General Infections of the Genitalia of Sheep and Goats 723 



twin is smaller than the other. It had perished at an early 

 date and had undergone partial maceration or desiccation. 

 Such is the rule in twin abortion in the cow and almost with- 

 out exception in twin abortion in the mare. The same con- 

 dition is observed in twin abortion in woman. In swine 

 (presumably also in carnivora) embryos often perish but, 

 so long as other healthy embryos exist, the expulsion of the 

 cadavers is inhibited until all have perished or time for 

 parturition has been reached. In other instances fetal re- 

 tention with maceration is apparently referable to an in- 

 tense sclerotic or adhesive cervicitis which prevents cervical 

 dilation and thus incarcerates the fetal cadaver. In some 

 years this becomes somewhat common in certain flocks, and 

 ewe after ewe succumbs. In these instances there are ex- 

 pulsive contractions of the abdominal walls without concur- 

 rent contractions of the uterine walls of such power as to 

 dilate the cervical canal. The abdominal straining forces 

 the gravid uterus into the pelvis, pushing the cervix in front 

 of it through the vulva to the exterior — prolapse of the 

 cervix. 



The studies of Carpenter and myself in the outbreak 

 mentioned failed to establish clearly the etiology. Carpen- 

 ter recognized a spirillum in the uteri of three out of eight 

 slaughtered ewes. Two of the ewes carrying spirilla had 

 aborted, and one had given birth to a viable lamb. In only 

 one uterus was the spirillum recognized unassociated with 

 other bacteria (pure culture). Bacteria were recovered 

 from the uterus or placentae of each of the eight ewes ex- 

 amined. The list included, in addition to the spirillum, 

 colon-aerogenes, streptococci, staphylococci, and short oval 

 rods in pairs. 



Experimentally we failed to establish any important facts. 

 We purchased two pregnant ewes which were wild and 

 placed them in my experiment stable, where they were very 

 timid and uneasy. As is usual, the seller reported that he 

 had observed no abortions or disease of lambs in his flock. 

 Each ewe received in her jugular 10 cc. of composite stom- 

 ach fluids from three fetuses, the fluid from each source con- 



