a railway or a common carrier, commits an offense if the person knowingly moves an animal in violation of a rule of the commission. An offense under this section is a Class C misdemeanor unless it is shown on the trial of the offense that the defendant has been previously convicted under this section, in which event the offense is a Class B misdemeanor.
Slaughter plant non-compliance: The owner or operator of a slaughter plant commits an offense if the slaughter plant fails to comply with blood sample collection requirements or a rule adopted under this section. An offense under this subsection is a Class C misdemeanor unless it is shown on the trial of the offense that the defendant has been previously convicted under this section, in which event the offense is a Class B misdemeanor.
Failure to handle infected animals: A person commits an offense if the person knowingly refuses to handle in accordance with the rules of the commission an animal that the commission has classified as infected with brucellosis.
If you receive a violation notice from the TAHC, within ten working days of receipt of a complaint, TAHC will send an acknowledgement to the complainant. TAHC will then make an initial assessment of the complaint details to determine if there is a violation of a commission rule, and if a violation has occurred, TAHC will take appropriate actions to remedy the problem and prevent further violations.
Understanding brucellosis penalties is just one piece of Texas’s broader animal regulation landscape. For more on how Texas regulates animal ownership and related activities, explore our guides on pet laws in Texas, beekeeping laws in Texas, and backyard chicken laws in Texas.
Conclusion
Texas takes brucellosis regulation seriously, and for good reason — the disease threatens livestock productivity, interstate commerce, and public health. As a cattle, bison, or swine owner in Texas, your core obligations come down to four areas: understanding the state’s Class Free classification and what it means for movement, following vaccination protocols for eligible female cattle, maintaining testing records and pursuing Certified Brucellosis Free Herd status if you sell or move animals regularly, and reporting any suspected infections to the TAHC immediately.
The TAHC is your primary point of contact for all brucellosis-related compliance questions. You can reach them at 1-800-550-8242 or visit the TAHC Cattle and Bison page for the most current rules. For official statutory language, review Texas Agriculture Code Chapter 163 directly. Staying proactive — vaccinating eligible animals, testing on schedule, and keeping thorough records — is always less costly than dealing with a quarantine or a criminal violation after the fact.