Different tests (and combinations thereof) can be used to diagnose or rule out the same disease, depending on the circumstances and background risk of infection in a particular country or group of animals. In the case of TB in alpacas and llamas, and in the absence until recently of a better alternative, the comparative intradermal tuberculin test ("skin test") has traditionally been used to screen camelids for TB infection in most countries.

However, it is acknowledged that the skin test has a low sensitivity in camelids, it is cumbersome and difficult to standardise under field conditions and, consequently, it fails to detect many infected animals in a herd. As a result, to increase the sensitivity of the TB testing regime in known infected camelid herds, AHVLA has deployed since 2006 a supplementary blood test (the Chembio StatPak). This test is offered to camelid keepers on a voluntary basis in conjunction with the skin test. AHVLA, with the financial support of the British camelid industry, has recently validated this and other blood tests for TB in alpacas, the results of which have been peer reviewed and published.

I refer my hon. Friend to the answer given in response to the same question asked on 13 June 2012, Official Report, column 490W.