Etiology. 573 



to the entrance of infective material. Violent blows with blunt 

 objects are likely to set up at most a circumscribed perito- 

 nitis only. Besides accidental wounds of the abdominal wall, 

 those made in the course of operations play an important part 

 in the production of peritonitis. Among these may be men- 

 tioned laparotomy, operation for hernia, castration, etc. Sim- 

 ple puncture carried out with all precautions as to asepsis is 

 far less dangerous. Horses are particularly susceptible to in- 

 fection in this way and this fact is no doubt associated closely 

 with the high degree of susceptibility that horses, as a rule, 

 show to the pyogenic bacteria. 



Injury to any of the abdominal viscera, the contents of 

 which are not germ free, is exceedingly likely to set up peri- 

 tonitis. In cattle foreign bodies are a very common cause of 

 peritonitis, but cases of this sort are far more rare in other 

 species of animals, although, of course, foreign bodies accident- 

 ally swallowed may cause perforation of the stomach or intes- 

 tine. Included among such cases must be mentioned rupture of 

 the rectum during rectal examination, the administration of a 

 clyster, or copulation. Rupture of the vagina or uterus during 

 dystocia and especially as a result of surgical interference, rup- 

 ture of the oviduct in birds, rupture of the bladder in cases of 

 retention of urine or perforation during passage of a catheter, 

 rupture of diseased gall bladders, etc., may all be causes of peri- 

 tonitis. Rupture of the stomach or intestine resulting from ul- 

 ceration or excessive distension, or more rarely from traumatic 

 causes, sets up peritonitis of the same type (peritonitis per- 

 forativa). 



Peritonitis may also follow rupture of the other abdominal 

 viscera if these be the subject of a pre-existing bacterial disease. 

 From various causes (strangles, foreign bodies, animal para- 

 sites) there may be suppuration of the liver, spleen, prostate, 

 testicle, spermatic cord, and the walls of these abscesses may 

 burst. In cases of puerperal metritis there may be pus in the 

 Fallopian tubes and rupture of the uterus permits of easy infec- 

 tion of the peritoneum. According to Lignieres the streptococ- 

 cus albus and aureus do not rarely occur in a healthy uterus. 



In bacterial inflammations of the abdominal organs the in- 

 flammatory process may extend to the peritoneum without there 

 being any rupture of a viscus, the infection reaching the peri- 

 toneum either directly or by way of the Ijanph stream. In this 

 connection deep-seated inflammation of the stomach, intestine 

 and interior of the bladder or sexual organs are most danger- 

 ous. In severe intestinal disorders the bacteria reach the peri- 

 toneum either by multiplying in the diseased wall of the intes- 

 tine until they reach the serous coat, or they escape in the ex- 

 travasated serum. 



Boiigartz frequently ob!-erve<l jjeritonitis in cows newly brought into cow 

 houses and thouglit that it was connected with active fermentation processes in the 

 intestine, the products of the fermentation favoring the passage of the bacteria 

 through the intestinal wall. 



