The Effect of Selection for Early Growth on the Market Grades of Turkeys

INTRODUCTION THE genetic relationships between growth at different age intervals have been explored in many species following the work of Hazel et al. (1943). Reviews of several of these studies in turkeys have been included in the papers of Johnson and Gowe (1962) and Abplanalp et al. (1963), whose investigations have included selection experiments that involved correlated responses between growth at different age intervals. Some attention has been focused on the genetic relationships between different components of turkey carcasses. One aspect of this problem is reflected in the experiments of Johnson and Gowe (1962) which allowed for a comparison of fat grades in 24 week old turkeys arising from two lines selected for growth to 12 and 24 weeks of age respectively. Histogram comparisons suggested that fattening grades were higher for the individuals of the line selected for earlier growth. The present study was undertaken with the objective of studying…