Bovine Tuberculosis Testing Requirements in Wyoming: What Every Cattle Producer Must Know

Bovine tuberculosis testing requirements in Wyoming exist because a single undetected reactor animal can jeopardize the disease-free status that the entire state’s cattle industry depends on. Wyoming ranchers, dairy operators, and anyone moving cattle or bison across state lines need to understand exactly which animals require testing, which methods are approved, and what happens the moment a suspect result appears on a test chart.

This guide walks through the federal and state rules that govern bovine TB testing in Wyoming, from classification status and testing methods to quarantine procedures and the penalties that follow non-compliance. Whether you run a commercial cow-calf operation, a dairy, or import breeding stock from another state, these requirements affect how you manage your herd and your paperwork.

What Is Bovine Tuberculosis and Why It Is Regulated in Wyoming

Bovine tuberculosis is a contagious, zoonotic disease caused by the bacterium Mycobacterium bovis. Bovine tuberculosis is a contagious, infectious, communicable disease of animals and humans caused by Mycobacterium bovis, commonly a chronic, debilitating disease that occasionally becomes acute and rapidly progressive. The disease spreads through several routes, and it is spread by direct contact, inhalation of droplets expelled from infected lungs, and ingestion of contaminated feed or milk.

Most infected cattle show no outward symptoms, which is exactly why testing matters so much. Infected cattle are typically asymptomatic, and detection usually occurs during live animal skin testing or, more commonly, at slaughter through the national slaughter surveillance program. Federal oversight of this disease dates back more than a century: in 1917, the U.S. Bureau of Animal Industry began the National Tuberculosis Eradication Program due to human and livestock concerns regarding bovine tuberculosis.

The program has been remarkably effective, though not perfect. The prevalence of tuberculosis in cattle, bison, and captive cervids is extremely low in the United States, with an estimated prevalence of 7 per 1 million cattle screened. Because the disease can jump to humans, bovine TB is transmissible to humans, though it accounts for less than 2% of tuberculosis cases in the United States. That zoonotic link is a big part of why testing rules stay strict even in states with no recent cases. For a broader look at how this disease compares to other livestock illnesses, see this overview of common bovine diseases.

Wyoming’s TB Classification Status and Risk Zones

Wyoming holds accredited-free status under federal regulation, the highest classification a state can achieve for bovine TB. The accredited-free States listed under federal rule include Alabama, Alaska, Arizona and dozens of others through Wyoming and Wisconsin. To earn and keep that designation, a state must meet a strict bar: a State or zone must have the authority to enforce and comply with the “Uniform Methods and Rules—Bovine Tuberculosis Eradication,” have zero percent prevalence of affected cattle and bison herds, and have had no findings of tuberculosis in any cattle or bison herds in the State or zone for the previous 5 years.

Wyoming does not currently operate under any split-status zones. There are no modified accredited zones designated within the state. That means the entire state carries the same classification, unlike a handful of states that manage separate risk zones internally.

Pro Tip: Accredited-free status is not permanent. It must be renewed annually, and a state must submit certification to APHIS each year confirming compliance with the eradication rules.

Accredited-free State or zone status must be renewed annually, and to qualify for renewal, a state must submit an annual report to APHIS certifying that the state or zone complies with the provisions of the Uniform Methods and Rules. Losing that status has real consequences: if two or more affected herds are detected in an accredited-free State or zone within a 48-month period, the State or zone will be removed from the list of accredited-free States or zones and will be reclassified as modified accredited advanced. A single affected herd doesn’t automatically trigger that downgrade, though. If an affected herd is detected in a State or zone classified as accredited-free, and the herd is depopulated and an epidemiologic investigation is completed within 90 days with no evidence of the spread of tuberculosis, the State or zone may retain its accredited-free status.

Historically, Wyoming’s testing numbers have stayed clean. State records from a 2005 annual report show Wyoming cattle producers tested 2,555 head of livestock with no TB found in Wyoming animals, and Wyoming continued to maintain its TB-free status. While that figure is dated, it illustrates the ongoing surveillance effort behind the state’s current classification.

Who Must Test and Which Animals Are Covered in Wyoming

Wyoming statute targets specific categories of cattle for mandatory TB testing, with dairy operations facing the most direct requirement. All cows in Wyoming supplying milk or cream in cities or towns or to creameries in the state, and all bulls exposed or known to have been exposed to such cows, must be tested for tuberculosis. This rule has stayed on the books for decades and remains the backbone of Wyoming’s dairy-sector TB surveillance.

For herd accreditation and reaccreditation purposes, the age of test-eligible animals depends on the state’s classification. Because Wyoming is accredited-free, the standard is higher than in lower-status states: in Accredited Free States or zones, all cattle or bison 24 months of age and older, as evidenced by loss of the central deciduous incisors, must be included in herd testing. Compare that to lower-status classifications, where the age threshold drops — 18 months in Modified Accredited Advanced areas, and 12 months in Modified Accredited areas.

