The nutritive value of fish meal, meat‐and‐bone meal and field bean meal as measured by digestibility experiments on the adult colostomised fowl

Publisher Website
Google Scholar
Abstract
Digestibility experiments were carried out, using colostomised hens fed semi‐synthetic diets containing fish meal, meat‐and‐bone meal or field bean meal as the sole source of protein. A “nitrogen‐free” diet was fed to one group of three birds. Metabolic faecal nitrogen (MFN) output of birds consuming about 75 g dry matter/d was 106 mg/d. The amino acid composition of the MFN was determined. Endogenous urinary nitrogen output (one result) was 0.80 mg Wg0–75/d. The true digestibilities of the crude protein of fish meal, meat‐and‐bone meal and field bean meal were respectively 89, 69 and 83 per cent. Digestibility coefficients of individual amino acids were also determined and it was found that the amino acids were not equally digestible. However, for each protein source most of the coefficients fell within a range of + 5 per cent of the mean. The metabolisable energy content of the fish meal was 2645 kcal/kg, meat‐and‐bone meal 1988 kcal/kg and field beans 2910 kcal/kg.