REPORT OF THE SECRETARY OF AGRICULTURE. 17 



31, 1918, amounted to only $32,000,000, as compared with $75,000,000 

 in 1914, a reduction of more than 50 per cent in less than five years. 

 Stated in another way, the death rate from hog cholera in the United 

 States was 144 per thousand in 1897, 118 in 1914, and only 42 in 1917, 

 the lowest in 35 years. 



The protective serum was used also at public stockyards dur- 

 ing the last year. Among the hogs received at market centers there 

 are many which are too light in weight for slaughtering and which 

 should be sent back to farms for further growth and fattening. For- 

 merly, because of the danger of spreading cholera, the Department 

 would not allow hogs to leave public stockyards except for immediate 

 slaughter. The result was that all light-weight hogs sent to the 

 markets were slaughtered. Some of these were young sows suitable 

 for breeding. Now the Bureau of Animal Industry treats these im- 

 mature pigs with serum and allows them to be shipped out as stockers 

 and feeders. During the past year more than 250,000 head were 

 handled in this way. Their average weight was approximately 100 

 pounds. It is probable that practically all of them were returned 

 to the markets later at an average weight of 250 to 275 pounds, mak- 

 ing an aggregate gain of about 40,000.000 pounds of pork. 



Tuberculosis. — Tuberculosis, the most widely distributed destruc- 

 tive disease that now menaces the live-stock industry, recently was 

 made a special object of attack. In cooperation with State authori- 

 ties and live-stock owners, a campaign was undertaken in 40 States 

 ^to eradicate tuberculosis from herds of pure-bred cattle, from swine, 

 and in selected areas. At present our efforts are concentrated on 

 the first project, since the pure-bred herds are the foundation of 

 our breeding stock. A plan adopted in December, 1917, by the 

 United States Live Stock Sanitary Association and representatives 

 of breeders' associations, and approved by the Department, was 

 put into operation with the assistance of a large number of herd 

 owners. Herds are tested with tuberculin, and any diseased ani- 

 mals are removed and the premises cleaned and disinfected. Sub- 

 sequent tests are made at proper intervals. By this means there 

 is being established an accredited list of pure-bred herds from which 

 breeding stock may be secured with reasonable assurance that it is 

 free from tuberculosis. The first list, consisting of more than 1,000 

 names of owners of herds of pure-bred cattle, representing tests made 



