54 8 Diseases of the Genital Organs 



uterus contains no notable exudate. The time occupied by 

 the visible act of parturition is fifteen to thirty minutes of 

 definite expulsive effort, during which the calf is born, fol- 

 lowed immediately by a period of one to two hours during 

 which uterine involution progresses rapidly and the fetal 

 membranes passively separate from the placental areas and 

 are then expelled by the contractions of the uterus. There is 

 an active and tonic elimination of the vast uterine cavity 

 which existed an hour or two before. There is no place 

 within the uterine cavity for the retention of recognizable 

 masses of blood or other matter, and the contraction of the 

 uterine walls inhibits hemorrhage from its mucosa or the 

 outflow of recognizable quantities of lymph. 



When active infection is present in the utero-chorionic 

 cavity of the pregnant animal, the parturition is tardy. The 

 expulsion of the fetus may require five, ten or many more 

 hours. Dystocia may occur as a result of uterine paresis 

 and necessitate aid. After the fetus has been expelled, the 

 dehiscence of the fetal membranes is slow and uncertain 

 and uterine involution is tardy and feeble. Then follows an 

 exudate into the uterine cavity (or into the utero-chorionic 

 cavity if the fetal membranes are retained) which tends to 

 reveal its presence by becoming discharged from the vulva. 

 The exudate may, however, be detained in the uterus for 

 several days and may be resorbed without any notable part 

 of it having appeared externally. 



When the discharge appears or for other reasons a clini- 

 cal examination is made,' the scarlet-gray exudate already 

 described may be found in the vagina or uterus or both. It* 

 the uterus largely retains its tone, the exudate is nearly all 

 forced out into the vagina promptly instead of accumulating 

 within the uterine cavity. From one-fourth to one pint may 

 accumulate in the cervical end of the vagina. If the uterus 

 is very paretic, up to one gallon or more of the exudate may 

 accumulate in the cavity while the vagina may be free of 

 any notable amount. Then the exudate may not be expelled 

 actively, but be forced out passively when the animal is re- 

 cumbent, owing to the mechanical pressure of contiguous 