Enforcement authority runs through the Wyoming State Veterinarian’s office, which can deputize additional staff when needed. The state veterinarian, with the consent of the governor, may appoint a qualified person as special deputy state veterinarian to act under the direction of the state veterinarian, and that deputy must take an oath and post a bond of three thousand dollars to the state.

Wyoming law also gives county residents a mechanism to trigger broader testing. Whenever sixty percent or more of the taxpayers of any county, as shown by the last assessment roll, petition the board of county commissioners asking that cattle within the county be tested for tuberculosis, the board must notify the state veterinarian, who then proceeds with testing in accordance with federal rules for establishing and maintaining tuberculosis modified accredited areas. This gives local communities a formal path to request enhanced surveillance if they have concerns about herd health in their area.

Testing isn’t limited to cattle and bison, either. Testing of any species other than cattle or bison requires special training for the accredited veterinarian performing it, which matters for anyone running captive cervids or other susceptible species alongside a cattle operation. If you also manage horses or other livestock crossing state lines, review the related EIA/Coggins test requirements in Wyoming for equine-specific testing rules.

Approved TB Testing Methods in Wyoming

The primary screening tool used in Wyoming is the caudal fold test, a skin test performed by accredited veterinarians who have completed additional certification through the Wyoming Livestock Board. In addition to state and federal accreditation, accredited veterinarians must be certified by the WLSB for disease programs including tuberculosis testing prior to performing official testing, and producers should contact the Wyoming Livestock Board for certification session information.

The technique itself follows a precise protocol laid out in the state’s veterinary accreditation handbook:

• Use a 3/8-inch, 26-gauge needle with a half-cc or 1cc disposable syringe, drawing in one dose of 0.1cc of USDA contract bovine PPD tuberculin at a time.
• Clean the caudal fold with cotton before injection.
• Insert the full length of the needle between the superficial layers of the skin, intradermally, withdraw slightly, and inject — a proper injection will raise a small bleb at the injection site.
• Read the test at 72 hours, plus or minus 6 hours, by palpation and observation.

Only officially licensed tuberculin can be used for this work. Official testing must use only bovine purified protein derivative tuberculin (PPD bovis) licensed by USDA. Test conditions matter too — the animal being tested should not concurrently be receiving other medications, vaccinations, or anthelminthic drugs, because these agents may temporarily affect the immune system and influence the tuberculin test result.

Key Insight: A caudal fold test result is only a screening tool. Any animal that responds must go through additional evaluation before a final classification is made.

When a test produces a response, the reading itself must be hands-on. Test observation without palpation is unacceptable. Results are recorded using standardized codes — a veterinarian enters “N” for negative when no change in tissue is observed at the injection site, or “S” for suspect when an increase in caudal fold thickness, size, or sensitivity is observed or palpated. Animals that respond move to the next diagnostic stage: 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.

Interstate and Intrastate Movement Testing Requirements in Wyoming

Because Wyoming carries accredited-free status, cattle leaving the state generally move with minimal TB-related paperwork. Cattle or bison that originate in an accredited-free State or zone may be moved interstate without further restriction under the federal tuberculosis regulations. That reciprocity works both ways among free states — as one animal health agency put it after recognizing Wyoming’s status, this recognition allows producers to buy and import beef cattle and bison from these states with reduced vaccination and testing requirements for these two diseases.

Bringing cattle into Wyoming is a different story for certain animals. Wyoming Livestock Board import rules single out sexually intact dairy cattle for extra scrutiny: sexually intact dairy cattle six months of age and over require tuberculosis tests performed within the previous nine months, with the second of these tests occurring within ninety days prior to importation. If timing doesn’t line up perfectly, there’s a fallback option — the Wyoming State Veterinarian has the discretion to allow such cattle to be imported under quarantine and subjected to the second test.

Documentation follows the animal. A complete history of prior tuberculosis testing, including the date, location, and testing veterinarian’s name, must be provided on the International Certificate of Veterinary Inspection. Identification requirements are permanent, too: these animals are required to have a country-of-origin official tag which must not be removed for the life of the animal.

Camelid owners get a lighter touch if their animals come from an already-clean source. Camel Family Species animals of U.S. origin from an Accredited-free or Modified accredited advanced state are not required to be tuberculosis tested. Animals from lower-status origins face a shorter testing window: a tuberculosis test conducted in the axillary region within sixty days prior to importation is required for those animals. An ICVI is required on all Camel Family Species entering Wyoming regardless of TB testing status. If you’re planning to haul cattle or camelids across state lines, pair this with the livestock trailer requirements in Wyoming and confirm your brand inspection requirements in Wyoming are current before you load animals for transport.

What Happens When a Suspect or Positive Result Occurs in Wyoming

Speed matters once a test comes back suspect. Suspects must be reported by telephone, on the day of observation, to the Veterinary Medical Officer in that section, including weekends and after hours. Accredited veterinarians carry a parallel reporting obligation under federal rule: 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.

