Tuberculosis. 125 



calves from diseased mothers. With valuable breeding 

 stock, the loss caused by immediate slaughter would be 

 too great. The herd may be separated into the affected 

 or reacting, and the healthy. The two herds should be 

 kept in separate barns and pastures; the calves of the 

 diseased animals should be removed at birth and fed on 

 the milk of healthy animals or on the milk of the dis- 

 eased animals which has been heated to at least 160 F. 

 so as to destroy any tubercle organisms it may contain. 

 It has been shown many times in Denmark and in this 

 country that by this method a diseased herd can be put 

 on a healthy basis within a few years and at very slight 

 expense. Any farmer who wishes to employ this system 

 should apply to the state authorities connected with the 

 control of contagious diseases of animals for more de- 

 tailed advice. There is no successful practical means 

 at present of protecting cattle against tuberculosis by 

 vaccination. Certain methods have been widely adver- 

 tised as efficient, but are not a practical success. 



Tuberculosis of swine. Hogs acquire the disease 

 very easily by the ingestion of contaminated food, such 

 as skim milk, butter-milk, slime from cream separators, 

 or from cattle in feed lots. The parts of the body most 

 often affected are the glands of the head, neck, and in- 

 testines. The liver may show large rounded nodules, 

 yellowish-white in color, or minute nodules in great 

 numbers. The spleen often shows large nodules and the 

 lungs many small ones. 



Since the larger number of hogs are sent to market be- 

 fore they are a year old, the disease does not usually 

 make such headway as to cause any visible symptoms. 

 The tuberculin test has been used in the case of hogs, 

 but it is much more difficult to apply than with cattle. 



