Acute Metritis. 873 



uterus, and prevents to a large degree the normal involution of the 

 organ. Added to this, the interference with the retained mem- 

 branes, with a view to their removal, by laymen, empirics or 

 other incompetent persons, serves to intensify the danger of 

 infection by wounding and abrading the organ. 



In the mare, where endometritis is by far the most connnon 

 form of puerperal infection, the disease is generally attributable 

 to the fragmental retained placenta, already described on page 

 810. 



Another very fruitful cause of metritis is the introduction of 

 infection into the cavity of the organ, upon the hands, instru- 

 ments or apparatus of the veterinary obstetrist during the over- 

 coming of dystokia or other manipulations of the organ. The 

 frequency with which metritis following dystokia occurs in ani- 

 mals constitutes a severe criticism upon the usual methods em- 

 ployed by veterinary obstetrists. 



Wounds of the organ during manipulations of any kind greatly 

 facilitate the entrance into the tissues of any infection which may 

 gain admi.ssion to the uterine cavity. 



The presence of a dead fetus, which is undergoing putrid de- 

 compo.sition in the uterus, inevitably causes a more or less se- 

 rious metritis. In some instances, where the death of the fetus 

 is comparatively recent and the putrid decompo.sition has not pro- 

 gressed far, the degree of metritis maj- be comparatively unim- 

 portant, or may even pass unnoticed. In other cases, where the 

 putrid fetus has remained in the uterus for a longer period of 

 time and the decomposition has become quite complete, the in- 

 flammation of the organ is correspondingly great and serious. 

 After a long period of fetal decomposition, the uterine walls 

 may finally assume the characters and functions of absce.ss walls. 



When the fetus dies in the uterus and does not become decom- 

 posed, but undergoes mummification instead, it does not tend to 

 induce inflammation of the organ. 



Tardy involution of the uterus constantly tends to invite in- 

 fection. When the uterus does not promptly close, and its walls 

 fail to quickly come in contact with each other, there is proba- 

 bly a similar tardiness in the contraction of the vagina and vulva, 

 so that the entire tract remains somewhat freely open, inviting 

 infection. The debility of the organ, of which the tardy involu- 

 tion is but a symptom, decreases its power of resisting the infec- 



