The Availability of Phosphorus from Single and Combined Phosphates to Chicks

Abstract

STUDIES prior to 1955 on the utilization of the phosphorus in various chemical and commercial grade phosphates by the chick have been reviewed by Motzok et al. (1956). In most of the work reviewed no comparative values of the various phosphates were given. Gillis et al. (1954) developed a biological assay whereby the comparative availability of phosphorus contained in various phosphates could be measured. Differences in the quality of phosphates could readily be shown when this technique was used. However, some sources, such as soft phosphate, could not be assayed by this method because of their low availabilities. A practical diet was used to ascertain the available phosphorus in these supplements. Wilcox et al. (1954, 1955) found that soft phosphate was poorly utilized by turkey poults. The combination of dibasic calcium phosphate, U.S.P., and soft phosphate was utilized to the extent of available phosphorus contributed by each supplement when percentage…