Brucellosis Laws in Louisiana: What Cattle and Bison Owners Need to Know

Brucellosis is one of the most closely regulated livestock diseases in the United States, and for good reason. It spreads easily among cattle and bison, causes significant reproductive losses, and can infect people who come into contact with infected animals or consume contaminated dairy products. If you own or manage cattle, bison, or swine in Louisiana, understanding the state’s brucellosis laws is not optional — it is a core part of responsible and legally compliant herd management.

Louisiana has made enormous progress in eliminating brucellosis from its livestock population, but that progress depends on producers following a framework of vaccination, testing, movement, and reporting rules. This article walks you through every layer of that framework so you know exactly what is required of you under both Louisiana and federal law.

What Is Brucellosis and Why It Is Regulated in Louisiana

Brucellosis is a contagious bacterial disease caused by bacteria of the genus Brucella. It occurs mainly in cattle, bison, and swine, but can affect other animals including cervids, goats, sheep, and horses — and people. In cattle and bison, the bacteria of concern is Brucella abortus.

In its principal animal hosts, brucellosis causes loss of young through spontaneous abortion or birth of weak offspring, reduced milk production, and infertility. It can affect both animals and humans. In humans, brucellosis initially causes flu-like symptoms, but the disease may develop into a variety of chronic conditions, including arthritis. Humans can be treated for brucellosis with antibiotics.

There is no economically feasible treatment for brucellosis in livestock. That fact alone explains why prevention — through vaccination, testing, and movement controls — is the cornerstone of every state’s regulatory approach, including Louisiana’s.

A longstanding national eradication program mostly eliminated the disease in U.S. cattle. Louisiana’s brucellosis statutes, found primarily in Louisiana Revised Statutes Title 3, Part IV (§§ 3:2221–3:2232), establish the state-level framework for testing, vaccination, quarantine, and penalties that supports the federal eradication effort. The Louisiana Board of Animal Health may cooperate with the United States Department of Agriculture, APHIS Veterinary Services, in the expenditure of state and federal funds for employment of necessary personnel, purchase of equipment and supplies, payment of indemnity on brucellosis diseased cattle slaughtered under the program, and supervision of personnel and enforcement of regulations governing the eradication program.

Louisiana’s Brucellosis Classification Status

Louisiana holds the highest possible classification under the federal brucellosis system: Class Free status. USDA-APHIS declared Louisiana to be free of brucellosis, making it the 45th state to rid itself of the contagious disease affecting cattle and humans. Class Free status removes certain restrictions on the interstate movement of cattle from Louisiana.

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 abortus 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. States or areas that do not meet the minimum standards for Class C status are required to be placed under federal quarantine. Restrictions on moving cattle and bison interstate become less stringent as a state or area approaches or achieves Class Free status.

Under 9 CFR Part 78 Subpart E, Louisiana is listed among the Class Free states. States are designated brucellosis-free when they have no infected cattle or bison for 12 consecutive months under an active surveillance program, or additional surveillance measures in place around areas that have brucellosis-infected wildlife to ensure early detection of any disease spillover.

All 50 states, Puerto Rico, and the U.S. Virgin Islands are brucellosis-free, except for the occasional spillover of cases occurring in livestock near the Greater Yellowstone Area due to bison and elk having the disease. Louisiana’s geographic distance from the Greater Yellowstone Area means it faces minimal wildlife-spillover risk, but the state’s regulatory infrastructure remains active to protect that standing. For comparison, you can review how neighboring states handle their own programs, such as brucellosis laws in Missouri or brucellosis laws in Nebraska.

Vaccination Requirements in Louisiana

Louisiana’s vaccination rules apply primarily to female cattle participating in shows, fairs, breeders’ association sales, and similar events, as well as to herds seeking to maintain or regain clean status. The federally approved vaccine is RB51. There is a vaccine for brucellosis called RB51. Licensed for use in nonpregnant female cattle 4 to 12 months of age, the vaccine provides a significant level of protection — about 70 to 80 percent effective. It is also very effective at preventing abortions, which prevents further disease transmission. RB51 is available only through an accredited veterinarian, state animal health official, or federal area veterinarian in charge.

Under Louisiana Administrative Code Title 7, Part XXI, the state sets specific vaccination requirements for cattle admitted to exhibitions and sales:

• All heifers between four and 12 months of age must be official brucellosis calfhood vaccinates to be eligible to be shown in Louisiana.
• All heifers and cows over 12 months of age must be official brucellosis vaccinates or be from a herd that has had a complete negative herd test within the past 12 months and be tested negative to the brucellosis card test within 30 days prior to admission to fairs, livestock shows, and breeders’ association sales. A copy of the herd test record, which includes the animal(s) on the health certificate, must accompany the health certificate.
• No cattle from brucellosis quarantined herds or brucellosis quarantined areas are allowed to be exhibited in the state of Louisiana or consigned to breeders’ association sales in Louisiana.

