686 PROCEEDINGS OF SECTION I. 



This percentage of 8-8 compares favorably with the figures given 

 by Legge and Session for various Continental towns, thus : — 



Leipzig, 1897, number of cattle slaughtered 27,191 



Percentage tubercular 36'4 



Carlsruhe, 1895, number of cattle slaughtered 9,496 



Percentage tubercular 10-4 



Stettin, 1895, number of cattle slaughtered 8,818 



Percentage tubercular 22-7 



Amongst sheep tubercular lesions of the liver have been twice met 

 with. 



I will not discuss in this paper the possibility of danger to human 

 beings from the products of tubercular cattle. These dangers may 

 be divided into two groups, according to the nature of the foodstuffs, 

 viz. : — (1) The meat of tubercular animals, and (2) the milk of such. 

 The latter is outside the province of this article. Authorities differ 

 upon the first group, though the majority consider there is a decided 

 danger in eating partially cooked meat containing " bovine tubercle 

 bacilli," and all agree as to the advisability of removing all the diseased 

 parts. 



But what I particularly desire to ascertain and to ask a remedy 

 for is the means of preventing the spread of the disease. Year by 

 year hundreds of cattle over vast areas are affected ; they spread the 

 disease further and further afield, and the monetary loss to cattle- 

 owners, not to speak of the danger to human beings, must be great 

 and ever-increasing. Can nothing be done to check this scourge ? 

 Can no means be taken to prevent its extension ? The first question 

 to be decided is what is the means of spread (a) in cattle, {b) in pigs. 

 This having been decided, we then come to the second question : What 

 means can be recommended to limit its extent ? 



Indications of the Means of Spread in Cattle. 



On consulting the tabulated results it will be seen that in 76-4 per 

 cent, of the cases the lungs were affected, in 34 per cent, these alone. 



The retropharyngeal glands were tubercular in 55-5 per cent., 

 and these alone in 33-3 per cent. In only four instances (-83 per cent.) 

 were the lesions generalised. In 13 cases the glands draining the 

 scrotal pouch were affected, evidently indicating an infection of the 

 wound of castration. Cases not included in the above groups in which 

 other organs were diseased form a small minority of 30 (-83 percent.), 

 all connected with the alimentary canal. 



The small percentage of these in which the parts connected with 

 the alimentary canal were affected alone negatives, I think, the likeli- 

 hood of food infection. This is supported by the fact that cattle rarely 

 browse over the same tract as one of their fellows, and this would lessen 

 the risk of such infection by contaminated pastures. 



We see, instead, that the chief burden falls on the lungs and glands 

 in the throat, and next to them are the retropharyngeal glands. This 

 suggests at once inhalation of the tubercle bacilli, which would draw 

 them either directly into the lungs or else would allow of their arrest 



