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

Brucellosis is one of the most closely regulated livestock diseases in the United States, and Oregon has built a detailed legal framework around its prevention, detection, and control. If you own cattle or bison in Oregon — or move animals across state lines — understanding these rules is not optional. Violations can result in quarantines, loss of indemnity eligibility, and financial penalties.

This guide walks you through every major layer of Oregon’s brucellosis regulations: what the disease is, how the state is classified, what vaccination and testing rules apply, how movement is governed, and what happens when violations occur.

What Is Brucellosis and Why It Is Regulated in Oregon

Brucellosis is a contagious, infectious, and communicable disease affecting primarily cattle, bison, and swine, caused by bacteria of the genus Brucella. Brucella abortus affects mainly bovine species, while B. suis affects mainly porcine species. Goats, sheep, and horses are also susceptible to B. abortus, and a third strain, B. melitensis, affects mainly goats and sheep and is considered a foreign animal disease.

In its principal animal hosts, brucellosis causes loss of young through spontaneous abortion or birth of weak offspring, reduced milk production, and infertility. Both animals and humans can be affected, and it is mainly transmitted from animals by direct contact with infected blood, placenta, fetuses, or uterine secretions, or through the consumption of infected products.

Brucella abortus can be a serious, debilitating, and sometimes chronic human pathogen that may affect a variety of organs. Most human cases are the result of occupational exposure to infected animals, but infections can also occur from ingesting contaminated dairy products, especially unpasteurized milk.

The disease has significant consequences for animal health, public health, and international trade. That intersection of concerns — livestock productivity, human safety, and export markets — is precisely why Oregon maintains an active regulatory framework even though the disease has not been detected in Oregon livestock for decades.

If you raise livestock in Oregon, you should also be familiar with related state animal regulations, including goat ownership laws in Oregon and backyard chicken laws in Oregon, which address disease reporting and animal health requirements for other species.

Oregon’s Brucellosis Classification Status

Oregon is classified by the USDA as free of brucellosis. This designation carries real legal and practical weight. States are designated brucellosis-free when they have no infected cattle or bison for 12 consecutive months under an active surveillance program, or when additional surveillance measures are in place around areas that have brucellosis-infected wildlife to ensure early detection of any disease spillover.

This disease has been eradicated in Oregon since January 14, 1993. The last case of brucellosis in Oregon livestock was approximately 25 years ago in Klamath County. Oregon is listed among the validated brucellosis-free states under federal regulations at 9 CFR Part 78, which governs interstate movement and classification standards nationwide.

The federal classification system uses four tiers — Class Free, Class A, Class B, and Class C — and restrictions on moving cattle and bison interstate become less stringent as a state approaches or achieves Class Free status.

There is a Designated Surveillance Area (DSA) where wild cervid populations are infected with brucellosis, which includes Montana, Wyoming, and Idaho. Those states follow a rigorous management surveillance program that includes testing every animal prior to leaving the Greater Yellowstone Surveillance Area for brucellosis and vaccinating cattle between 4 and 12 months of age. Cattle can leave the GYSA if they are vaccinated and negative for brucellosis, making the risk relatively low for other cattle in other states.

For a comparison of how neighboring states handle classification and regulation, see the guides on brucellosis laws in Nevada and brucellosis laws in Nebraska.

Vaccination Requirements in Oregon

Oregon’s vaccination landscape changed significantly on January 1, 2024. During the 2023 Oregon Legislative Session, the legislature passed Senate Bill 57, which was signed into law by Governor Kotek on June 6, 2023. Senate Bill 57 removed the statutory requirement for brucellosis vaccination in Oregon effective January 1, 2024.

Before SB 57 took effect, Oregon required all female cattle to be vaccinated between four and twelve months of age, and unvaccinated females could only be sold directly to licensed slaughter facilities. The rationale for removing the mandate was straightforward: eradication efforts had rendered the disease risk “minimal to non-existent,” though the vaccine requirement continued to add costs for producers while simultaneously lowering the value of unvaccinated cows.

California removed their vaccination requirement in 2020, as did Colorado several years before that. Oregon’s move aligned it with a broader regional trend among Western states.

When vaccination does occur — whether voluntarily or as a condition of interstate movement — Oregon’s administrative rules specify the exact procedure. Official calfhood vaccination may only be performed by an accredited veterinarian on female cattle and bison when more than 4 months of age and less than 12 months of age, and the veterinarian must follow the official calfhood vaccination protocol in the Brucellosis Eradication: Uniform Methods and Rules dated October 1, 2003.

To be an official calfhood vaccinate, the vaccinated bovine or bison calf must be given a subcutaneous 2-mL dose of Brucella abortus Strain RB51 vaccine and permanently identified as a calfhood vaccinate by tattoo in the right ear.

Oregon also allows a “mature vaccination” option for animals that were not vaccinated as calves. Oregon regulations allow healthy females of breeding age, which were not vaccinated as calves, to be vaccinated for brucellosis after twelve months of age. However, the USDA does not recognize Mature Vaccination as “official vaccination,” and many states will not accept mature vaccinated cattle.

