GRANULAR VENEREAL DISEASE AND ABORTION IN CATTLE. 41 



The definite clinical diagnosis of impending abortion is essen- 

 tially impossible until the condition has so far advanced that the 

 preliminary acts of abortion, as dilation of the cervical canal, pro- 

 trusion of fetal membranes, etc., have become established. The deter- 

 mination of the fact that abortion has occurred must be based upon 

 the recognition of the expelled fetus or afterbirth as belonging to 

 the animal, or, if it is known that she has been pregnant, it must be 

 established by rectal or other examination that pregnancy has 

 terminated. 



The differential diagnosis between accidental and contagious 

 abortion is largely impracticable in the living animal. It has been 

 proposed to differentiate them in a variety of ways; for example, to 

 separate the two classes of abortion by recognizing the presence of 

 the Bacillus abortus in the placenta or uterine exudate of the one 

 group while it is absent in the other. While some have laid claim to 

 the possession of such skill, the accuracy of the conclusion that 

 merely negative findings indicate the absence of contagious abortion 

 does not seem wholly warranted. 



McFadyean and Stockman, Sven Wall, Holth, and others claim 

 much for the diagnosis of the disease by means of the complement- 

 fixation and agglutination tests. Thus far, however, it has only 

 been shown according to data submitted that certain animals which 

 had recently aborted reacted. They have not shown that all reacting 

 animals are bearers of the infection of abortion, nor that all bearers 

 of the infection react. The character of the conclusion from the 

 data assembled is well expressed by Wall: "A reaction indicates 

 that the animal is or has been infected with contagious abortion." 

 Animals which had aborted quite commonly reacted more than two 

 years after abortion. Apparently an impending abortion may not 

 ordinarily be foretold by these tests. 



The post-mortem diagnosis of contagious abortion appears to be 

 more certain and the phenomena fairly well established, especially 

 in relation to the presence of the abortion exudate. This exudate, 

 in the present state of our knowledge, is characteristic and con- 

 clusive. However, post-mortem examinations upon cows which 

 have recently aborted have been all too few in number, but the 

 phenomena presented are very uniform. We have had opportunity 

 of making post-mortem examinations upon seven recently aborted 

 cows and heifers, with the following results, which were in each case 

 essentially identical : 



Case 1. — A 2-year-old Hereford heifer shipped from Garden City, Kans., on May 17 

 to Kansas City and unloaded the following morning. It was found that during the 

 night of May 19 she gave birth to a small, weak, live calf, at apparently about the 

 seventh month. She was slaughtered about 11 a. m. The heifer was in good general 

 condition and apparently healthy. 



