Serum aminotransferase activities and plasma free amino acid concentrations as criteria for pyridoxine nutritional status of chicks

Abstract

1. A combination of balance and isotope techniques has been used to study the effects of dietary supplements of NH4Cl, given for 1 and 10 weeks, on calcium metabolism in 1- and 2-year-old wethers. 2. The main effects of the NH4C1 supplements were to decrease urinary pH, increase urinary Ca excretion and to increase Ca absorption and the percentage of dietary Ca absorbed. 3. The results were different from those obtained by other workers in man and rat, and possible explanations of this difference are discussed. 4. A difference was also found between 1- and 2-year-old animals in their long-term response to the NH4Cl supplement. This difference may have been due to a lack of available Ca in the diet of the younger animals, and prolonged ingestion of NH4C1 may increase the amounts of Ca absorbed and retained.