The mature vaccination procedure has additional requirements:

• A blood sample must be drawn at the time of vaccination and sent to an official laboratory for brucellosis testing. Mature vaccinated cattle must be held under quarantine until blood testing results are returned.
• Mature vaccination dosage is 1 mL of normally reconstituted RB51 brucellosis vaccine, administered subcutaneously.
• An official brucellosis vaccination steel identification tag shall be applied to the right ear of the vaccinated animal, along with an official brucellosis tattoo. The tattoo is the letter “M” followed by the official USDA vaccination shield, followed by the last digit of the year of vaccination.

Before sending mature vaccinated cattle interstate, check with the state of destination to determine their policy on mature vaccinates. This step is critical to avoid movement violations.

Testing Requirements for Cattle and Bison in Oregon

Oregon’s testing requirements are tied directly to the state’s Class Free status and to where animals originate. Because Oregon holds Class Free designation, routine pre-movement testing is not required for most in-state transactions, but specific circumstances do trigger mandatory testing.

All eligible cattle not originating in a Designated Area are specifically exempt from brucellosis testing before entry into the State of Oregon. The key variable is whether the animals come from a Designated Area — defined under Oregon Administrative Rules as an area, herd, or herds described by USDA and/or the State Animal Health Official of the state of origin as containing cattle potentially infected with or exposed to brucellosis and thereby subject to movement restrictions and/or additional testing.

For mature vaccination situations, testing is mandatory and non-negotiable. As noted above, a blood sample must be drawn at the time of vaccination and submitted to an official laboratory. This requirement applies regardless of whether the animal is already on an Oregon farm or is being brought in from another state.

For dairy herds, the brucellosis ring test (BRT) is a standard surveillance tool used on composite milk or cream samples. Herds that are negative to the brucellosis ring test and that are not quarantined as brucellosis affected are classified as brucellosis negative for public health ordinances and surveillance purposes. Herds classified as suspicious require a herd blood test to determine animal and herd status.

Oregon participates in the national surveillance program administered by USDA APHIS. Federal and state animal health officials jointly conduct surveillance for bovine brucellosis. When infected animals are identified, officials investigate these cases to determine if additional animals or herds are infected.

Interstate and Intrastate Movement Rules in Oregon

Movement rules are among the most operationally complex parts of Oregon’s brucellosis framework. Whether you are bringing cattle into Oregon or shipping them out, the rules differ based on origin, destination, and intended use.

Importing Cattle Into Oregon

Under OAR 603-011-0270, cattle entering Oregon for breeding or dairy purposes face the most scrutiny. All sexually intact cattle over 4 months not originating from a Designated Area and consigned to an approved state-federal market, which upon sale are to go to ranches or farms in Oregon for breeding and/or dairy purposes, must be vaccinated for brucellosis. Evidence of such vaccination is an official tattoo and/or official vaccination tag in the right ear of the animal, and the cost of vaccination at the market, if required, is the responsibility of the buyer.

Cattle destined for slaughter or registered dry feedlots have more flexibility:

• Cattle going directly to a licensed slaughtering establishment are exempt from brucellosis testing requirements upon entry.
• Cattle may be imported into Oregon and consigned to a registered dry feedlot. They may be of any age, vaccinated or not vaccinated, but may not originate from a Designated Area without specific permission from the State Veterinarian before entry.
• On movement from registered dry feedlots, non-vaccinated cattle may move to slaughter or to another registered feedlot only. There are no restrictions on steers and spayed heifers, vaccinated heifers under 18 months old, or eligible vaccinated cattle.

A special exception exists for cattle of proven genetic value. Brucellosis non-vaccinated female cattle of proven genetic advantage for purposes of preserving or developing breeding improvements may be admitted on a case-by-case basis with specific approval of, and under conditions deemed appropriate by, the State Veterinarian. Breed registration papers or other documentation of improved genetics may be required for approval.

Exporting Cattle From Oregon

When you move Oregon cattle to another state, you must comply with the destination state’s import rules, not just Oregon’s. Because Oregon is a Class Free state, your animals benefit from fewer baseline restrictions, but destination states — particularly those near the Greater Yellowstone Area — may impose their own testing or vaccination requirements.

Before sending mature vaccinated cattle interstate, check with the state of destination to determine their policy on mature vaccinates. This is especially important because USDA does not recognize Oregon’s mature vaccination as official vaccination, meaning those animals may face additional scrutiny at the border.

For a comparison of how other states regulate cross-border livestock movement in the context of brucellosis, the guides on brucellosis laws in Michigan, brucellosis laws in Minnesota, and brucellosis laws in Missouri provide useful context.

Reporting and Quarantine Requirements in Oregon

Oregon law places mandatory reporting obligations on veterinarians and imposes strict quarantine procedures when brucellosis is detected or suspected. These rules are found primarily in ORS Chapter 596 and in Oregon Administrative Rules Chapter 603.

