SECTION 43.21. General Requirements

(a) Reporting of tests. All cervidae tested shall be officially identified at the time of an official test. A report of all tuberculosis tests, including the official identification of each animal, a record of the size of the response of the Single Cervical Tuberculin Test or the result of the TB Cervid Stat Pak Antibody Testing where indicated, and test interpretation shall be submitted in accordance with the requirements of the cooperating state and federal officials.

(b) Classification of cervidae tested.

(1) Single cervical tuberculin test.

(A) Herds of unknown status. All SCT responses shall be recorded and the animals classified as suspects and quarantined for retest with the CCT, unless in the judgment of the testing veterinarian the reactor classification is indicated.

(B) Known infected herds. All responses shall be recorded and the animals classified as reactors.

(2) Comparative cervical test--All responses are to be measured to the nearest 0.5mm.

(A) Animals having a response to bovine PPD of less than 1mm should be classified negative.

(B) Animals having a response to bovine PPD from 1mm through 2mm that is equal to or greater than the avian PPD response shall be classified as suspects.

(C) Animals having a response to bovine PPD greater than 2.0mm but equal to the avian response shall be classified as suspects, except when in the judgment of the testing veterinarian the reactor classification is indicated.

(D) Animals meeting the criteria for suspect classification on two successive CCTs shall be classified as reactors.

(E) Animals having a response to bovine PPD which is greater than 2.0mm and is 0.5mm greater than the avian PPD response shall be classified as reactors.

(3) Suspect SCT cervids may be retested by the CCT only. The CCT may be applied within ten days following the SCT injection or after 90 days. If the CCT is applied within ten days of the SCT, the opposite side of the neck shall be used. Animals positive to the CCT shall be classified as reactors.

(4) Suspects may be necropsied in lieu of retesting, and, if found without evidence of M. bovis infection by histopathology and culture (including selected NGL specimens submitted from animals having no gross lesions indicative of tuberculosis), shall be considered negative for tuberculosis.

(c) Classification of captive elk, red deer, white-tailed deer, fallow deer or reindeer tested.

(1) Cervid TB Stat Pak antibody test.

(A) Herds of unknown status. All Stat Pak non-negative responses shall be recorded and the animals classified as suspects and quarantined for retest with the DPP unless in the judgment of the DTE the reactor classification is indicated.

(B) Known infected herds. All non-negative responses shall be recorded and the animals classified as reactors.

(2) Dual-Path Platform Test shall be performed on all non-negatives samples submitted for Stat Pak Testing. Animals non-negative on the Stat-Pak test and non-negative on a single DPP test should be classified as suspect unless the DTE determines that a reactor classification is warranted.

(3) Animals classified as suspect by a single DPP test may be retested with the DPP test only with a new blood sample drawn no sooner than 30 days after the initial sample was obtained.

(4) Animals that are non-negative on two successive DPP tests should be classified as reactor.

(5) Suspects may be necropsied in lieu of retesting, and, if found without evidence of M. bovis infection by histopathology and culture (including selected NGL specimens submitted from animals having no gross lesions indicative of tuberculosis), shall be considered negative for tuberculosis.

(d) Disposition of Tuberculin-Responding Cervidae.

(1) Reactors shall remain on the premises where they were disclosed until a state or federal permit for movement has been obtained. Movement for immediate slaughter will be within 15 days of classification directly to a slaughter establishment where approved state or federal inspection is maintained. Alternatively, the animals may be destroyed and necropsy conducted by or under the supervision of a state or federal regulatory veterinarian that has been trained in tuberculosis necropsy procedures.

(2) Herds containing suspects to the SCT shall be quarantined until the suspect animals are:

(A) retested by the CCT within ten days of the SCT injection; or

(B) retested by the CCT after 90 days; or

(C) shipped under permit directly to a slaughter facility under state or federal inspection, or necropsied. If such animals are found without evidence of M. bovis infection by histopathology and culture (including selected NGL specimens submitted from animals having no gross lesions indicative of tuberculosis), they shall be considered negative for tuberculosis.

(3) Suspects to the CCT shall remain under quarantine until:

(A) comparative cervical suspects are retested by the CCT after 90 days; or

(B) such animals are shipped under permit directly to a slaughter facility under state or federal inspection, or necropsied. If such animals are found without evidence of M. bovis infection by histopathology and cultured (including selected NGL specimens submitted from animals having no gross lesions indicative of tuberculosis), they shall be considered negative for tuberculosis.

(4) An animal meeting the suspect criteria on two successive CCT tests followed by one suspect CCT test shall be classified as a reactor and be identified as such. The testing veterinarian must justify exceptions in writing and have the concurrence of State or Federal animal health personnel.

(e) Identification of Reactors. Reactor cervids shall be identified by branding with the letter "T" at least two by two inches in size, high on the left hip near the tailhead, and by tagging with an official eartag bearing a serial number and inscription "U.S. Reactor" attached to the left ear of each reactor animal.

(f) Disposition of elk, red deer, white-tailed deer, fallow deer or reindeer that are non-negative on the Stat-Pak test and non-negative on a single DPP test.

(1) Reactors shall remain on the premises where they were disclosed until a state or federal permit for movement has been obtained. Movement for immediate slaughter will be within 15 days of classification directly to a slaughter establishment where approved state or federal inspection is maintained. Alternatively, the animals may be destroyed and necropsy conducted by or under the supervision of a state or federal regulatory veterinarian that has been trained in tuberculosis necropsy procedures.

