DYSTOKIA FROM MULTIPAniTV 



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quent, is ordinarily due to malposition of the second footus ; and this 

 cause of dystokia is one which nearly always demands the attention of 

 the veterinary obstetrist. 



This malposition of the single foetus will be noticed presently ; we 

 have now to consider diiVicult birth due to multiparity. Dystokia from 

 this cause always happens when the two fcetuses are about the same 

 distance from the os uteri, and both present together at the pelvic 

 inlet ; the uterine contractions carry them simultaneously into the 

 opening, but of course they cannot possibly pass through the canal 

 at the same time ; hence the dilliculty in birth — a ditliculty which 

 varies according to the relative situation of the two foetuses to each 

 other. 



The fcetuses may be so situated that when the hand is introduced 

 into the vagina or os, it will either encounter the head of one ftt'tus 



Fig. 124. 

 Twin ForrusEs, in Dikkerkxt Puesestatioxs, passino into the (Jenital Canal. 



with the fore-limbs of the other ; four anterior or posterior limbsj two 

 hind and two fore limbs (Fig. 124) ; two, four, or six feet ; a headland 

 a tail, etc. 



The cause of this malposition is in all probability due to the relative 

 smallness of the twins, and the changes which occur in their position 

 during birth ; and it will be apparent that the obstetrist must, in some 

 cases at least, find it difficult to distinguish between such presenta- 

 tions of twins and some of the monstrosities or deformities we have 

 described. 



Diagnosis. 



In such cases the obstetrist has to ascertain : 



1. Whether individual twins are present ; 2. To distinguish, among 



