796 Veterinary Obstetrics 



is favored in a quite different manner. The observations of 

 Pomayer upon this point are very exact and convincing. If 

 birth has been difficult, if the animal is weak and debilitated, or 

 if the uterus is in a debilitated state from the expulsion of the fetus, 

 retention of the fetal membranes is very probable. The expul- 

 sion of the fetus has exhausted, in these cases, the contractile 

 powers of both the uterus and the abdominal walls. In most 

 cases of parturition, there is a definite and well-marked exhausr 

 tion at the completion of the act, and a period of rest at once 

 follows. Later, when the animal system and the uterus have 

 recovered from the exhaustion of parturition, contractions of the 

 uterine and of the abdominal walls normally occur, and serve to 

 press out any remaining fetal fluids, and the afterbirth, and 

 close the uterine cavity. 



If, for any reason, the exhaustion is abnormal and the con- 

 tractions of the uterine walls do not recur promptly, infection 

 takes place very quickly. As soon as the navel cord is ruptured, 

 the fetal membranes at once cease to live, and assume the signifi- 

 cance of a foreign body. The entire mass of membranes is dead 

 tissue, filled with fluid and containing portions of the fetal 

 fluids which have uot been thrown out. Taken together, the 

 membranes and the fluids constitute a highly favorable breeding 

 ground for disease-producing organisms. Usually the broken 

 end of the navel cord hangs from the vulva, comes in cour 

 tact with bedding, feces, urine and other substances reeking in 

 micro-organismal life, and furnishes an excellent avenue along 

 which the organisms may pass into the uterine cavity. 



Still more important, in many cases, micro-organisms of the 

 most dangerous kind are introduced directly into the uterine 

 cavity on the hands of laymen, or other persons who have inter- 

 fered in cases of dystokia or have inserted their hands into the 

 uterus immediately after the expulsion of the fetus. Thus there 

 is abundant opportunity for infection of many kinds to gain 

 access to the uterine cavity and, having reached that organ, find 

 the conditions of heat, moisture, nutritive material and exclusion 

 of air ideal for their lapid and efficient multiplication. If the 

 exhaustion of the uterus continues for 10, 12 or more hours, the 

 infection of the cotyledons has probably occurred, and within 

 24-48 hours the disease processes in the cotyledons may have so 

 far advanced as to firmly incarcerate and hold the chorionic tufts. 



