EXPERIMENT STATION REPORTS. 251 



diagnosis of blood samples for bovine infections abortion, bacteriological 

 examination of tissues, spntnm for tubercle bacilli, swabs from nasal 

 and throat passages, and the preparation of autogenous vaccines have 

 occupied my attention. 



Three tri^js have been made during the year which will be discussed in 

 this report. 



In resuming the investigations in bovine infectious abortion, it has 

 been m}' plan to continue four of the problems which were begun in 

 191G, to continue studies on two problems on which Dr. Stafseth has al- 

 ready-reported and to work out problems which suggest themselves from 

 time to time. The four problems begun in 191 G are: 



1. The immunization of cows and heifers against infectious abortion 

 namg Bad . adortns (Bang). 



2. The routes through which Bact. ahortiis gain entrance to the body. 



3. The bactericidal effect of different chemical specifics when used 

 in vivo against Bact. ahortus. 



4. A study of different strains of Bact. ahot^ttis. 



The problems of Dr. Stafseth's on which studies were continued are : 



1. Tlie specificity of the intradermal test and its value in differen- 

 tiating between infection and immunity. 



2. The isolation and cultivation of Bact. ahortus. 



A technical bulletin which details the data and results of the im 

 munization problem is now in the process of preparation. 



During the 3'ear, there were received 194 blood samples (exclusive of 

 the experimental samples) for the ai)plication of the agglutination and 

 complement fixation test for infectious abortion of which 64 or 32 per- 

 cent gave positive reactions to one or both tests. 



Four samples of sputum from humans and five specimens of tissue 

 from chickens were examined for the presence of tubercle bacilli of 

 which one of the former and two of the latter were positive. 



There were received a total of twenty different specimens for bacteri- 

 ological examination. 



A trip was made to a farm near Aloha, Michigan, February 3, 1920, 

 for the purpose of ascertaining the cause of an epizootic of abortion and 

 wasting disease in a flock of goats. The findings were reported in the 

 April number of the M. A. C. Quarterly. A summary of the findings is 

 as follows : 



The flock of Angora goats (109 in numl)er) was shipped from the 

 southwest part of the United States to northern Michigan in November, 

 1919, arriving in a partly starved condition. About two weeks after 

 their arrival they began losing their young prematurely at the rate of 

 one to four a day. The symptoms of the wasting disease were a great 

 loss of flesli, general weakness, diarrhea, moving about slowly, drooping 

 of the ears, watery appearance of tlie eyes, no resistance when liandled, 

 appetite nninipaired, occasional bleating and cougliing, body tempera- 

 ture elevated and pallor of the visible mucous membranes. Tlie course 

 of the disease usually ran from tw<j to eight weeks. No affected animals 

 recovered. 



A small micrococcus was isolated from the heart blood, liver and 

 spleen of affected animals and from the stomach of an aborted fetus. 



The organism proved to be Micrococcus caprinus. This disease (known 



