510 Cholelithiasis. 



septicemia of umbilical origin. The name given by tliese autliors to 

 this condition is icterus gravis. 



Literature. Dieckerhoff, Spez. Path., 1004, I, loni.— Ilartmann, O. Vj., 18S0, 

 LIU, 2.— Schottler, A. f. Tk., 1898, XXIV, 297. 



2. Gallstone Disease. Cholelithiasis. 



Occurrence. Apart from precipitations and incrustations 

 in the l)ile ducts, true g'allstones are of rare occurrence. They 

 are, however, found most frequently in the horse and ox, more 

 rarely in the dog, and exceptionally in the cat, pig and sheep. 

 Kitt found a calculus in the gall bladder of a fowL 



Etiology. The most frequent cause of precipitation of the 

 hile salts is catarrh, either of the bile ducts or gall bladder. 

 The large amount of mucus secreted acts upon the bile and es- 

 pecially on the salts of the bile acids and decomposes them, 

 while a large quantity of cholesterin is added to the bile through 

 the desquamation of the epithelial cells. The cholesterin and 

 the bile pigments are held in solution by the bile acids. The 

 decomposition of the acids leads to the precipitation of the 

 cholesterin and pigments. At the same time carbonate of lime 

 is precipitated or else it is produced by the disintegration of 

 the epithelial cells shed from the diseased mucous membrane 

 (Naunyn). Partial or complete stasis of the flow of bile tends 

 to the formaton of biliary calculi, and this is also likely to 

 cause catarrhal inflammation. 



In the livers of ruminants there are frequently soft masses 

 of precipitated bile salts covering the inner surface of the bile 

 ducts to a variable thickness and also mixed with the bile. In 

 old animals these masses form hollow cylinders lining, and 

 firmly adherent to, the inner surface of the walls of the bile 

 ducts. This is frequently the case in distomatosis. On the 

 other hand, in horses it is possible that the cause is a bacterial 

 infection derived from the duodenum which leads to catarrh 

 of the bile ducts. 



In the majority of cases the starting point of a true gall- 

 stone is a mass of desquamated epithelium, mucus and bac- 

 teria, around which the precipitated bile salts and cholesterin 

 are deposited in layers, A similar part is played by dead ani- 

 mal parasites, such as flukes, or their eggs. Occasionally, the 

 starting point may be a foreign body wdiicli has passed into the 

 bile duct from the duodenum. Since stagnation of the bile 

 favors the deposition of the bile salts and thus aids bacterial 

 infection, gallstones are more frequently found in animals that 

 are always stabled or move about but little. 



Anatomical Changes. In the horse and ox the bile ducts 

 sometimes contain hard cones or cylinders wdiich may be as 

 thick as a finger. In the fresh state they are light or dark 



