General and Specific Combining Ability for 154-day Weight Among Three-Line Crosses in Swine

Abstract

Experience in developing inbred lines of swine indicates that selection is usually not completely effective in preventing some deterioration in litter size, vigor and other components of performance Craft (1953) summarized a number of studies indicating the inbreeding depression is repaired with the first generation of outcrossing. In general, the traits which deteriorate most with inbreeding respond most definitely to outcrossing. In many cases crosses of selected lines have given results superior to non-inbred stocks.