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the federal, state and county authorities have, between them, spent approxi- inately 150 million dollars on the eradication of tuberculosis.
(iii) The eradication of bovine tuberculosis in Canada.
a
16. There are four schemes under which attempts are being made to eradicate bovine tuberculosis in Canada. The first in point of time, but perhaps the least successful, provided for the free testing of cattle with tuberculosis in herds supplying milk for consumption within any municipality which enforced certain regulations regarding milk within its area, and applied for assistance in the control of bovine tuberculosis and for the compensation of owners of tuberculous cows slaughtered as a result of the test. The regulations of the municipality were bound to require, in addition to a minimum hygienic standard for dairies supplying milk within its the boundaries, that no dairy should sell unpasteurised milk within municipality after two years had elapsed from the date of the first test with tuberculin of the cattle belonging to the dairy in question, unless veterinary inspector certified that such cattle were free from tuberculosis. Cattle in dairies the milk from which was sold to dairy companies equipped with adequate pasteurising plants who pasteurised the milk in question, were Cattle in other dairies were tested not necessarily tested with tuberculin, with tuberculin and examined clinically by a veterinary inspector of the
to Cows discovered dominion government.
open be suffering from
Cows reacting to tuberculosis were required to be slaughtered forthwith. the test, but not suffering from open tuberculosis, might either be slaughtered or retained in the herd. If the latter alternative was chosen, milk from that dairy was required to be pasteurised. Compensation was paid for cows slaughtered, up to one-half of their appraised value in the case of cows with open tuberculosis, and up to two-thirds of their appraised value in the case of other reacting cows. Cows bought by owners of herds which were under control were required to pass the tuberculin test before being placed with healthy cows.
17. This plan was brought into operation in 1916, and by 1924 thirty municipalities were receiving assistance under it. By that time, however, it was clear that satisfactory results could not be expected from it, and no further municipalities have been admitted under it. The reasons for the comparative failure of this scheme were the reinfection of tested herds by contact with untested herds selling pasteurised milk, and the reinfection of It was herds by cattle bought from outside sources to replenish wastage. also suspected that reacting cattle were being deliberately sent into herds under control with a view to securing compensation.
18. The second scheme to be adopted as part of the campaign against bovine tuberculosis was the accredited herd plan. This scheme is only open to owners of herds in which not less than five animals are pure-bred and not more than two-thirds of the total cross-bred. Herds under this scheme are tested by the veterinary inspectors of the federal Department of Agriculture. Accredited herds are those in which no reactors are found at two successive annual tests or three successive semi-annual tests. Every herd owner entering the scheme undertakes, in consideration of the assistance given him in the testing of his herd, to observe various hygienic precautions against the spread of tuberculosis, to introduce no animal into his herd except under conditions which secure that it shall be free from tuberculosis and to remove all reacting animals from his herd for immediate slaughter. Compensation is paid for animals slaughtered up to two-thirds of their appraised value, subject to a maximum compensation which has been varied from time to time. The United States and the Dominion of Canada have each agreed to accept a certificate of accreditation issued by the other as though it were issued by itself. The number of accredited herds has increased rapidly in recent years, and in 1932 there were 5,533.
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19. Herds which are excluded from the accredited herd plan may become supervised herds. This plan is not the subject of any official regulations, but is based upon an agreement with the Department of Agriculture signed by the owner of the herd in question. Under this agreement, in consideration for his herd being tested with tuberculin by the department, the herd owner undertakes to carry out the instructions of the department's veterinary officer, to slaughter all reacting cattle and to take necessary precautions against the reintroduction of tuberculosis into his herd either by the purchase of new stock or in other ways. No compensation is paid for cattle slaughtered. Under this plan 4,855 herds had been tested by 1932, at which time 1,842 herds were awaiting test. As the restricted area plan, to which we next refer, extends, supervised herds are comprehended in the larger scheme and are no longer dealt with as individual herds.
20. The restricted area plan was brought into operation by an order in council dated the 4th May, 1927. It provides that, on the application of a provincial government, and with the consent of two-thirds of the cattle owners in the proposed area, the Dominion government may declare an area a restricted area. Under the restrictions which are thereupon imposed on the movements of cattle into such an area, cattle which are neither drawn from accredited herds, nor pass a tuberculin test, are prohibited from entering the area except for immediate slaughter. Cattle within the area are tested with tuberculin as soon as possible after the area is proclaimed, and thereafter as often as is required by the veterinary director-general. Reactors to the test are slaughtered without delay, and compensation is paid to their owners up to two-thirds of their value, subject to a maximum compensation. Under this plan 1,627,473 cattle had been tested by the
year 1932, and 1,242,379 animals were being supervised under it.
In many restricted areas the incidence of tuberculosis had been reduced to very small proportions. In the province of Prince Edward Island, for example, the whole of which constitutes a single restricted area, the incidence of tuberculosis was in 1929 no more than 0-15 per cent.
21. The extent of the effort which is being made in Canada to control bovine tuberculosis may be judged from the fact that in the year ended the 31st March, 1932, nearly one million tests were carried out on Over 800,000 animals. Among these, nearly 20,000 reactors were discovered and slaughtered, and compensation amounting to 665,000 dollars was paid for them out of public funds. As in the United States, a very hopeful view is taken by those in charge of these operations of the prospect of reducing tuberculosis to manageable proportions.
22. In addition to the efforts which it is making to eradicate bovine tuberculosis, the Dominion government has instituted a plan under which it is hoped eventually to reduce the incidence of contagious abortion. This plan resembles the supervised herd plan in that it is based on an agreement between the herd owner and the Department of Agriculture, under which, in return for assistance in making blood tests of his cattle, the owner under- takes to carry out the instructions of the department's veterinary officer. The methods of eradication employed, however, are different. The method of the isolation of the reacting section of the herd and its gradual elimination as uninfected young stock are reared is contemplated as an alternative to the method of immediate slaughter in the eradication of this disease. The sale of reacting animals is also permitted, but only into herds already infected with the disease, and on disclosure of the fact that the animal has reacted, to the intending purchaser. At the end of the year 1931-32 only 81 herds were under supervision, of which 70 had already been tested and 11 were awaiting test.
(iv) The control of the milk supply and of cattle diseases in Denmark. 23. The milk supply of Copenhagen is drawn from farms which are subject to a monthly veterinary inspection. This inspection refers not only to the health of the cows, but also to the cleanliness of the cows and of the
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