Abstract
The initial wastages that the nutrients of rations undergo in the animal body occur in the alimentary tract. For farm animals subsisting on practical farm rations these wastages are considerable, especially for ruminants and horses that consume bulky rations containing high proportions of roughages. There are marked differences among feeds and rations in the extent to which nutritive material is lost in the digestive process, and among different species of animals differences in digestive efficiency exist. And finally among animals of the same species the completeness with which nutrients are utilised in digestion exhibits considerable variation. In a compilation of the results of digestion experiments with ruminants on American farm feeds Fraps (1925) concludes: “It is an even chance that differences in digestion of individual animals may cause variations of about 3 per cent of the productive value with corn, wheat, and a few similar feeds, about 6 per cent with the usual run of feeds, and about 14 per cent with some low-grade feeds.” Copyright © . .