722 Diseases of the Genital Organs 



damental atony was referable to the uterus. Prior to abor- 

 tion there was often a dirty sanious discharge from the 

 vulva for several days, and finally when the fetus was ex- 

 pelled it had undergone putrefaction and maceration. This 

 is highly characteristic of the metritis of pregnancy in ewes, 

 so far as- now known. McFadyean and Stockman in their 

 observations record that sanious vulvar discharge common- 

 ly occurs some days prior to the expulsion of the fetal cada- 

 ver, which, in their experience, was usually putrefying or 

 macerating. 



This is in marked contrast to the observations in cattle 

 abortion. Generally in cattle the expelled fetal cadaver is 

 fresh and shows merely traces of the beginning of decom- 

 position. In exceptional cases, as noted while considering 

 abortion in cattle, the embryo or fetus macerates or putre- 

 fies prior to expulsion, or it putrefies and is permanently 

 retained. The prevailing behavior of the uterus toward a 

 contained dead fetus is, therefore, essentially reversed in 

 the cow and the ewe. In the cow the endometritis at the 

 cervical end of the uterus has a marked tendency to cause 

 contraction of the walls of the comparatively sound ovarian 

 end of the uterus, through which the fetus, dead or alive, 

 is forced into the cervix, dilating the latter and causing in 

 turn expulsive contractions of the abdominal walls. But, 

 as pointed out, if the infection within the uterus spreads too 

 rapidly toward the ovarian end, or begins there and para- 

 lyzes the muscular walls, expulsion fails and retention with 

 putrefaction follows. Instead of such maceration being the 

 exception, it becomes the rule in ewes. This is probably 

 largely due to an earlier and more severe involvement of the 

 ovarian end of the ovine uterus. It may be due partly in 

 some cases to the existence of twin pregnancy. Twins rare- 

 ly perish simultaneously, and as a rule the first embryo to 

 perish is retained within the uterus until the second fetus 

 either perishes or reaches fetal maturity. Then the uterus 

 contracts and either twin abortion or birth and abortion 

 concurrently ensue. Thus, in twin abortion, the fetuses are 

 unlike in development and in post-mortem changes. One 