(2) Herds containing suspects to the Stat-Pak test and a single DPP test shall be quarantined until the suspect animals are:

(A) retested by the DPP test only with a new blood sample drawn no sooner than 30 days after the initial sample was obtained; or

(B) shipped under permit directly to a slaughter facility under state or federal inspection, or necropsied. If such animals are found without evidence of M. bovis infection by histopathology and culture (including selected NGL specimens submitted from animals having no gross lesions indicative of tuberculosis), they shall be considered negative for tuberculosis.

(3) Animals that are non-negative on two successive DPP tests should be classified as reactor. Any exceptions to reactor classification must be justified by the designated TB epidemiologist in writing and have the concurrence of the regional TB epidemiologist.

(g) Quarantine procedures.

(1) All herds in which reactor animals are disclosed shall be quarantined. Exposed animals must remain on the premises where disclosed unless a state or federal permit for movement to slaughter has been obtained. Movement for immediate slaughter must be directly to a slaughter establishment where approved state or federal inspection is administered. Animals must be identified by official eartag. Use of "S" brand is required, or animals must be shipped in an official sealed vehicle. The "S" brand shall be applied to either the left jaw or the tailhead.

(2) Cervidae herds in which M. bovis is confirmed shall remain under quarantine if not depopulated, and must pass three consecutive official tuberculosis tests of all animals. The first test must be conducted 90 days or more after the last test yielding a positive animal, with two additional tests at 180-day minimum intervals. Five annual complete herd tests of all animals shall be given following the release from quarantine.

(3) Cervidae herds that have had a test of all eligible animals with NGL reactors only and no evidence of tuberculosis infection is found by histopathology and culture of M. bovis (including selected NGL specimens submitted from animals having no gross lesions indicative of tuberculosis) may be released without further restrictions.

(4) Cervidae herds in which compatible or suggestive lesions are found by histopathology without the isolation of M. bovis may be released from quarantine following a negative 90-day retest of the entire herd, provided there is no known association with M. bovis.

(5) Cervidae herds that exhibit NGL reactors in which no evidence of tuberculosis infection is found by histopathology and culture of M. bovis and are unable to conduct a test of all eligible animals, shall be evaluated by the state and/or regional tuberculosis epidemiologist for possible release of quarantine.

(h) Procedures in affected herds. Disclosure of tuberculosis in any herd shall be followed by a complete epidemiological investigation. All cervids in herds from which tuberculosis animals originate, and all cervids that are known to have associated with affected cervids or other affected animals, shall be tested promptly. These procedures shall apply to adjacent and contact herds as well as to the evaluation and testing of possible source herds for the affected herd. Herds that have received exposed animals shall be tested following the slaughter or testing of the exposed animals. Every effort shall be made to ensure the immediate elimination of the disease from all species of animals on the premises. The herd shall be handled as outlined under subsection (g) of this section.

(i) Retest Schedules for High Risk Herds.

(1) In herds with a history of lesions compatible or suggestive for tuberculosis by histopathology, two complete annual herd tests shall be given after release from quarantine. Herds with a bacteriologic isolation of a Mycobacteria species other than M. bovis should be considered negative for bovine tuberculosis with no further testing requirements.

(2) In a newly assembled herd on premises where a tuberculosis herd has been depopulated, two annual herd tests shall be applied to all animals. The first test must be approximately six months after assembly of the new herd. If the premises are vacated for over one year, these requirements may be waived.

(3) Exposed animals previously sold from known infected herds shall be depopulated if possible, or tested with the SCT or Stat Pak/DPP by State or Federal veterinarians. All animals non-negative to either test shall be classified as reactors.

(A) If bovine tuberculosis is confirmed in the exposed animal(s), the remainder of the receiving herd shall be classified as an infected herd and handled according to subsection (g)(2) of this section.

(B) If negative to the test, the exposed animal(s) will subsequently be handled as if a part of the infected herd of origin for purposes of testing, quarantine release, and the five annual high-risk tests. The remainder of the herd shall be tested at the time of the initial investigation and retested in one year with the SCT or Stat Pak/DPP. Supplemental diagnostic tests may be used if needed.

(4) Herds indicated as the source(s) of animals in slaughter traceback investigations shall be placed under quarantine within 30 days of notification to the area office, and a herd test scheduled. Testing of source herds of slaughter animals having lesions of tuberculosis shall be done by state or federal regulatory veterinarians using the SCT or Stat Pak/DPP.

(A) If the herd of origin is positively identified and M. bovis has been confirmed by bacterial isolation from the slaughter animal, all animals responding to the SCT or Stat Pak/DPP shall be classified as reactors. In all other cases, supplemental diagnostic tests may be used.

(B) In herds identified as the source of culture negative lesioned animals, responding animals may be classified as reactors or suspects. If classified as suspects, they may be retested by supplemental diagnostic tests.

(j) Cleaning and disinfection of premises, conveyances, and materials. All premises, including all structures, holding facilities, conveyances, and materials that are determined by program officials to constitute a health hazard to humans or animals because of tuberculosis, shall be properly cleaned and disinfected. This shall be done within 15 days after the removal of tuberculosis-affected or exposed cervids in accordance with approved procedures. However, these officials may extend the time limit for disinfection to 30 days when a request for such extension is received prior to the expiration date of the original 15-day period allowed.

Source Note: The provisions of this §43.21 adopted to be effective August 31, 1995, 20 TexReg 5857; amended to be effective July 5, 1996, 21 TexReg 5555; amended to be effective October 1, 1997, 22 TexReg 11346; amended to be effective October 7, 2013, 38 TexReg 6912