Infections of the Gravid Utei us 



795 



and cause it to move. So far as I have been able to observe, 

 the chorion illustrated in Fig. 230 is representative of 

 prompt abortion. Delayed abortion may cause such disin- 

 tegration of the chorion as to destroy the plain record here 

 shown of the progress of infection. 



Abortion in mares is accordingly, so far as now known, 

 always a result of cervical endometritis, combined with a 

 mortal disease of the embryo or fetus. The invasion of the 

 fetus is identical with the invasion of the fetus in the cow. 



Fig. 230— Fetal Placenta of Abortion. 



/, Parturient rent in chorion ; z , necrotic area opposite the OS uteri inter- 

 num ; J, inflamed area radiating from cervix toward ovarian end of 

 uterus ; 4, gravid horn ; 5, nou-gravid horn. 



The infection grows through the chorion at the necrotic cer- 

 vical area, through the continuous inflamed area (Fig. 230, 

 3) , or through the inflamed tip of the chorion located in the 

 non-gravid horn. When the allantoic fluid has been reached, 

 the invasion may continue through the urachus, but usually 

 penetrates the amnion and, suspended in the amniotic fluid, 

 is swallowed by the fetus. Then sepsis or dysentery may 

 follow, with fetal death. Fetal death may also follow ex- 

 tensive placentitis owing to asphyxia or to placental sepsis. 

 The endometritis at the cervical end of the uterus awakens 



