Causes: obstruction of common bile duct, distoma, round worms, tæmiæ,
gall stones, encrustations, inflammations, tumors, cicatrices,
hydatids. Congenital absence. Ducts stand out on liver. Symptoms of
colic, icterus, bile poisoning, marasmus. Treat the causative
conditions.
This may occur in all our domestic animals except solipeds in which
latter there is no gall bladder.
_Causes._ Any serious obstruction to the discharge of the bile into the
duodenum may cause it. The presence of trematodes, nematodes, or even
tæniæ in the ducts, gall stones, incrustations, occlusion of the ducts
by inflammatory swelling, tumors of the liver or adjacent parts,
echinococcus, cysticercus, or cicatrices may be cited. Cadeac mentions a
case of congenital atresia of the bile duct in the calf. Vigney records
a case in the cow in which the greatly dilated gall bladder formed a
hernial mass in the epigastric region which was, however, easily reduced
by manipulation.
In all such cases the distended bile ducts stand out as white branching
lines on the back of the liver converging toward the portal fissure. The
walls of the ducts may be attenuated or thickened and it is alleged
calcified. They are usually lined by a deposit of cretaceous consistency
precipitated from the retained bile. The contents of the distended ducts
and bladder are variable. They may have the color (yellow, green) and
consistency of bile; they may be thick, dense and albuminous; they may
be thin and serous from inflammatory or dropsical exudation; they may be
granular, or purulent.
Though there is no gall bladder, in the soliped, a similar condition of
the biliary ducts may be produced in the same way.
According to the degree of obstruction there may be more or less acute
symptoms of biliary colic, icterus, marasmus, poisoning by bile acids,
etc.
_Treatment_ must be directed toward the removal of the special cause of
dilatation.