Bovine Tuberculosis Testing Requirements in South Carolina: Rules Every Cattle Producer Should Know
August 11, 2026
If you move cattle or bison across South Carolina’s borders, a single overlooked test requirement can mean a rejected shipment, a quarantine order, or a lost sale. Bovine tuberculosis testing requirements in South Carolina are shaped by both federal disease-status rules and state enforcement through Clemson University’s Livestock Poultry Health division, and the two systems interact in ways that trip up even experienced producers.
This guide walks through what the disease is, how South Carolina is classified, which animals and owners are affected, and what happens when a test comes back anything other than clean. You will also find the movement rules that apply whether you are shipping cattle out of state or bringing new stock onto your farm.
What Is Bovine Tuberculosis and Why It Is Regulated in South Carolina
Bovine tuberculosis is caused by Mycobacterium bovis, a bacterium that produces a chronic, sometimes debilitating disease in cattle and a wide range of other mammals. Bovine tuberculosis (TB) is a contagious, infectious, communicable disease of animals and humans caused by Mycobacterium bovis, and it is commonly a chronic, debilitating disease but occasionally may assume an acute, rapidly progressive course. It is a widespread zoonosis of global magnitude that affects nearly all species of vertebrates, and it spreads through direct contact, inhalation of droplets expelled from infected lungs, and ingestion of contaminated feed or milk.
Because the disease can pass from cattle to people, and because infected animals rarely show outward symptoms, regulators treat it as a slaughter and trade issue as much as a herd-health issue. 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. APHIS and state animal health agencies collaborate with U.S. livestock producers to administer the National Tuberculosis Eradication Program, which has nearly eradicated tuberculosis from the nation’s livestock population since its inception in 1917.
South Carolina’s rules exist within that cooperative federal-state framework. For a broader look at how the state manages disease risk across species, see this overview of livestock biosecurity requirements in South Carolina.
South Carolina’s TB Classification Status and Risk Zones
Every state receives a federal tuberculosis classification that determines how strict its testing rules must be, and South Carolina currently holds a favorable status for cattle and bison. Federal regulation lists South Carolina among the accredited-free states for bovine tuberculosis, alongside most other states in the country. That classification matters directly to producers because of what it unlocks for movement. Cattle or bison that originate in an accredited-free State or zone may be moved interstate without further restriction under the federal tuberculosis rule. To earn and keep that status, the state has to meet a strict definition. An accredited-free state or zone is one that has the authority to enforce and complies with the Uniform Methods and Rules for Bovine Tuberculosis Eradication, has zero percent prevalence of affected captive cervid herds, and has had no findings of tuberculosis in any captive cervid herds for the previous five years.
That free status is not permanent by default. 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 compliance with the Uniform Methods and Rules, submitted each year between October 1 and November 30. If an infected herd turns up, the state does not automatically lose its status. If an affected herd is detected in a state classified as accredited-free and it is depopulated with an epidemiologic investigation completed within 90 days showing no evidence of spread, the state can retain its classification; failure to meet these steps risks reclassification.
Key Insight: South Carolina’s cattle and bison herds carry accredited-free status, but the state’s captive cervid population (deer, elk, and similar species raised commercially) sits under a separate, more restrictive “modified accredited” classification. If you raise both cattle and cervids, check the rules for each species independently rather than assuming one status covers your whole operation.
Because that dual classification exists, risk zones in South Carolina are effectively defined by species rather than geography. Cattle and bison producers benefit from the state’s clean disease history, while cervid operations face closer federal scrutiny under the same underlying regulation, found at 9 CFR Part 77.
Who Must Test and Which Animals Are Covered in South Carolina
Testing obligations in South Carolina fall on anyone who owns, moves, or imports cattle, bison, or captive cervids, whether the operation is a commercial dairy, a small cow-calf herd, or a single rodeo bull. The federal Uniform Methods and Rules set the baseline age at which animals become “test eligible,” and that age shifts depending on a state’s classification.
| State/Zone Classification | Cattle or Bison Age Requiring Testing |
|---|---|
| Accredited-Free (South Carolina’s current cattle/bison status) | 24 months and older |
| Modified Accredited Advanced | 18 months and older |
| Modified Accredited | 12 months and older |
| Accreditation Preparatory | All ages |
In accredited-free states or zones, testing applies to all cattle or bison 24 months of age and older; in modified accredited advanced zones the threshold drops to 18 months; in modified accredited zones it drops further to 12 months; and in accreditation preparatory zones, all cattle and bison regardless of age must be tested. Because South Carolina’s cattle and bison hold accredited-free status, most routine testing inside the state applies only to older, test-eligible animals rather than the entire herd.
