172 BOVINE OBSTETKICS 



future parturitions. The relative dimensions of the bovine 

 pelvis already at an age of three years possess much n?.ore 

 favorable proportion for birth, when nutritious food rich in 

 lime salts has been fed. 



Therapeutics. — It is desirable to prepare as much as pos- 

 sible the dilatation of the parturient passages, so matters may 

 not be made worse by disturbances of the soft parts, as, for 

 instance, insufficient opening of the cervix uteri. The amount 

 of traction which may be applied must not exceed the force 

 developed by three men at the utmost. In an anterior position, 

 with the head resting upon the fore legs, alternate traction may 

 be exerted upon them to get the shoulders out of the way and 

 thus decrease the bicostal diameter. When half of the calf is 

 born, its trochanteric diameter is rendered parallel with the 

 vertical diameter of the pelvis, by rotating the calf on its side. 

 On a posterior presentation, with the hind legs in the genital 

 passage, the trochanteric diameter of the ealf is made to enter 

 the pelvic inlet obliquely, its passage being assisted by alter- 

 nately pulling on the hind legs, thus decreasing the distance 

 between the calf's trochanters. See also page 186. 



Unilateral or bilateral depression of the sacrum causes nar- 

 rowness of the pelvic cavity. Stockfleth describes a case where 

 the displaced wings of the sacrum and the posterior iliac spine 

 had become united by strong connective tissue. In bilateral 

 depression or complete sacro-iliac laxation, the height and 

 width of the pelvic inlet decrease. An irregular callus follow- 

 ing a fracture may also lessen pelvic dimensions. The most 

 important fractures are : Fracture of the internal angle of the 

 ilium and subsequent unilateral displacement of the sacrum ; 

 fracture of the posterior angle of the ilium and fracture through 

 the symphysis. Exostoses also may lead to constriction of the 

 pelvis. The rachitic pelvis of a two year old heifer greatly 

 resembles the juvenile pelvis ; the distance between the coty- 

 loid cavities is diminished. These abnormalities of the pelvis 

 may seriously interfere with the act of parturition, but they are 

 rare in the cow. This is due to the fact that cows with such 

 abnormalities are rarely bred and are usually rather slaughtered 



