A Comparison of Commercial Inbred-Hybrid Chickens and First Generation Crossbreds from Non-inbred Stock

IN RECENT years chickens produced by crossing inbred lines of different breeds have been distributed commercially. Such birds have been termed “inbred-hybrids”, to differentiate them from crosses of different breeds with no previous inbreeding. The growing popularity of the inbred-hybrids and the extensive breeding program required for their development make necessary critical tests of the relative performance of such stock. Knox (1946) reported high egg production from stock derived from inbred Rhode Island Red males and inbred White Leghorn females. Other stocks tested consisted chiefly of inbreds and noninbreds from the two breeds. Unfortunately, no matings were reported involving crosses of Rhode Island Red males and White Leghorn females from noninbred ancestry. Data from commercial sources suggest a considerable advantage in egg production for inbred-hybrids in comparisons with purebred stocks. Such tests give no information relative to the amount of heterosis attributable to breed crosses, and do not evaluate the . . .