Extracted herbage leaf protein for poultry feeding II. The use of leaf protein in chick rations

Abstract

1. Two live-weight gain experiments using dayold chicks are described. A mash containing a basic ration with leaf protein was compared with a control mash containing the basic ration plus fish meal.2. Details of the source of the leaf protein, its extraction and chemical analysis are given.3. The composition and analyses of the mashes are recorded, together with their rate of feeding.4. The live-weight gains at fortnightly intervals are discussed and the results adjusted for sex of chicks, weight at day-old and level of protein in the mash.5. In the first experiment some of the pullets from each treatment were fed on a commercial growers' ration from 6 weeks old to maturity.6. The birds on both treatments in the two experiments were equally healthy. The mortality rates were normal. The leaf-protein chicks had deep yellow pigmentation.7. The results of the experiments are compared. In the first the leaf-protein mash was as valuable as the fish-meal mash; in the second experiment the fish-meal mash proved to be superior.8. A new method of measuring the biological value of the protein of herbage plants is suggested, using extracted protein fed to chicks or rats.9. It is concluded that a mash composed of homegrown cereals plus leaf protein with vitamin supplements, a balance of minerals and additional aminoacid if necessary, would be suitable for rearing chicks.