482 Veterinary Obstetrics 



the first 60 days of pregnancy, but, running in pasture as they 

 were, the fetuses would not be discovered, and would probably 

 be picked up by scavenger animals or birds. The mares would 

 show no signs of any accident having occurred, so that it was 

 only later, when a few fetuses had become sufficiently large to be 

 noticeable, that the true character of the interruption in breed- 

 ing was discernible. 



In other instances we have noted the disease occurring during 

 the late summer and early autumn, when the mares had been 

 pregnant from four to six months. In these outbreaks the dis- 

 ease was quite as virulent as in those outbreaks occurring during 

 the nth month of gestation'. Man)- authors claim that abortion 

 in the mare is more common as gestation nears its end. This 

 difference, if it exists, is not so great as it seems, because the ac- 

 cident in the earlier stages of gestation is largely overlooked and 

 passes unseen. 



The symptoms of infectious abortion in the mare depend 

 very largely upon the stage of gestation at which the disease ap- 

 pears. It passes virtually unnoticed during the earlier stages of 

 pregnancy. During the first eight weeks of gestation it is usually 

 by mere chance that abortion is discovered. In one case which 

 we observed, a mare was being driven when the driver noticed 

 some object protruding from the vaginia. Upon examination, 

 this was found to be a fetus about 4 inches in length, enclosed in 

 its membranes. Such a fetus is readily overlooked, and its ex- 

 pulsion was discovered only because the aninial was being driven 

 at the time. Even then it might readily have dropped out 

 upon the road without being observed at all. L,ater in preg- 

 nancy there may occur slight symptoms of impending abortion 

 for a few hours, or possibly a day, before the expulsion of the 

 fetus. These symptoms consist essentially of some swelling of 

 the .vulva, with a more or less conspicuous muco-purulent dis- 

 charge. Later, according to the period of gestation, there may 

 be more or less prominent labor pains, with light symptoms of 

 colic, a few hours prior to the expulsion of the fetus. 



Even in the more advanced stages of pregnancy, however, abor- 

 tion usually occurs without forewarning and the first evidence of 

 anything amiss, so far as the owner observes, is finding the dead 

 fetus in the stable or pasture. 



