GALL STONES IN SWINE. 



Characters. The calculi are spherical, rough or ou their 

 opposed surfaces flat, clear aud glisteuing where they have be- 

 come polished by frictiou. Tliey are found as a fine sand or as 

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

 density (1303 to 1484). 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. 



GALL 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 cliemical 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 tlie right hypochondrium would indicate 

 the source of the colic. A pre-exi.sting and concurrent catarrh of 

 the bowels corroborates these indications. 



Cadeac explains that tlie obstructing calculus is called on to 

 resist the impulse 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 pulmonarj' capillaries, with the natural results of 

 increasing tension of the pulmonary artery and right heart, and 



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