EFFECT OF SELECTION FOR LEAN GROWTH RATE UPON FEED UTILIZATION BY THE MARKET HOG

Publisher Website
Google Scholar
Abstract
Results from an individual feeding trial comparing the feedlot and carcass performance of pigs from two populations, an index selected line and a genetic control, are described. The populations were initiated in 1961, the select line restructured in 1972, and the present evaluation made on progeny born in 1976. The index was based on two traits, growth rate and backfat. Feedlot data for 123 pigs indicated a direct genetic response of.94 standard deviation units (SDU) for rate of feedlot gain and correlated responses of −1.07 SDU for days on test, −1.22 SDU for total feed required and −1.07 SDU for feed/gain ratio. Carcass data for 96 pigs indicated a direct genetic response of −1.51 SDU for average backfat and a correlated response of 1.21 SDU for carcass index. In economic terms (1976 values), the improvement in carcass merit represented an increased revenue of $3.04 per pig, the increased growth rate was equivalent to a 10% reduction in the fixed costs and non-feed variable costs per pig, and the correlated response in feed requirements reduced feed costs by $3.13 per pig. Practical implications in respect of pig testing programs are discussed.

This publication has 1 reference indexed in Scilit: