1084 Veterinary Obstetrics 



kept in stables with diseased cows, if the heifers are not 

 groomed. 



The relation of the disease to abortion in this herd was appar- 

 ently very important. In Herd i abortion was persistent but 

 scattering. While no large number of abortions occurred in any 

 month or year during the existence of the herd, the total for the 

 three years was of distinct economic importance. 



In Herd 2, abortion was far more frequent and serious. It 

 might be said that abortion was comparatively as much more 

 frequent in this herd than in the first one, as the vulvar lesions 

 were more abundant and intense. That is, the number of the 

 abortions in the two herds was approximately parallel to the 

 respective intensity of the lesions in the two herds. 



In this herd, 156 cows were bred to calve during 1908, and 

 kept on the farm until the result was known. Of these, 42, or 

 27%, aborted; and 14, or 9 %, were slaughtered because of sterility. 

 Four cows or heifers, which had been bred and conceived, were 

 sent to the butcher as sterile, after having aborted. Exact sta- 

 tistics for prior years are not available, but abortion and sterility 

 have been causing serious losses for a number of years. The 

 ravages of abortion reached the climax in 1908. As accurately 

 as statistics can be readily compiled, the losses in the herd, be- 

 tween January 1901 and May 1905, averaged 0.5 abortions per 

 month; between May 1905 and March 1907, 0.86 abortions 

 per month ; and during 1908, 3.5 per month. 



Most of the animals aborting in 1908, and indeed throughout 

 the history of the herd, have been young cows and heifers. 

 Very largely they have been heifers pregnant for the first time. 

 This is in harmony with our observations in other affected herds. 

 Abortions occur chiefly in heifers, or in cows newly introduced 

 into the herd. 



In this herd, one stable is made up almost wholly of adult 

 cows, 42 animals in all. Of these, 31, or 74%, were affected, 

 as against an average of 82.5% for the entire herd, though, in 

 arriving at this percentage for the herd, new-born heifer calves 

 were included. In this stable, where the largest percentage of 

 apparently well cows was found, abortion was virtually absent, 

 there being records of but two cases during a period of several 

 years. 



