The digestibility of dietary protein in the ruminant

Abstract

IN studying the digestibility of food protein the normal procedure is to analyse the food for its content of N and to feed a constant amount to experimental animals. After a preliminary period of such length that the faeces can be presumed to represent the experimental ration, the faeces are collected and analysed for a period of 7-10 days. In certain experiments markers have been used to distinguish the faeces of this period from that of the preceding and following periods. The percentage of the ingested nitrogen not appearing in the faeces is called the "coefficient of digestibility of protein".