BUEEAU OF AXI]\IAL, INDUSTRY. 239 



fanners do not take prompt action in calling for assistance when 

 trouble appears in their swine herds. Too often there is a long 

 delay from the time the hogs sicken until trained assistance is 

 sought, and in many cases wdien cholera is present the disease has 

 advanc.d to such a stage when the inspector reaches the outbreak 

 that many hogs are dead or b 'yond receiving b 'nefit from the serum 

 treatment. 



The year had the usual quota of misguided information, incorrect 

 diagnoses, and improper methods of handling outbreaks of cholera. 

 " Breaks," or the recurrence of hog cholera in herds supposed to 

 have been immunized against the disease, continued to give some 

 trouble. "VVTiile special attention was given to these breaks, in many 

 cases no positive causes could be determined as being wholly respon- 

 sible for the return of susceptibility in the herds. In other cases 

 bureau inspectors were able to trace the unfavorable results to non- 

 virulent or attenuated virus, underdose of either serum or virus, and 

 improper care of the animals following inoculation. 



In the course of the year bureau veterinarians held or attended 

 1,418 meetings, at which there was an attendance of 84,896 persons, 

 and 4,855 demonstrations in the use of serum and virus were given, 

 in which 108,472 hogs were treated before 21,547 persons interested 

 in the control of hog cholera. Investigations were made on 51,306 

 premises, 5,182 autopsies were held and cholera was diagnosed in 

 4,081 cases, and 1,632 farms were quarantined. Interviews to the 

 number of 183,545 were had with farmers, swine growers, veterina- 

 rians, merchants, bankers, and others interested in the control of hog- 

 cholera losses ; practicing veterinarians were assisted in treating 892 

 herds containing 34,820 hogs. There were reported during the year 

 from all sources 7,074 outbreaks of hog cholera. 



PATHOLOGICAL DIVISION. 



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

 Buckley, chief, has continued the investigation of animal diseases 

 and factors connected with the control of disease. 



A great many specimens have been examined throughout the year 

 for the purpose of diagnosis, and while in a measure they have ham- 

 pered research studies, they have also furnished clues that have ad- 

 vanced our knowledge of special diseases. 



RESEARCH ON. DISEASE PROBLEMS. 



BOVINE INFECTIOUS ABORTION. 



In studying the value of biological products in combating infec- 

 tious abortion of cattle, a practice has commonly been made of esti- 

 mating their action by considering the calving or abortion records of 

 treated subjects. During the last year the problem was attacked in 

 a somewhat different manner. An experiment was undertaken with 

 the object of ascertaining whether, by repeated injections of abortion 

 bacterin (suspensions of killed abortion bacteria), the multiplication 

 of abortion microorganisms in the udders of affected animals could 

 be overcome. • 



Seven cows which eliminated BacteHum abortus in their milk 

 were given 6 subcutaneous injections of abortion bacterin at weekly 

 intervals, while 8 cows which also eliminated the organism were 



