gX8 Dourine. 



periods of improvement are observed in the course of the dis- 

 ease or complete recovery may take place. 



In rabbits a subcutaneous or intravenous injection results 

 sometimes in acute, septicemic, at other times in a chronic 

 affection. In the latter an inflammatory swelling of the genital 

 organs, falling of the hair, necrosis of the skin, crustaceous 

 eczema on the forehead, purulent conjunctivitis, or panoph- 

 thalmia is observed, while copulation of an affected with a 

 healthy animal produces in the latter a gangrenous inflamma- 

 tion of the genitals. Infected guinea pigs remain apparently 

 healthy in spite of the periodical appearance of the parasites 

 in their blood, and suddenly succumb months later. 



In dogs a warm and painful swelling appears at the point 

 of inoculation, also extensive edematous infiltration of the 

 abdomen, in the parts surrounding the genitals and in the 

 inguinal region; also acute balanitis; in bitches inflammation 

 of the vaginal mucous membrane with a profuse discharge 

 is observed. The back is sensitive, round flat swellings of the 

 size of the palm of the hand which again disappear within 

 2 to 3 days appear on the skin, in some cases an inflammation 

 of the joints, purulent conjunctivitis, and ulcerative keratitis 

 may be present. In the later stages rapid emaciation, in spite 

 of good appetite, stiffness of the hind parts, general hyperes- 

 thesia, and in the last stages complete inappetence without 

 fever, marked emaciation, as well as very laborious respiration 

 are noted. 



In dogs that are paired with affected animals an acute 

 inflammation of the external genital organs develops, in which 

 the discharge contains trypanosomes, and similar results are 

 obtained from an injection of blood containing trypanosomes 

 into the vagina of the bitch. 



In sheep plaques develop in different parts of the body, 

 which leave in their places large bare spots; besides this an 

 inflammation of the genitals develops while the general condi- 

 tion remains undisturbed for months. In cattle a positive result 

 of the infection can be only established by the demonstration 

 of trypanosomes in the blood. Fowl can be infected only ex- 

 ceptionally (positive results are reported by Yakimoff & Kohl). 



The natural infection is usually transmitted by coitus. 

 Dourine affects almost exclusively stallions and breeding mares, 

 and the disease has repeatedly been reproduced intentionally 

 by allowing affected mares to be covered by healthy stallions, 

 and healthy mares by affected stallions (Prince & Lafosse, 

 Trasbot, Azary, Marek). In studs it is, as a rule, mares covered 

 by certain affected stallions that become affected, and only much 

 later are other stallions infected as a result of an infection 

 through affected mares, and these may in their turn infect many 

 mares. 



During coitus the healthy genital organs are infected by 

 the secretion of the urethra or of the vaginal mucous mem- 



