Diagnosis of the Duration of Pregnancy 131 



may be rendered very exact. Thus when a cow or mare has 

 been bred but twice with an interval of two to four months 

 between and the two dates definitely known, the veterinarian 

 can then positively state by which service the animal is 

 pregnant. 



Depending upon the value of the animal and the skill of 

 the veterinarian, the rectal palpation of pregnant animals 

 may be made of wider use to breeders. The trained human 

 obstetrist examines his patient at intervals during her preg- 

 nancy in order to determine if all is well and, if possible, to 

 recognize any impending danger to mother or fetus. So in 

 animals there is an interesting and useful opportunity for 

 service. Thus in the cow with torsion of the uterus, to 

 which reference was made above, the statement is quite jus- 

 tified that this examination of an apparently well cow saved 

 the lives of herself and fetus. In mares and cows the pos- 

 terior presentation of the fetus is as a rule a definite peril. 

 In many instances definite assistance is required during par- 

 turition. If the presentation were known in advance, close 

 watch might be kept and veterinary aid more promptly sum- 

 moned. Perhaps one of the most striking instances where 

 the diagnosis of the presentation of the fetus would prove of 

 tremendous value to the breeder, is in the transverse or bi- 

 cornual development of the fetus in the uterus of the mare. 

 In the commonest of these, the ventral transverse presenta- 

 tion, virtually every foal is lost, since the sacrifice of its life 

 in the performance of embryotomy is essential to any hope 

 for the life of the mare. Nevertheless, the mortality in 

 mares from this presentation is appalling. When the con- 

 dition which I have described in Veterinary Obstetrics as 

 "compound rotated bicornual pregnancy" is encountered, 

 no foal or mare, so far as recorded, has emerged from the 

 ordeal alive. It seems to me that the most hopeful outlook 

 for such cases would be to diagnose them as early as mid- 

 term, and either bring about artificial delivery while the 

 fetus is yet small, or resort to Caesarian section some time 

 during the eleventh month. 



