498 CYCLOPEDIA OF LIVE STOCK AND COMPLETE STOCK DOCTOR. 



XV. Mechanism of Parturition. 



Under normal conditions, it may be said that the pelvis itself does not 

 offer any obstacle to the passage of the fcetus, and that it is the soft parts 

 alone which oppose its exit. 



Of the different presentations we have enumerated the anterior — in 

 which the fore feet, head and chest present simultaneously — is the only 

 one we may designate as "natural," especially with the larger animals 

 and primiparae. 



Fromage de Feugre was the first to point this out, though Rainard was 

 of opinion that the posterior presentation should also be looked upon as 

 normal; Avhile Dcsplas gave Ihrec natural positions — head and fore limbs, 



STERNO-ABUOMINAL POSITION OF THE X'OETUS. 



head only, and hind limbs only ; and Del wart gives four normal positions. 

 But experience abundantly proves that the first we have described is that 

 which alone merits the designation, as it is the one in which birth can take 

 place without artificial aid. It is true that birth is possible Avhen the foal 

 or the calf presents posteriorly at the pelvic inlet ; but this is a rare presen- 

 tation, and under the most auspicious circumstances it is much less favor- 

 able and more difficult for the mother, Avhile it is very often death to the 

 young animal (especially in the mare). In the majority of cases, without 

 assistance expulsion proceeds no further than the hocks, and the foetus 

 <Iies; and even sometimes with assistance much force is necessary to deliver. 

 Whereas, in the anterior presentation, the cases are exceptional (and these 

 •liiefly in primipara?) in which even slight traction is necessary. 



