294 BOVINE PATHOLOGY. 



toneum, and, therefore, the faoces do not pass into the 

 peritoneal sac. Their entry into the wound tends to 

 prevent it from healing, and a fistula in ano or recto-vaginal 

 fistula forms. This is not very liable to take place in the 

 ox, for the faeces are pultaceous. The presence of a recto- 

 vaginal fistula gives rise to passage of fseces through the 

 vulval opening, also chronic irritation of the generative 

 passage, and the opening may be felt on exploration. 



Intestinal Parasites are comparatively rare in the ox, 

 and seldom give rise to serious disorder. The principal 

 are Ascaris lumhricoides, and various Strongyles. Tania 

 expansa is described by Law as causing serious indigestion 

 and abdominal disturbance in America, Australia, and 

 some parts of Germany. 



Intestinal Tumours are generally fatty on the peritoneal 

 surface; cancerous when projecting into the intestinal 

 tube, hsemorrhoidal when in the rectum. The effects of 

 these and of calculi have been already noticed. 



Malformation or the Intestines. — Of these proctatresia 

 or infijpervious anus is the most frequently seen in calves. 

 Sometimes the anal opening is closed by skin j in other 

 cases the anus is perfectly formed, but at a short distance 

 from the external orifice there is a membranous septum 

 separating the passage in which the meconium is situated 

 from the anus. In another form the large intestine termi- 

 nates in a cul'de-sac in the posterior part of the abdomen. 

 These latter cases are hopeless, but in either of the former 

 relief may be afforded by division of the obstructing 

 membrane by two crucial incisions. Attention is called 

 to this condition by violent straining of the young animal, 

 which has not passed fasces since birth. The first milk 

 excites the bowels to action for expulsion of the meconium, 

 but this relief is prevented. 



Mechanical Distension of the Rectum with hard pellets of 

 meconium is sometimes a cause of similar symptoms. 

 The accumulated material must be gradually removed with 

 the oiled forefinger. Sometimes the quantity present is 

 enormous. 