During parishwide testing programs, Louisiana law gives producers an additional option. Any person owning or having charge of cattle being tested for brucellosis pursuant to a parishwide testing program, or which are being tested but have not shown evidence of brucellosis infection, may compel the Louisiana Board of Animal Health to vaccinate all of the mature female cattle, as well as all female calves over two months of age, with brucella abortus vaccine at the time of testing. The vaccination program shall be at the expense of the Louisiana Board of Animal Health.

All cattle so vaccinated shall be permanently identified at the time of vaccination with the official tattoo, patented by the United States Department of Agriculture, in the right ear. This permanent identification is critical for traceability throughout the animal’s life.

If you manage other livestock in Louisiana alongside your cattle, it is worth reviewing related regulatory frameworks such as goat ownership laws in Louisiana, since goats can also be susceptible to certain Brucella strains.

Testing Requirements for Cattle and Bison in Louisiana

Testing is the backbone of brucellosis eradication. In Louisiana, testing requirements are triggered by specific circumstances — suspected or confirmed infection, exhibition participation, interstate movement, and herd certification efforts.

Infected or exposed herds: Any person owning or having charge of any male or female cattle over eight months of age in a herd which has shown evidence of brucellosis infection, or has intermingled with or otherwise been exposed to brucellosis infected animals, upon at least thirty days prior written notification by an employee or authorized agent of the Louisiana Board of Animal Health shall present and restrain the cattle for identification and testing, and such infected herds shall be retested until these herds have become classified brucellosis negative as defined in rules and regulations of the Louisiana Board of Animal Health.

Evidence of infection includes finding one or more reactors to an official brucellosis agglutination test on animals bred on the farm, at livestock auction market, at a slaughter establishment or concentration point, or upon official report of a positive brucellosis result.

Exhibition testing: All bulls 12 months of age and over must be tested negative to the brucellosis card test within 30 days prior to admission to all fairs, livestock shows, breeders’ association sales, and rodeos. All bulls must be accompanied by a current health certificate.

Certified brucellosis-free herd testing: The following methods may be used to qualify a herd: by conducting at least two consecutive negative herd blood tests not less than 10 months nor more than 14 months apart; or, as an alternative for dairy cattle, by conducting a minimum of four consecutive negative brucellosis ring tests at not less than 90-day intervals, followed by a negative herd blood test within 90 days after the last negative ring test. Certified brucellosis-free herd status will remain in effect for one year beginning with the date of issuance of the certificate. A negative herd blood test must be conducted within 10 to 12 months of the last certification date for continuous status.

VS Form 4-54, Brucellosis Test Record — Market Cattle Testing Program, is used for brucellosis tests conducted as part of the Market Cattle Testing Program. This program governs the testing of cattle and bison at markets (first point of concentration) or slaughter. Louisiana producers should maintain copies of all test records, as these documents are routinely required for movement certificates and health certificates.

You can explore how neighboring states handle similar testing frameworks, including brucellosis laws in Minnesota and brucellosis laws in Michigan, for comparison.

Interstate and Intrastate Movement Rules in Louisiana

Louisiana’s Class Free status directly affects what is required when you move cattle or bison into or out of the state. Understanding both federal baseline rules and Louisiana-specific requirements is essential before any shipment.

Moving cattle out of Louisiana: Because Louisiana is a validated Class Free state, interstate movement requirements for animals are based upon the disease status of the individual animals or the herd or the state from which the animal originates. Animals originating from Louisiana generally face fewer restrictions when entering other Class Free states. However, the destination state’s rules always govern what testing or documentation is required upon arrival.

Before testing for interstate shipment, obtain state-specific regulations by contacting the state animal health official’s office in the importing state. Requirements vary considerably. Some states do not allow cattle or domestic bison to be moved interstate for breeding without a record of brucellosis vaccination.

Moving cattle into Louisiana: Animals entering Louisiana from other Class Free states face streamlined requirements. However, cattle originating from herds under quarantine or from states with active brucellosis concerns face stricter scrutiny. All animals entering Louisiana for exhibition must comply with the vaccination and testing requirements described in the vaccination and testing sections above.

Intrastate movement: The Uniform Methods and Rules contain minimum standards for certifying herds, classifying states and areas, and detecting, controlling, and eradicating brucellosis, as well as minimum brucellosis requirements for the intrastate and interstate movement of cattle and bison. Louisiana’s administrative rules implement these minimum standards and may apply additional requirements for certain categories of intrastate movement, particularly for animals being moved to fairs, shows, or sales.

