THIRTEENTH ANNUAL YEAR BOOK— PART XI 565 



TUBERCULOSIS. 



The subject of tuberculosis as it affects the cattle and swine 

 industry of the state is an all important question and whilst no 

 attempt has been made at an organized campaign against tuber- 

 culosis, yet this department has tested a great many cattle and 

 we are pleased to say that the percentage of tuberculosis found 

 in bovine herds at present is no higher than a decade ago, in some 

 instances a marked improvement has been made. The repeated 

 testing of the state herds together with the remodeling of the 

 barns at the state institutions and the judicious use of disin- 

 fectants at various periods has not only reduced the percentage 

 of tuberculosis to the merest minimum in some herds but has 

 fully demonstrated in others that herds quite seriously affected 

 with tuberculosis may be cleaned and kept clean as regards 

 this disease. 



Apart from the testing of state herds it has been the policy of 

 this department, upon receiving notice from an inspector in 

 charge at any abattoir where Iowa hogs and cattle have been 

 slaughtered, to go to the premises from whence the cattle or 

 hogs were shipped to investigate the conditions there. When we 

 find infection in a bovine herd we have invariably applied the 

 tuberculin test. In this way we are trying to trace the disease 

 to its source. 



Tuberculosis whilst not apparently on the increase in the bovine 

 herds steems to be increasing rapidly in swine. The following let- 

 ter from Dr. A. D. Melvin, Chief of the Bureau of Animal In- 

 dustry, Washington, D. C, gives the government figures con- 

 cerning the number of hogs found tubercular on slaughter at 

 the abattoirs within the state: 



Washington, D. C, Nov. 27, 1912. 

 Dr. J. I. Gibson, State Veterinary Surgeon, 

 Des Moines, Iowa. 

 Sir— Replying to your letter of the 11th inst, our reports show that 

 out of 2,555,576 hogs inspected at 12 stations in Iowa during the fiscal 

 year 1912 the number of cases of tuberculosis found was 167,677. Some 

 of these hogs no doubt came from adjacent states, but I believe that 

 most of them were purchased in Iowa. Undoubtedly most of these cases 

 were developed in the hogs through infected cattle by feeding infected 

 dairy products, following infected cattle in feed lots, and feeding dead 

 and infected cattle to hogs. Very respectfully, 



(Signed) A. D. MELVIN, 



Chief of Bureau. 



