CHAP. I. TUBERCULOSIS. ' 



muscles, &c. When the glands of the bowels are diseased, diarrhoea is 

 a prominent symptom. Tuberculosis of the udder presents itself as a 

 firm tumour-like area, generally in the upper part of the udder, which 

 has no tendency to suppurate (form matter), but steadily increases in 

 size until a large part of the udder becomes diseased and loses its power 

 of secreting milk. In the early stages the quantity of milk is actually 

 increased, but as the disease advances it becomes less and the quality 

 deteriorates, the milk of the affected quarter has, a thin bluish appear- 

 ance, and eventually quite alters in character, separating into a kind of 

 curds and whey. 



Tubercle bacilli are remarkably resistant to changes of temperature 

 and the action of disinfectants. Ingestion seems to be the most 

 common mode of infection, at any rate in the lower animals, and pro- 

 bably in man also. 



We cannot enter here into the question of the degree of certainty 

 attaching to the tuberculin test for the detection of the disease. 



In further reference to the transmissibility of bovine tuberculosis to 

 man, we take the following extracts from the Annual Report of the 

 Royal Veterinary College for 1907, written by Sir John M'Fadyean : 



" It will be remembered that in the course of an address delivered at 

 the Congress for the Study of Tuberculosis in London, in July, 1901, 

 Professor Koch renounced the opinion which he had formerly expressed 

 regarding the identity of human and bovine tuberculosis, and openly 

 declared that the question whether man could be infected from cattle 

 was unproved, but that if such transmission ever took place the occurrence 

 was so rare that it was not advisable to take any measures against it. 



" The controversy which was then started has been since maintained, 

 but fortunately it appears to be drawing to a close, at least with regard 

 to the main point of dispute. As a result of Koch's pronouncement a 

 Royal Commission was appointed in this country in the autumn of 1901 

 to investigate the relationship between human and animal tuberculosis, 

 and it has since been continuously engaged with this problem. Simul- 

 taneously experiments bearing on the same question have been carried 

 on in Germany, and during the course of the present year both the 

 English and the German Commissions have published exhaustive reports 

 giving the result of their researches to date. 



" The general plan of the experiments carried out in the two countries 

 was substantially the same, and, as might have been expected where 

 competent workers were engaged, the results are also in close agreement. 

 The English Royal Commission made a painstaking investigation of sixty 

 cases of tuberculosis occurring in human beings, and came to the con- 

 clusion that in fourteen of these the bacilli which caused the disease 

 had been derived from cattle. The German Commission similarly 

 investigated sixty-seven cases of the disease in man, and in eleven of 

 these they found bacilli which were identified by them as bovine bacilli. 

 In two of these eleven cases the patient had been infected both from a 

 human and a bovine source, but in the other nine the leeions contained 

 bovine bacilli only. 



