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notified to the local authorities, and by them slaughtered, subject to the payment of compensation. In recent years, the number of animals slaughtered under this order are between 15,000 and 19,000, and the compensation paid has amounted to between £60,000 and £70,000 a year, exclusive of the cost of administration (paragraphs 102-113).
(17) Under the epizootic abortion order of 1922, certain specified precautions must be taken against bringing cows which have aborted into contact with other cattle. This order is generally considered ineffective (paragraphs 114, 115).
(18) The principal effect of the acts and orders affecting the production and sale of milk is to require that the milk of a cow recognised to be diseased should not be sold, to give power to local authorities to appoint veterinary inspectors, who must examine herds in certain circumstances, and to define special grades under which milk may be sold (paragraphs 116, 117).
(19) In Scotland, all dairy herds must undergo a clinical examina- tion at least once every year, and in many parts herds are inspected three or even four times a year. In England and Wales the position is less satisfactory. Though in some counties routine clinical inspec- tion is undertaken, this is not compulsory, and experience shows that the execution of the minimum requirements of the order does not reduce the degree to which milk is infected with tuberculosis (para- graphs 118, 119).
(20) There are four kinds of milk officially recognised under the milk (special designations) orders, namely:-
(a) certified milk, or milk from herds free from tuberculosis, which
is bottled on the farm;
(b) grade A tuberculin-tested milk;
(c) grade A milk;
(d) pasteurised milk (paragraph 120).
(21) Less than 1 per cent. of dairy cows are in herds officially recognised as being free from tuberculosis. The sale of designated milk as such is far below the supply and shows no sign of expansion (paragraph 121).
(22) The measures discussed have not appreciably reduced the incidence of tuberculosis among dairy cattle. Infected cows are removed too late to prevent the infection of other cattle or appreciably to improve the purity of the milk supply. At the price at which it is placed on sale, there has been little demand for graded milk from tuberculin-tested herds (paragraphs 122–124).
Possible lines of administrative development.
(23) The three principal proposals promising an improvement of the milk supply are:-
(i) an extension of routine veterinary inspection;
(ii) an active policy for the eradication of bovine tuberculosis;
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(iii) the grant to large urban authorities of the right to require pasteurisation of milk other than that produced from herds free from tuberculosis (paragraph 126).
The further development of the veterinary inspection of dairy cattle.
(24) Though clinical inspection reduces the amount of tuberculous milk passing into consumption, it can never render the milk supply safe as-
(i) some cows showing no clinical symptoms yield tuberculous
milk;
(ii) cows reach the stage of giving tuberculous milk between the
visits of the inspector;
(iii) milk is often contaminated with tubercle bacilli present in
infected dung or dust.
Experience shows that clinical inspection cannot be relied on to reduce Infection to really small proportions, though it has not yet been sufficiently developed to show how effective it might be in this direction (paragraphs 127-132).
(25) A reduction in the infection of milk with bovine tuberculosis is not accompanied by a proportionate reduction in the infection in man, and the results of clinical inspection may prove disappointing from this point of view. Routine clinical inspection will not greatly reduce the incidence of bovine tuberculosis by removing infected cows from herds, but it will improve the day-to-day management of herds, awaken farmers to the necessity of eradication and benefit country as well as town populations (paragraphs 133-136).
Methods of eradication.
(26) The total eradication of bovine tuberculosis from all herds is the only complete solution of the problem of tuberculous milk. Self- supporting herds may be cleared by the Isolation or elimination of infected cattle; but most herds are not self-supporting, and some special provision must be adopted for them. The specialisation of herds for breeding and milk production respectively is economically advantageous and firmly established and cannot be reduced. campaign based from the beginning on progressive formation of clean areas would require compulsion at the outset and would greatly inter- fere with the free flow of cattle on which our whole cattle industry is based, and cannot now be undertaken (paragraphs 137-142).
A
(27) It is therefore essential to prevent the infection in transit of tuberculosis-free cattle. The practical difficulties involved will be considerable, but not insuperable (paragraph 143).
(28) Farmers may reduce tuberculosis in their herds by the slaughter, the segregation, or the sale of reacting animals.
Any
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