Heritability Estimates and Genetic Correlations Among Several Traits in a Meat-Type Poultry Population ,

THERE are many published estimates of the heritabilities of economic traits in chickens. With the exception of early body weight, most estimates have been obtained from production lines or crosses. There are considerably fewer published estimates of genetic correlations among economic traits, particularly estimates from meat-type lines or crosses. Methods of estimating heritability and the possible biases associated with the various methods have been discussed by Lush (1948), Lerner (1950 Lerner (1958), Falconer (1960), and others. The methods which have been commonly used to estimate the heritability of traits in poultry are the paternal or maternal half-sib correlation, full-sib correlation, and the regression of offspring on parent. The estimates of additive genetic variance and/or phenotypic variance may be biased by the following: a. genotype environment interactions b. dominance variance c. epistatic variance d. maternal effects e. selection of sires or dams f. non-random mating g. sources of non-genetic variation other than…