TB Statuses that may be Applied to Cattle Herds

OTF

OTF means Officially Tuberculosis Free and is the legal definition used to describe those cattle herds that have no herd restrictions for disease reasons or overdue herd tests, and are free to trade normally, except for any animal that may have individual TB restrictions.  A herd is OTF if:

• all animals undergo a TB test with negative results annually, and,
• there are no clinical signs or suspicion of TB infection in the herd.

OTS

OTS means Officially Tuberculosis free status Suspended. The main reasons for OTS are:

• there is a total of 1 reactor or 1-5 unconfirmed *LRS (Lesion at Routine Slaughter) animals during the course of the breakdown, and no animal has had 2 positive results from the four possible tests: skin, post-mortem, histology, and bacteriology. *LRS is the term used to describe the presence of TB-like lesions found during routine abattoir examination. See the section on Lesions at Routine Slaughter for more information.

  or

• there is one or more animals with an IC (inconclusive) result at an OTF skin test.

  or

• an animal from your herd has been found to be a reactor/LRS in another herd and your herd has been set a Backward Check Test (BCT).

  or

• testing is overdue (see Overdue TB Tests section).

OTW

OTW means Officially Tuberculosis free status Withdrawn. The main reasons for OTW are:

• there is a total of more than 1 reactor or more than 5 unconfirmed LRSs during the course of a TB breakdown, or
• any animal has had 2 positive results from the four possible tests (skin, post-mortem, histology, and bacteriology), or
• any animal has had a bacteriology positive result for M. Bovis, or
• an animal shows clinical signs of TB, or
• an animal from your herd has been found to be a reactor/LRS in another herd and your herd has been set an RHT or RH1 herd test, or
• testing is overdue (see Overdue TB Tests section).