SOME COMMUNICABLE DISEASES 357 



them for years (Fig. 89). To detect these carrier cases, as well 

 as others of more recent origin, recourse may be had to blood 

 tests. These tests show the presence or absence of antibodies 

 produced as a result of infection with the abortion germs, but 

 do not tell whether the germs are actually present. 



Treatment. — Immediately after an animal aborts the soiled 

 litter, fetus, and fetal membranes should be disposed of in a 

 sanitary manner. The stable floor is then to be disinfected with 

 a strong liquid disinfectant. If the afterbirth is retained, the 

 womb must be douched with blood-warm, 1 per cent, salt solu- 

 tion, otherwise pus is likely to accumulate and prevent concep- 

 tion. In other words, the cow will become a non-breeder or 

 is barren if not given proper care after aborting. At present 

 investigators are urging the use of a vaccine, composed of live 

 abortion bacilli, as a means of conferring immunity. This prod- 

 uct is injected subcutaneously in 30 c.c. doses at least two months 

 before the animal is bred. A bacterin containing millions of 

 killed abortion bacilli per cubic centimeter has been widely 

 used but the results obtained do not warrant recommending it. 



DOURINE 



Dourine is an infectious disease of the horse and ass trans- 

 mitted by copulation. It runs a course of from nine months 

 to two years and is fatal in about 70 per cent, of the cases. Until 

 1912 and 1913 no serious outbreak had occurred in the United 

 States since 1901. In June 1912, an outbreak of the disease 

 occurred in Montana. It proved to be so extensive that on Feb- 

 ruary 23, 1914, Congress granted $100,000, or as much thereof as 

 would be needed, to investigate, treat, and eradicate it. 



Cause. — It is caused by a protozoan parasite (Trypanosoma 

 equiperdum) which is found as an actively motile microorganism 

 in the blood. The period of communicability of this disease may 

 extend throughout the life of the infected animal. 



Symptoms. — There are many variations in the symptoms of 

 dourine, so it is impossible to describe a single case and at the 

 same time convey a good idea of the disease. Among the 

 usual symptoms in the stallion are an irritation and swelling 

 about the penis and soreness of the glands in the groin. Soon 

 vesicles appear and break, leaving irregular raw ulcers, which 



Digitized by Microsoft® 



