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BOVINE OBSTETRICS 



Etiology. — Mummification occurs after death of the fcetus 

 only under following conditions : 1. When the air is absolutely 

 excluded. 2. When expulsion is prevented. 



The fcBtus usually dies between the fourth and sixth 

 month ; in some cases sooner, rarely later ; or at the end of 

 gestation death may be caused by interference with the circu- 

 lation, — for instance, after torsion of the uterus (torsio uteri) ; 

 then expulsion is also prevented (Franck). But diseases of 

 the fcetus and disturbances in the composition of the blood 

 may cause intra-uterine death of the fcetus. Besides torsio 



9 



Fig. 17. — Lithopsedion. 



uteri, other disturbances making expulsion impossible, may be 

 auxiliaries, obliteration of the os uteri, wanting labor pains due 

 to fatty metamorphosis of the uterine muscle, adhesions of the 

 walls of the uterus with adjoining organs, in consequence of 

 which the contractions cannot exert their expelling powers. 

 Torsio uteri is the most frequent cause. Many mummified 

 calves have distinct parallel grooves on their surface from the 

 folds of the twisted uterus (Franck). In extra-uterine preg- 

 nancy, lithopsedions may also form. (See "Extra-Uterine 

 Pregnancy.") 