Mandatory Reporting

Any person practicing veterinary medicine in Oregon, having knowledge of the existence of any livestock disease listed pursuant to the reporting rules, shall immediately report the disease to the department in the manner provided by rule or regulation. Brucellosis is explicitly listed as a reportable disease under Oregon law.

Cattle brucellosis is a reportable disease in Oregon caused by the bacterium Brucella abortus and mainly infects cattle. If you are a livestock owner and suspect infection in your herd, you are also expected to contact the Oregon Department of Agriculture or your accredited veterinarian immediately. Delayed reporting can compound both the spread of disease and your legal exposure.

Failure to report brucellosis is not just a regulatory misstep — under ORS 686, failure to report or the negligent handling of serious epidemic diseases of animals, including brucellosis, is grounds for professional discipline of a licensed veterinarian.

Quarantine Procedures

When a herd tests positive, Oregon’s quarantine rules under OAR 603-011-0560 activate immediately. A dairy herd shall be quarantined to the premises on which the herd was located at the time of the test, and a beef herd shall be quarantined to the area in which the herd was located at the time of the test. The quarantine shall be issued by an official veterinarian, or other person authorized by the Department, at the time the test results are delivered to the owner.

Reactor animals shall be branded and tagged by the official veterinarian or other persons authorized by the Department. No animal from a herd quarantined for brucellosis may be removed from such quarantined herd without the prior written approval of the Department.

The Oregon Department of Agriculture also has broad authority to issue summary quarantines for animals imported in violation of federal or origin-state rules. The State Department of Agriculture may order summary quarantine of any livestock and any property contaminated with disease or capable of transmitting the disease to other livestock or humans, which have been imported into this state from any area under quarantine by the USDA or by the state or territory of origin, if such livestock or property was removed from such area in violation of applicable rules.

Oregon’s livestock disease regulations connect to broader animal law requirements in the state. If you manage multiple species or facilities, it is worth reviewing related regulations such as beekeeping laws in Oregon and kennel zoning laws in Oregon to ensure full compliance across your operation.

Penalties for Brucellosis Violations in Oregon

Oregon uses a tiered penalty structure for brucellosis-related violations, with consequences ranging from civil fines to criminal classification depending on the nature of the offense. Penalties are codified primarily under ORS 596.990.

Class A Violations

Violation of provisions including ORS 596.321 (rules governing vaccinations and reporting of listed livestock diseases), ORS 596.331(1) (prohibition against disposing of diseased livestock), ORS 596.351 (prohibited acts relating to livestock importation), ORS 596.388 (department’s duty to investigate disease cases), ORS 596.460 (duty to separate and confine diseased animals), or any lawful order of the State Department of Agriculture issued pursuant to this chapter, is a Class A violation.

A Class A violation in Oregon is an unclassified offense carrying a maximum fine set by the court. These are civil infractions — not criminal charges — but they still appear in enforcement records and can affect your standing with the Oregon Department of Agriculture.

Quarantine Violation Fines

Violation of any of the quarantine provisions — including ORS 596.331(2) (prohibition against disposing of parts of quarantined livestock), ORS 596.355 (prohibition against importation of livestock from a quarantined area), ORS 596.392(4) or (5), or ORS 596.394 to 596.402 (summary quarantine authority) — is a specific fine violation punishable by a fine of not more than $5,000.

This means that moving a quarantined animal without written Department approval is not just a paperwork issue — it carries a penalty of up to $5,000 per violation.

Loss of Indemnity Eligibility

One of the most financially significant consequences of a brucellosis violation in Oregon is the loss of indemnity rights. If the state or federal government orders the destruction of your livestock due to disease, you would normally be eligible for compensation. However, Oregon law disqualifies owners from indemnity in several violation scenarios:

• Livestock owned by a person who sold or disposed of diseased animals in violation of reporting rules
• Livestock that were imported in violation of movement permits
• Female cattle that have not been officially vaccinated for brucellosis as required by applicable law.
• Any transaction involving unlawful disposal of diseased livestock disqualifies the owner from receiving indemnity for all livestock owned by that person for which indemnity would otherwise be payable.

Veterinary Licensing Consequences

For accredited veterinarians, the stakes are even higher. Failure to report or the negligent handling of serious epidemic diseases of animals, including brucellosis, is a recognized ground for disciplinary action by the Oregon State Veterinary Medical Examining Board. This can include suspension or revocation of a veterinary license.

Understanding Oregon’s brucellosis penalty structure helps you appreciate why compliance matters well beyond avoiding a fine. The combined risk of quarantine, loss of indemnity, and potential licensing consequences creates strong incentives to follow reporting, vaccination, and movement rules precisely. For questions specific to your operation, contact the Oregon Department of Agriculture’s Animal Health division or your accredited veterinarian.

If you are navigating other animal law questions in Oregon beyond livestock disease, resources on dog bite laws in Oregon, dog leash laws in Oregon, and outdoor cat laws in Oregon cover the state’s broader animal regulatory framework.