E. ANOMALIES AND DISEASES OF THE FETAL MEM- 

 BRANES AND OF THE UMBILIC CORD. 



1. Dense Chorion. It has been asserted that the fetal mem- 

 branes may be abnormally thick and resistant in one case or 

 abnormally thin and weak in another, and that these may result 

 in more or less danger to the mother or fetus. As a .source of 

 dystokia, onlj- the abnormally thick and resistant membranes, 

 the chorion, can produce any serious results. How frequently 

 these abnormalties occur in veterinary obstetrics cannot be de- 

 termined. We have found no records of cases where such a condi- 

 tion was clearly proven. The toughness of the chorion or other 

 membrane must be merely comparative, and its existence will 

 largely depend upon the interpetration of the obstetrist in attend- 

 ance. Should it occur, artificial rupture or incision is demanded. 



2. Adhesions of the Fetal Membranes to the Fetus. 

 Very rarely in veterinary obstetrics there are found adhesions 

 between the fetal membranes and the fetus, which tend to in- 

 terfere with birth. There is no part of the fetus upon which 

 such adhesions may not occur. All the membranes may be in- 

 volved — amnion, allantois and chorion — and cause more or less 

 firm adhesions with the fetus, and may also extend to and involve 

 the uterine walls. Fleming cites one instance where the adhe- 

 sion took place upon the frontal region, and interfered with the 

 expulsion of the calf. In other cases the adhesion has occurred 

 upon the skin of the pastern and elsewhere. When such adhe- 

 sions exist, and result in dystokia, they must be divided in order 

 to bring about prompt delivery. 



3. Hydramnois and hydrallantois. On page 424 we have 

 already described the dropsies of the fetal membranes as causing 

 more or less serious interference with the well-being of the 

 mother during gestation, and have there discussed the action 

 necessary to be taken in these cases. 



4. Abnormalities of the Umbilic Cord. The umbilic cord 

 of domestic animals is very rarely of an abnormal character, 

 either in dimensions or in its tissue. It varies greatly, as we have 

 already noted on page 364, in its length in various domestic ani- 

 mals, but we are unaware that these variations in length have 

 any special significance to the obstetrist. If very short, it natur- 

 ally must rupture very early, perhaps before the fetus is completely 



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