144 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



Approximately 80 veterinarians were maintained in the field for 

 the entire year. In localities where the services of veterinary prac- 

 titioners were not available bureau inspectors continued to apply 

 the preventive serum treatment in infected herds and to immunize 

 exposed animals. Where veterinary practitioners were available, 

 bureau activities consisted in the investigation of reported outbreaks, 

 diagnosing swine diseases, assisting the local veterinarians in diag- 

 nosmg and in treating herds in cases of cholera, and advising farmers 

 as to cleaning and disinfecting premises and the proper care of swine 

 herds. 



Jn the course of their activities bureau veterinarians attended 1,074 

 meetings at which 67,408 persons were present, and 4,343 demonstra- 

 tions in the use of the serum treatment were given before a total of 

 26,428 farmers and others. At these demonstrations 88,846 hogs were 

 treated. Investigations were made on 47,137 premises, 5,390 autopsies 

 were held, and cholera was diagnosed in 4,079 cases. A total of 1,401 

 infected premises were quarantined or carded, 439 places were 

 cleaned and disinfected, 171,325 persons interested in hog production 

 and the control of hog cholera were interviewed, and 36,787 hogs 

 were treated in connection with the efforts to assist practicing veteri- 

 narians and improve their technic. 



The year brought about a marked change in the attitude of veteri- 

 narians and others regarding the diagnosis of swine ailments allied 

 with hog cholera. Farmers and practitioners .alike have realized 

 that hog cholera is still the predominant disease affecting swine herds 

 and that the serum treatment is the most reliable agent for protection 

 against losses. There are still many veterinary practitioners, how- 

 ever, who need to exercise more care in the handling of serum and 

 virus, in their technic of administration, in the use of the ther- 

 mometer, and in learning the history of cases. 



The fine spirit of cooperation shown by the extension divisions of 

 State agricultural colleges is gratifying. Through the vigilance and 

 cooperation of county agents many outbreaks of hog cholera were 

 reported to bureau and State veterinarians, thus makiitg it possible 

 for them to give assistance to swine owners early in the development 

 of the disease and before serious losses had occurred. 



PATHOLOGICAL DIVISION. 



The Pathological Division under the direction of Dr. John S. 

 Buckley, chief, has continued the scientific investigation and diag- 

 nosis of animal diseases, the testing of biological products manu- 

 factured and marketed under Federal control, and the study of plants 

 poisonous to livestock. 



RESEARCH ON DISEASE PROBLEMS. 



BOVINE INFECTIOUS ABORTION. 



• Endeavors have been continued to acquire further information 

 relative to the value of biological preparations for controlling abor- 

 tion losses. Studies in infected herds have indicated that living- 

 abortion organism vaccine may be employed advantageously in con- 

 junction with sanitary measures. The degree of immunity conferred 



