Protein quality studies. 1. A comparison of meat and bone meal and fish meal-skim milk powder as sources of supplementary protein for growing pigs

Abstract

Pig performance was compared on wheat based diets supplemented by two levels of either meat and bone meal or fish meal plus skim milk powder. The dry matter digestibility and nitrogen retention on these diets were determined and the effect of adding zinc to diets containing meat and bone meal was examined. At the higher level, fish meal plus skim milk powder produced greater daily gains between 60-160 lb than the meat and bone meal, but feed conversion and carcase lean were not affected. At the lower level, fish meal plus skim milk powder produced leaner carcases and greater daily gains between 60-160 lb than the meat and bone meal supplement, but had no effect on feed conversion. Between 60-100 lb, feed conversion was affected by level but not by supplement, and the higher level of fish meal plus skim milk powder produced greater daily gains than all other diets. The higher levels of each supplement produced greater nitrogen retentions and leaner carcases than the lower levels. Dry matter digestibility was least on the higher level meat and bone meal. Zinc supplements had no effect on performance.