Identification matters just as much as age. Every animal presented for an official test needs to carry official identification that ties the test record to that specific animal, which is why the state’s livestock ear tag requirements in South Carolina work hand in hand with TB testing paperwork. Owners of accredited herds also carry ongoing obligations: to establish or maintain accredited herd status, the herd owner must comply with all provisions of the Uniform Methods and Rules regarding accredited herds, and all cattle and bison in the herd must be free from tuberculosis.
Approved TB Testing Methods in South Carolina
South Carolina veterinarians rely on the same federally approved test menu used nationwide. There are three official TB tests for cattle and bison — the caudal fold test (CFT), the cervical test (CT), and the comparative cervical test (CCT) — and the Interferon Gamma Assay, known as Bovigam, is an additional official test for cattle only. Each serves a different stage of the testing pathway.
- Caudal fold test (CFT): The frontline screening test, performed by injecting tuberculin into the tail fold. 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.
- Comparative cervical test (CCT): A confirmatory skin test used on animals that respond to the CFT, comparing reactions to both bovine and avian tuberculin to rule out cross-reactions.
- Gamma interferon assay (Bovigam): A blood-based test that measures immune response rather than skin swelling, often used to speed up confirmation without waiting on a second skin-test cycle.
Test administration follows strict protocol regardless of which method is used. Only bovine purified protein derivative tuberculin, licensed by USDA, may be used for official testing. Reading the result requires more than a glance: test observation without palpation is unacceptable, and a positive response, if it occurs, usually begins within 8 to 12 hours and peaks about 72 hours after injection.
False positives are a known limitation of skin testing. These false-positive responses may occur in 1 to 5 percent of tested cattle, and a positive caudal fold test is only a preliminary result — the animal requires additional diagnostic testing before any conclusion is drawn. That is why a single reactor rarely triggers immediate destruction; it triggers a confirmatory testing sequence instead. This layered approach mirrors how South Carolina handles other mandatory animal health screenings, including the EIA Coggins test requirements in South Carolina used for equine infectious anemia.
Interstate and Intrastate Movement Testing Requirements in South Carolina
Movement rules are where South Carolina’s accredited-free status pays off most directly for producers. According to Clemson Livestock Poultry Health’s cattle and bison import guidance, tuberculosis testing is not required for farm-to-farm movement from another free state, but animals coming from any other classification must be tested within 30 days prior to entry. The same 30-day testing window applies to brucellosis under the same import rule. Brucellosis testing follows an identical structure — no test required from a free state on a farm-to-farm shipment, and a 30-day pre-entry test required from all other origins.
Certified accredited herds get a documentation shortcut rather than a testing exemption. Owners of certified accredited herds put the herd number and date of last test on the Certificate of Veterinary Inspection rather than arranging a fresh individual test for each animal moved.
Pro Tip: Before you buy or transport cattle across state lines, confirm the seller’s state TB classification, not just South Carolina’s. If the animal originates from a modified accredited or lower-status state or zone, budget extra time for the mandatory 30-day pre-entry test and make sure the Certificate of Veterinary Inspection lists official identification for every animal.
Every animal entering South Carolina from out of state needs a Certificate of Veterinary Inspection regardless of TB status. Moving livestock into South Carolina from another state requires a CVI issued by an accredited veterinarian. For the full species-by-species breakdown, Clemson’s cattle and bison import requirements page is the authoritative source producers should check before any shipment.
Intrastate movement within South Carolina carries fewer hurdles because the whole state shares one classification, but herd owners moving animals to shows, sales, or new pastures should still keep test records and official identification current. If you also manage horses on the same operation, the state applies a comparable philosophy to equine disease control — see the rabies vaccine requirements in South Carolina for how vaccination and documentation rules extend across species.
What Happens When a Suspect or Positive Result Occurs in South Carolina
A “suspect” result does not mean a confirmed infection, but it does trigger a mandatory chain of reporting and follow-up testing. If a tuberculin test produces any type of response, the veterinarian must immediately notify the APHIS Veterinary Services Area Office and state animal health officials. Accredited veterinarians carry a personal reporting duty on top of that: 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.
From there, the animal moves into a confirmatory testing track. As covered in the testing methods section above, a suspect CFT result leads to a comparative cervical test, a gamma interferon assay, or direct movement to slaughter under permit rather than an automatic reactor designation. Regulatory veterinarians manage this step, and owners typically cannot make that call independently.
