The amino-acid requirement of laying hens

Abstract

T h e objectives of previous studies from this laboratory were to develop a diet in which nitrogen was supplied as free amino-acids that would maintain egg production (Fisher & Johnson, 1956) and to determine those amino-acids essential for it (Johnson & Fisher, 1956). In proceeding with the determination of the requirement for individual amino-acids it was necessary, in order to reduce all amino-acids to minimal levels, to consider the factors that influence the amino-acid requirement of a species.