GRANULAR VENEREAL DISEASE AND ABORTION IN CATTLE. 47 



Case 19. — Aged. Length of fetus, 9 inches. Uterine seal destroyed and cervical 

 canal dilated. 



Exterior of uterus pale yellow, the walls three-eighths of an inch thick, edematous, 

 from which the chorion was completely detached, macerated, and very fragile. 

 Faintly sweetish odor. Utero-chorionic space filled with a thin liquid in which 

 floated dirty-gray flocculent masses and some viscid mucus. 



The fetal membranes were edematous and brownish-green. 



Cotyledons 1 to 2 inches, scarlet, necrotic, and readily detachable from their stalks. 



Case 20. — Aged. Length of fetus, 11 inches. Uterine seal intact. 



Radiating from the internal os for 12 inches in the utero-chorionic cavity is a dirty 

 yellowish-gray sticky exudate. Uterine mucosa injected, submucous petechiee. 

 The uterine walls at the apex of the gravid horn are one-half inch thick and very 

 edematous. 



Case 21. — Aged. Fetus 38 inches long. Uterine seal unbroken. 



Exudate commences about 6 inches from the os uteri internum and extends to 

 within 12 inches of apex of cornua, completely encircling it. The internal os is 

 surrounded by thickly diffuse placentae showing abundant inter-placental hemor- 

 rhages. Apparently the diffuse placenta and close apposition of uterus and chorion 

 explain the absence of the exudate at this point. 



The exudate is chestnut-colored, very tough, and sticky. It is collected most 

 prominently about the cotyledonal stalks, in masses often one-half inch wide by 

 one thirty-second to one-sixteenth inch thick. Portions of exudate lie free in cavity. 



Case 22. — Aged. Fetus 36 inches long. Uterine seal intact. 



Radiating from the internal os for a distance of 8 to 10 inches is a small amount 

 of very sticky, tough, chocolate-colored exudate. Lesser quantities are observed 

 near the apex of the gravid cornu. 



The findings of Bang, McFadyean, and Stockman, along with those 

 recorded above, seem to justify the conclusion that the abortion 

 exudate is an essential and universal phenomenon in contagious 

 abortion. It does not show that the presence of the abortion exudate 

 in any stated amount must be followed by abortion, but rather that 

 its presence imperils the life of the fetus. 



AVENUE OF INFECTION. 



The two natural avenues of infection suggested for cattle abortion 

 are the genital tube and the alimentary canal. McFadyean and 

 Stockman, and to a lesser degree Bang, consider the alimentary 

 tract the chief avenue of infection and submit experimental evidence 

 in which animals so exposed have aborted, or, having been killed 

 while yet pregnant, have revealed the exudate, and bacilli in the 

 utero-chorionic cavity. They have not shown conclusively that other 

 means of infection were eliminated. Ordinarily the experimenter 

 could not know that the Bacillus abortus was not already in the 

 utero-chorionic cavity or could not invade it through other avenues. 



The infection by ingestion, as well as the experimental methods of 

 intravenous and hypodermic inoculations, assume that the infection 

 enters the blood and finally reaches the utero-chorionic space. But 

 the supposed pathway by which the infection thus gains the utero- 

 chorionic cavity is not stated. Presumably under this hypothesis 



