TESTING DAIRY HERDS

Wairarapa Times-Age, 19 August 1939, Page 5

TESTING DAIRY HERDS

ERADICATION OF BOVINE TUBERSULOSIS COMPREHENSIVE SCHEMES DIFFICULT. POSSIBILITY OF ACCREDITED HERDS & AREAS. Difficulties which faced the Government in undertaking comprehensive schemes for testing dairy herds in New Zealand for tuberculosis were outlined by the Minister of Agriculture, the Hon. W. Lee Martin, in an interview today. The Minister said that at the present time it did not appear practicable to introduce a Dominion-wide scheme for many reasons, but that if some plan could be devised in which the cost could be spread equitably over the whole industry and taxpayers generally, the Government would be-de-sirous of initiating such a scheme. He added that in the meantime the Department of Agriculture was prepared to co-operate with any group of farmers in establishing accredited herds and areas, and that he was also considering the possibility of establishing two experimental areas where the full costs of eradication and the probable effect on the economic position of the industry might be studied.

“Considerable attention has been centred for some time on a suggestion that determined efforts should be made to eradicate bovine tuberculosis from the dairy herds in the Dominion, and many resolutions along these lines have been passed by farmers’ organisations,” said the Minister, who added that some clarification of the position appeared necessary.

THREE SCHEMES SUGGESTED. Three alternative schemes had been suggested:—(l) The complete coverage of tuberculin-testing of all dairy cattle in the Dominions; (2) tuberculintesting of all herds supplying milk for local consumption, and (3) a co-opera-tive accredited herd scheme. It was suggested that the first scheme could be completed within three years, and that afterwards a state of comparative freedom could be maintained by adequate veterinary service. The partial scheme covering cows used for liquid milk supply was thought in some circles to be sufficient to safeguard the local position, and also to form a basis for a gradual extension into all herds concerned in the export trade. “The co-operative accredited herd scheme would depend for its success on the voluntary efforts of dairy-farmers,” said the Minister. "This scheme has much to commend it, provided the same co-operative spirit is behind it as that obtaining in the eradication scheme in Denmark. The scheme could be put into operation in selected areas or districts by the voluntary efforts of a majority of dairy farmers in the area or district. After the majority had Carried out the testing on a voluntary basis, consideration could be given to bringing the minority in that area into the scheme by legislation, as is followed in Denmark.

“Any such areas or districts would become accredited areas in which all the dairy cattle would be free from the disease. Accredited areas could be gazetted and extended from time to lime, as obtains in the United States of America at the present time.

.EFFECT OF SCHEMES. “In reviewing the first two alternatives, the points io be considered are the burden of the cost on the Consolidated Fund, and the effect of consequent heavy replacement of cows on the total output of dairy produce in the Dominion in the case of scheme No. 1. To a much lesser extent, these two considerations will apply if schemes No. 2 oi’ No. 3 were to operate. A further point is the inequality of effect on individual farmers resulting from a wide variation in the possible incidence of reactors. “It is estimated that scheme No. 1 would cost in the vicinity of £2,300,000 in the first three years, and would entail thereafter an annual administrative expense of approximately £150,000. Scheme No. 2 would cost in the vicinity of £lOO.OOO for the first year, and £25,000 to £30,000 a year thereafter.

EFFECT ON PRODUCTION. “If scheme No. 1 were put into operation, the replacement of the reacting stock might well result in insufficient healthy animals being available to maintain the Dominion's herds at their present level other than through the retention of cows which otherwise would have been culled. The probable effect of this factor on total production cannot be estimated, and it migh l well result in considerable reduction for a few years. “Under schemes No. 2 and No. 3 there is not the same objection either, in regard to cost or their possible effect on the Dominion’s production. “It is estimated that the average incidence of tuberculosis in dairy covzs in the Dominion is in the vicinity of six to eight per cent,” continued the Minister. “It has been shown in certain instances, however, that the number of reactors may reach a considerably higher percentage in individual herds even as high as 50 to 60 per cen’ being recorded in certain cases. Many of the reactors in such herds would be animals affected with tuberculosis of a localised nature, and would not at the time of reaction constitute a danger tc human health by means of infection in the milk.

“It will be appreciated from this statement that certain individual farmers may have such a high incidence of the disease in their herds and be s affected that their livelihood would be materially interfered with for some years if scheme No. 1 were introduced. In such a case serious consideration would require to be given to the es tablishment of a pool fund, preferabl: on a co-operative basis, to which all producers would subscribe in order P smooth out the unequal effects on in dividual farmers. MOST SERIOUS ASPECT. “Perhaps the most serious aspect of the eradication of tuberculosis from dairy herds lies in the fact that the disease may be present in a variety of forms, varying from very mild . (i--which only a i'ew small spots of infection may be present) to very severe forms 'in which large areas of tissue ■are affected). In the mild cases the | general health of the animal may not ! be impaired, but in the severe forms 1 the animal's health is severely irnpair- | ed.

; “When the disease is present in the i milk secretion system grave danger to human health may result. Minor infection in muscular glands, however, does not present any serious danger to j human life. The intradermal test gives reactions in any stage, and reI suits in heavy eradication if all reactors are slaughtered.

“It will be appreciated that, once a policy is decided upon, the test used must be accepted as a final indicator to determine the retention or destruction of stock, and the Government hesitates to impose such a procedure on the industry until its full implications are known.

"In the meantime the Department of Agriculture is prepared to co-operate with any group of farmers for the purpose of establishing accredited herds and areas. I am also giving consideration to the possibility of establishing two experimental areas where the full cost of eradication and the probable effect on the economic position of the industry might be studied. This cannot be done during the current financial year. but. if practicable, such experimental areas will be set up in 1940.”

WAIRARAPA DISTRICT SUITABLE FOR EXPERIMENTAL AREA. BOROUGH INSPECTOR’S VIEW. “I consider the Wairarapa area would be an eminently suitable one for the establishment of an experimental area in accordance with the Minister’s suggestion,” said Mr T. A. Russell, Masterton Borough Sanitary Inspector. Mr Russel] said that for the past four years the borough had sponsored a testing scheme in relation to all dairy herds supplying milk for local con-. sumption and this, coupled with the | fact that a considerable amount of test-1 ing had been carried out in the Wairarapa district as a whole from Pongaroa to Featherston, should be a factor in determining the suitability of the Wairarapa as an area for experimental purposes.