Owners have an obligation the moment disease is suspected, before any official even arrives. The owner or person having charge of any animal affected with or suspected of any contagious or infectious disease shall immediately confine the animal in a safe place, isolated from other animals, with all necessary restrictions to prevent dissemination of the disease until the arrival of the state veterinarian.

From there, the confirmatory testing process kicks in. When slaughter and marketing records provide strong evidence tracing back to the herd of origin, all animals responding to the caudal fold test shall be classified as reactors; otherwise, with approval of the designated tuberculosis epidemiologist, the comparative cervical test and/or bovine interferon gamma assay may be used to classify responders to the caudal fold test. Regulatory veterinarians handle this confirmatory work directly: testing of source herds of reactors disclosed in affected herds is done by State or Federal regulatory veterinarians using the CFT test procedure, and responding animals may be classified as reactors or, if classified as suspects, retested by the comparative cervical test or gamma interferon assay.

Quarantine and Herd Depopulation Rules in Wyoming

Once TB is confirmed, quarantine follows automatically for the affected herd and any exposed animals. Federal rule reinforces this at the herd level, and Wyoming rule extends surveillance well beyond the index premises: all livestock herds within a 10-mile radius will be tested within 6 months of any diagnosis of bovine tuberculosis.

Disposal of confirmed reactor animals follows a defined legal pathway rather than being left to individual discretion. All livestock in Wyoming lawfully found to be affected with tuberculosis may be shipped or transported, under the direction of the state veterinarian and in accordance with federal regulations, to livestock markets and there sold for salvage and destroyed, or transferred to an approved slaughter facility or veterinary diagnostic laboratory.

Important Note: Owners of condemned livestock are not simply left to absorb the full financial loss. State law requires funding verification before any forced sale proceeds.

Prior to directing that any affected livestock be sold under this section, the state veterinarian shall ascertain that sufficient funds are available from either federal or state sources to ensure that the owner of condemned livestock will be paid the difference between the market value at the time of quarantine and the amount received for the sale, less any amount of reimbursement provided for and paid under federal law or regulation, the cost of shipping or transportation, and commission charges. This indemnification structure is designed to soften the financial blow of depopulation while still removing infected animals from the herd promptly.

For animals held for salvage feeding rather than immediate slaughter, federal rule defines a quarantined feedlot as a confined area under the direct supervision and control of a State livestock official, maintained for finish feeding of livestock in drylot with no provision for pasturing and grazing. Movement out of that facility is one-way: all livestock leaving such a feedlot must only move directly to slaughter in accordance with established procedures for handling quarantined livestock.

This entire quarantine-and-depopulation framework exists to protect Wyoming’s accredited-free status without wiping out an entire regional cattle economy over one infected herd, which is why the 90-day epidemiologic investigation window discussed earlier carries so much weight for producers near an affected premises. If you raise other livestock species alongside cattle, the avian tuberculosis overview covers how the mycobacterial disease family behaves differently in poultry and captive birds.

Penalties for Non-Compliance in Wyoming

Wyoming treats violations of its livestock import and disease-control rules as serious matters with layered consequences rather than a simple fine schedule. Under the state’s current import rules, pursuant to Wyoming Statute §§ 11-19-111 and 11-1-103, violations of these rules may result in criminal charges, quarantine of animals, seizure of animals, and civil liability for damages caused by a violation.

The underlying statute gives the governor and the Wyoming Livestock Board broad authority to regulate livestock movement in the first place. The governor, upon recommendation of the Wyoming Livestock Board, may regulate by proclamation the importation into Wyoming from any other state of any livestock, or any virulent blood or live virus of any disease affecting livestock, or any related item, as outlined in the statute’s provisions on prohibited acts, penalties, and applicability.

General agency rules echo this same enforcement philosophy across the board. Penalties for a violation of these rules shall be pursuant to law, meaning enforcement draws on the full weight of Wyoming’s civil and criminal statutes rather than a single capped penalty. In practical terms, a producer who ignores a quarantine order, falsifies a test history on an import certificate, or moves untested cattle in violation of Chapter 8 import rules can face financial liability, animal seizure, and potential criminal prosecution simultaneously.

Pro Tip: Keep copies of every TB test result and ICVI for at least the retention period your accredited veterinarian recommends. Documentation is your first line of defense if a compliance question ever comes up at a port of entry or brand inspection.

Because these penalties tie back to broader animal-health statutes, producers moving cattle regularly benefit from staying current on adjacent compliance areas as well, including rabies vaccine requirements in Wyoming for other species on the operation and hunting license requirements in Wyoming if wildlife management near cattle grazing areas is part of your broader herd health strategy. Bovine tuberculosis testing requirements in Wyoming are not likely to loosen anytime soon, given how much of the state’s cattle economy depends on maintaining its accredited-free classification.