292 Surgical Diseases and Surgery of the Dog 



or develops during the first few days after birth. The ring in this 

 case is formed by a patulous condition of the omphalo-mesenteric 

 duct and the sac by the sheath of the umbilical cord covered by the 

 integument. Under normal conditions the umbilical orifice becomes 

 obliterated by fibrous organization during the first few days suc- 

 ceeding birth. When this development proceeds tardily' the em- 

 bryonic tissue in the neighborhood of the orifice gradually recedes 

 before the pressure of the viscera and a hernia is formed. The con- 

 tents consist usually of omentum alone, though sometimes large 

 intestine accompanies it. In acquired umbilical hernia of later life, 

 parietal peritoneum forms the sac. 



Symptoms and Diagnosis. This form of hernia is easily recog- 

 nized as a soft or firm tumor at the umbilicus. 



Treatment. The majority of cases of umbilical hernia among 

 newly-born puppies result in spontaneous cure, so that treatment of 

 this form is rarely necessary. Sometimes a small swelling persists 

 during life through adhesions forming between the ring, sac, and 

 omentum without complete return of the protrusion. It is a good 

 plan to apply adhesive bandages over the swelling to assist the tardy 

 closing process. Some practitioners claim to have good results 

 from the injection of a few drops of a ten per cent solution of 

 chloride of zinc. When it is necessary to treat by herniotomy the 

 best results are obtained by completely excising an elliptic portion 

 of the wall surrounding the umbilicus (omphalectomy). 



Ventral Hernia. This term comprises all hernias which arise 

 through subcutaneous disruption of the abdominal muscles. It 

 originates either traumatically or by spontaneous rupture under 

 extreme intraabdominal pressure or it may result from surgical 

 wounds. The lesion is not very common. The symptoms and 

 treatment have already been outlined. 



Inguinal Hernia in the Female, This form of hernia is most 

 common of all. It is characterized by passage of a fold of peri- 

 toneum and visceral organs through either or both inguinal canals. 

 The inguinal canal in the female is very short, and its diameter 

 varies according to the sex and conformation of the animal, being 

 more pronounced in the female than in the male. The internal ring 

 in the female is normally covered by parietal peritoneum, and con- 

 sequently sealed. 



For some unknown reason the lesion occurs more frequently 



