Excretion of calcium and phosphorus in the organism of birds (Gallus domesticus).

Excretion of 45Ca and 32P with the mixed excrements, urine and faeces, bile and pancreatic juice in male chicks and cocks has been studied, showing that: 1. Most intensified 45Ca and 32P excretion takes place during the first two days. Excretion decreases during subsequent days and on the 7th day it is insignificant. For 7 days the birds release with the mixed excrements 38.23 per cent of the intramuscularly administered 45Ca dose and 41.09 per cent of 32P. 2. Excretion of 45Ca and 32P in colostomized cocks takes place mainly through the urine and to a relatively lesser degree with the faeces. For 7 days the urinary excretion of 45Ca is 39.3 per cent, faecal excretion being 12.3 per cent. Total 32P excretion for the same period is 38.1 and 16.96 per cent of the dose introduced, respectively. 3. Cannulation of the two bile ducts (from the liver and bladder) and of the anterior pancreatic duct has shown that the endogenous faecal calcium and phosphorus originate mainly from the 45Ca and 32P with the bile and to a considerably lesser degree with the pancreatic juice. 4. The existence of an entero-hepatic calcium turnover is demonstrated by prevention of 45Ca reabsorption through cannulation of the biliary and pancreatic ducts.