GAIvIv STONES IN SWINE. 



Characters. The calculi are spherical, rough or on their 

 opposed surfaces flat, clear and glistening where they have be- 

 come polished by friction. They are found as a fine sand or as 

 calculi the largest of which have been 75 grains, and of a high 

 density (1303 to 14S4). Bruckmiiller found that they contained 

 carbonate of lime and biliary mucus. Verheyen found biliary 

 resin, mucus, pigment, and a little fat. They are rare in fat hogs 

 in America. No diagnostic symptoms have been observed. 



GALIv STONES IN DOG AND CAT. 



These are more or less spherical, dark brownish green, and 

 usually found in the gall bladder or larger bile ducts. They may 

 vary in .size from a pea to a hazel nut. Their chemical analysis 

 is wanting. 



Symptoms. There may be evidence of biliary obstruction and 

 if this occurs intermittently and is associated with colic, it becomes 

 somewhat characteristic. Constipation, emesis, icterus, and 

 sometimes tenderness of the right hypochondrium would indicate 

 the source of the colic. A pre-existing and concurrent catarrh of 

 the bowels corroborates these indications. 



Cadeac explains that the obstructing calculus is called on to 

 resi.st the impul.se of the bile forced upon it by the. spasmodic 

 contraction of the bile ducts, which distends the bile duct imme- 

 diately back of the stone to perhaps ten times its normal size. 

 Then under a suspension of the spasm or even an antiperistaltic 

 contraction of theduct, the calculus is forced back into the dilated 

 portion or even into the gall-bladder, and the attack is relieved. 

 Under repeated irritations of this kind the inflammation of the 

 bile ducts extends into the liver and determines cirrhosis. 'The 

 irritation further through the sympathetic produces a reflex con- 

 striction of the pulmonary capillaries, with the natural results of 

 increasing tension of the pulmonary artery and right heart, and 



524 



