A Randombred Control Population of Turkeys

Abstract

THE use of unselected control populations in the field of poultry genetics is of relatively recent advent for the study of quantitative traits. Populations of this type are needed to serve as genetic and environmental controls in order: (1) to provide benchmarks from which to measure genetic changes in populations under artificial selection and (2) to distinguish between genetic and environmental changes. Also, reliable estimates of genetic parameters, such as heritabilities and genetic and environmental correlations, are obtainable only from randombred populations; because the method of variance and covariance analysis used to estimate these parameters assumes unselected random matings. The use of control populations of chickens has been reported in the literature. Skaller (1956) used a small-sized control flock and the method of maintenance allowed inbreeding to increase 17 percent in 5 generations. This resulted in an estimated loss of 5 eggs per bird. Gowe and Johnson (1956) used a…