Louisiana’s movement rules intersect with broader livestock regulations in the state. If you raise multiple species, it is also useful to understand the pet vaccination laws in Louisiana and how animal health documentation requirements apply across different contexts.

Reporting and Quarantine Requirements in Louisiana

When brucellosis is suspected or confirmed in a Louisiana herd, specific reporting and quarantine obligations are immediately triggered. These requirements exist at both the state and federal level.

Reporting obligations: Animal health professionals — including veterinarians, diagnostic laboratories, public health, zoo, or wildlife personnel, and others — report diagnosed or suspected cases of nationally listed reportable animal diseases to APHIS Area Veterinarians in Charge and to the state animal health official as applicable under state reporting regulations. Brucellosis is a nationally reportable disease, which means any confirmed or suspected case in Louisiana must be reported promptly.

Quarantine of exposed herds: When a herd tests positive or has been exposed to infected animals, the Louisiana Board of Animal Health has authority to place that herd under quarantine. Historically, Louisiana courts have upheld the Board’s authority to quarantine herds and seek mandatory injunctions to compel testing compliance under La. R.S. 3:2221. A quarantined herd cannot be moved or sold without authorization from the Board.

Branding of reactor animals: Any person owning or having charge of any cattle affected with brucellosis disease, as determined by official tests made by an employee or authorized agent of the Louisiana Board of Animal Health, shall on notification by the Louisiana Board of Animal Health present and restrain the cattle for identification and branding by an employee or authorized agent of the Louisiana Board of Animal Health. This branding requirement creates a permanent, visible record that the animal was a confirmed reactor.

Herd retesting: Infected herds shall be retested until these herds have become classified brucellosis negative as defined in rules and regulations of the Louisiana Board of Animal Health. Retesting continues on a schedule set by the Board until the herd achieves a clean classification.

If infection is suspected or confirmed, regulatory officials will contact you, the owner, or both, to develop a herd plan. An approved individual herd plan is a herd management and testing plan designed by the herd owner, the owner’s veterinarian if so requested, and a state representative or APHIS representative to determine the disease status of animals in the herd and to control and eradicate brucellosis within the herd. The plan must be jointly approved by the state animal health official and the Veterinarian in Charge.

Louisiana’s quarantine authority is part of a broader state animal disease control framework. If you are also interested in how Louisiana regulates other aspects of animal ownership, see the roadkill laws in Louisiana or backyard chicken laws in Louisiana for additional context on how the state approaches animal regulation generally.

Penalties for Brucellosis Violations in Louisiana

Louisiana law takes non-compliance with brucellosis regulations seriously. Penalties operate on two tracks: civil enforcement through injunctions and mandatory compliance orders, and criminal prosecution under the state’s agricultural statutes.

Mandatory injunctions: Louisiana courts have consistently upheld the Board of Animal Health’s authority to seek mandatory injunctions compelling cattle owners to present and restrain their animals for testing. Under La. R.S. 3:2221(C), a district court may issue an injunction ordering a producer to pen cattle for brucellosis testing when the statutory conditions for testing are met. Refusal to comply with a court-ordered injunction can result in contempt of court, with additional civil and potentially criminal consequences.

Criminal penalties under La. R.S. 3:2232: Louisiana’s brucellosis statutes include a criminal penalty provision under La. R.S. 3:2232. Louisiana courts have addressed the scope of these penalties, clarifying that they are enforceable through criminal prosecution. Violations of the brucellosis eradication statutes — including failure to present cattle for testing after proper notification, failure to comply with quarantine orders, and obstruction of Board agents — may expose a producer to criminal liability under this provision.

Federal consequences: The regulations of the APHIS Brucellosis Eradication Program vary based on the brucellosis status of each state. Minimum standards are set forth in the Brucellosis Eradication Uniform Methods and Rules; however, some states have more restrictive requirements. Violations of federal movement regulations under 9 CFR Part 78 — such as moving quarantined animals across state lines without authorization — can trigger federal enforcement actions separate from any state penalties.

Louisiana’s penalty framework reflects the state’s commitment to protecting its Class Free status and the broader livestock industry. Producers who stay current on vaccination records, respond promptly to testing notifications, and work cooperatively with the Louisiana Board of Animal Health and USDA-APHIS are best positioned to avoid enforcement actions altogether.

For a broader look at how brucellosis laws vary across the country, you can also review brucellosis laws in Nevada. And if you manage multiple animal species on your Louisiana property, resources like beekeeping laws in Louisiana and kennel zoning laws in Louisiana can help you stay fully informed across all areas of state animal regulation.