Because tuberculosis has no approved treatment in livestock, the options narrow quickly once a reactor is confirmed. Tuberculosis is not treated in livestock, and producers or owners who suspect an animal disease should contact their veterinarian to evaluate the animal or herd. Owners also take on a duty to protect the people around the herd. Owners of infected or exposed cattle and bison must be advised of the possible danger these animals present to themselves, their families, their employees, and the general public, and all persons with possible exposure should be advised to seek medical attention.
Quarantine and Herd Depopulation Rules in South Carolina
Once a herd is confirmed affected, the disease-control response follows a set sequence: quarantine, testing of exposed animals, and — in most cases — removal of reactors or full depopulation. All livestock herds within a 10-mile radius will be tested within six months of any diagnosis of bovine tuberculosis, which shows how far the response radius extends beyond the affected premises itself.
Depopulation timing directly affects how quickly a herd, or the state as a whole, can regain a clean classification. The requirement of freedom from tuberculosis in herds is two years from depopulation of the last affected herd in states or zones that were previously accredited free, and three years in other states that have depopulated all affected herds. That timeline is a major reason state animal health officials move quickly on confirmed cases rather than allowing a prolonged quarantine.
Milk handling rules apply immediately upon quarantine, even before depopulation is complete. All milk from affected herds must be pasteurized prior to human or animal consumption, milk from TB reactors must not be used for human or animal consumption at all, and owners of reactors must segregate tuberculin reactors from non-reactors and dispose of their milk in a safe manner.
Important Note: Depopulation and indemnity decisions in confirmed bovine TB cases involve both state and federal animal health officials, and specific compensation or disposal terms can vary by case. Producers facing a quarantine order should work directly with Clemson Livestock Poultry Health and their accredited veterinarian rather than relying on general guidance for case-specific decisions.
New herds assembled on a depopulated premises face their own testing rules before they can be considered TB-free. If any livestock other than captive cervids are included in a newly assembled herd on a premises where a tuberculous herd has been depopulated, the state must apply the herd test requirements contained in the Uniform Methods and Rules to those other livestock in the same manner as to cattle and bison. Clemson’s Animal Health Programs division, reachable through the beef cattle information page, coordinates these follow-up requirements at the state level.
Penalties for Non-Compliance in South Carolina
South Carolina’s authority to require testing, restrict movement, and quarantine or destroy animals rests on state statute, not just federal courtesy. State laws and regulations must be in place to provide the authority to apply tuberculosis tests to any livestock and to restrict the movement of any livestock or other animals, including captive wildlife suspected of being affected. In South Carolina, that authority is written into the Clemson University State Livestock-Poultry Health Commission regulations. Livestock biosecurity law in South Carolina, including disease-testing enforcement, is administered primarily by Clemson Livestock-Poultry Health under the authority of SC Code Title 47 and associated regulations.
The regulatory chapter governing this authority draws its power directly from state code. The Clemson University State Livestock-Poultry Health Commission regulations cite statutory authority under 1976 Code Sections 47-4-30 and 47-17-130, among others. Those provisions back up the state veterinarian’s power to issue quarantine orders, deny movement documents, and require testing before entry or sale.
- Movement without a valid CVI or required test: Shipments can be held, rejected at destination, or subjected to retroactive testing before release.
- Failure to report a suspect result: Accredited veterinarians who skip mandatory reporting risk losing their federal accreditation status, separate from any state penalty.
- Non-compliance with quarantine terms: State animal health officials can extend, expand, or escalate a quarantine order, and non-compliant premises risk broader movement restrictions affecting neighboring herds.
Because specific fine amounts and administrative procedures can be updated between publication cycles, producers should confirm current enforcement details directly with Clemson LPH rather than relying solely on secondary sources. The full text of the state’s governing framework is available through the South Carolina Code of Regulations, Chapter 27, which covers the Clemson University State Livestock-Poultry Health Commission in detail.
Pro Tip: Keep every CVI, test record, and official identification document for at least a full calendar year. If a compliance question comes up after a sale or show, having your own paperwork on hand resolves disputes far faster than requesting records back from a buyer or hauler.
Bovine tuberculosis testing in South Carolina hinges on one central fact: the state’s accredited-free status for cattle and bison keeps routine testing burdens light for in-state and farm-to-farm movement, but that status depends on strict federal compliance and fast action whenever a suspect animal turns up. Producers who track their animals’ official identification, confirm the TB classification of any out-of-state seller, and keep current documentation on hand avoid the vast majority of compliance problems before they start. When in doubt about a specific herd, shipment, or test result, Clemson Livestock Poultry Health and your accredited veterinarian remain the two most reliable sources for a current, case-specific answer.