Effects of Starter Protein Level on Performance and Body Composition of Pigs

Abstract

Weaned pigs were fed 10, 17, 24 or 31% crude protein diets of equal caloric content and protein quality from 4.8 to 24 kilograms. From 24 kg. they were treated similarly, being fed a 16% crude protein diet to 57 kg. and a 12% protein diet to 92 kilograms. Increasing starter protein level to 17% improved weight gains and increasing starter protein level to 24% improved feed efficiency to 24 kilograms. Chemical analysis of pigs at 24 kg. live weight showed that increasing protein level resulted in marked increases in water and protein and decreases in fat content of the carcass, and offal. During subsequent growth, pigs fed high starter protein levels were less efficient than pigs fed low starter protein. Pigs fed 10% starter protein had reduced daily feed intake from 24 to 92 kilograms. No significant treatment differences were found in conventional carcass measurements obtained at 92 kg., but there was a trend toward leaner carcasses for those pigs fed the low level of protein early in life. This was confirmed by chemical analysis of pigs fed the 10% and 31% starter protein diets. The empty body of pigs fed the 10% protein during the starter period contained significantly less fat than that of pigs fed 31% protein. Copyright © 1969. American Society of Animal Science . Copyright 1969 by American Society of Animal Science