700 



Veterinary Obstetrics 



the torsion is but slight, it does not interfere seriously with the 

 circulation of the uterus and the nutrition of the fetus. The con- 

 tractile power of the uterine walls remains essentially intact, and 

 the life of the fetus may not be threatened except by delay in its 

 expulsion, caused by the narrowing of the birth canal, owing to 

 the partial revolution of the organ. In such slight cases the 

 torsion merely constitutes a mechanical impediment to partu- 

 rition, which, if not relieved, may finally end in the death of the 

 fetus, to be followed by the ordinary consequences of fetal death 

 and decomposition. Such mild cases are recorded, but have not 

 been seen by us. 



When the torsion is extensive, it directly interferes with the 

 circulation in the uterus, and secondarily with the nutrition of 

 the fetus. As shown in Figs. 114-116, whenever the uterus re- 

 volves upon its long axis all the blood vessels become more or 

 less incarcerated, so that the circulation is very promptly dis- 

 turbed or may be completely cut off. This applies equally to 

 vessels arising from the pudic or ovarian vessels. As soon as the 

 circulation is disturbed, the effect upon the uterus is more or less 



01 



Fk;. 117. T..KhH)x -I 



V, Vagina. OE, Os uteri externum. 

 BL, Broad ligament. C. Cotyledon. 



01, Os uteri internum. 

 U, Uterine cavity. 



