Utnbi/ic Hernia 1049 



the abdominal cavity, rendering the hernial ring easily recog- 

 nizable by palpation. Usually there is no pain upon pressure or 

 manipulation. If the young animal is turned upon its back, 

 the tumor usually disappears spontaneously. If the animal is 

 caused to struggle, or its nostrils be closed for a time so as to 

 cause severe respirator}' effort, or it is made to cough, the hernia 

 temporarily increases in size. 



In some cases the intestine occupying the hernial sac may 

 contain hard, firm masses of feces, which render the hernia hard 

 and firm. Such fecal matter is not readily pushed through 

 the ring into the abdominal cavity. 



The contents of the hernia may become incarcerated or strangu- 

 lated, and induce thereby symptoms differing very materially 

 from those which have already been described. If the hernial 

 contents consist of intestines, and strangulation occurs, the 

 tumor at once becomes very tense and hard, and is more or less 

 enlarged as compared with its previous condition, and the animal 

 shows severe pain, expressed by violent colic. The hernia may 

 also be sensitive to the touch. 



When the hernial contents consist of omentum, and it becomes 

 incarcerated, the tumor becomes tense and indolent, cannot be 

 reduced, and induces no pain upon palpation. 



Diagnosis. Though umbilic hernia is not liable to become 

 mistaken for other diseases, it should be borne in mind that there 

 are possibilities of error in diagnosis. In one instance we at- 

 tended an umbilic hernia complicated by the presence of umbilic 

 fistula from infection at the time of birth. The enlargement 

 present was attributed to the chronic infection alone. In opening 

 the fistula we punctured the peritoneal wall of a small hernial 

 sac, and caused a prolapse of the omentum. Abscesses may 

 occur at the navel as a result of infection, and may lead to diag- 

 nosis of hernia, but the abscess is irreducible, and may readily be 

 tested, in cases of doubt, by aspirating with a hypodermic syringe. 

 It is virtually impossible to differentiate between an uncompli- 

 cated hernia of the intestines and hernia of the omentum ; nor is 

 the differentiation of any great practical value. Strangulated 

 umbilic hernia of the intestines is recognized by the hernial colic, 

 the irreducibility of the hernia, and the firm, hard character of 

 the tumor. Incarcerated umbilic hernia of the omentum, occur- 



