T.B. Testing Of Herds

Press, Volume CX, Issue 32349, 15 July 1970, Page 16

T.B. Testing Of Herds

Sir,—Recent statements about T.B. eradication avoid the main issue: failure of the caudal fold test to detect carrier animals. As long as these animals are left in the herds all efforts to eradicate T.B. in dairy cattle will be in vain. Compulsory testing has been carried out for seven years and it still frequently happens that animals passing the caudal fold test for years are condemned at the works with T.B. Compensation for reactors at $6B an animal is inadequate and neither loss of production nor transport costs are paid. To expect farmers to carry this useless scheme any longer is unfair and unnecessary.—Yours, etc., < P. VAN VUGT.

Inangahua, July 7, 1970. [Mr M. C. Armstrong, district field veterinary officer of the Department of Agriculture, replies: “For the detection of T.B. in cattle New Zealand uses the intradermal T.B. test using mammalian tuberculin. This test is used in many countries throughout the world, especially in those with advanced progress in technology and science. In the larger cattle-raising countries such as Canada, the United States, Australia, and New Zealand, the caudal fold site on the tail has proved to be the most satisfactory and convenient. The intradermal T.B test has proved to be at least 98 per cent efficient in detecting T.B. infection. Long-stand-ing cases of T.B. infection occasionally lose sensitivity to tuberculin. This animal is usually culled out because of age or because of retarded production. Competent and discriminating cattlemen