The Zinc Content of Bile and Pancreatic Juice in Zinc-Deficient Swine

Abstract

The content of Zn, Mg, Ca, bilirubin and bile acids was determined in the hepatic bile of Zn-deficient and control swine. Zn deficiency was produced by dietary Zn restriction while pair fed Zn supplemented animals served as controls for observations of hepatobiliary functions. Pigs weighing 5 kg were placed in 2 groups and fed the respective diets for 6 wk; hair and skin abnormalities as well as decreased weight gain were present in the Zn-deficient group by this time. Hepatic bile and pancreatic juice were obtained from each animal after careful isolation and cannulation of the pancreatic and bile ducts. Animals were studied for 3 h while under constant secretin stimulation and chloralose anesthesia. During this period, there was a progressive decrease in the biliary concentrations of bilirubin, bile acids and Mg in the bile of both groups, while Zn and Ca levels were not altered. The Zn concentrations in pancreatic juice were reduced in the Zn-deficient animals. The Zn content of the serum, liver, kidney and pancreas was also decreased in this group. The Ca and Mg content of the serum and organs was similar in the 2 groups with the exception of decreased Mg in the kidney of the Zn-deficient pigs. Low content of Zn in the liver and serum of the deficient animals was associated with a Zn concentration in the bile comparable to the control group; however, the relative content of Zn in pancreatic secretion and bile was altered in Zn deficiency. In control animals 60% of the Zn is in the pancreatic secretion and 40% in the bile. These percentages are reversed in the Zn-deficient animals in which 60% of the Zn is derived from the bile.