Estimates of genetic and environmental effects on performance traits from limousin field data

Approximately 197,000 field records frm the North American Limousin Foundation performance testing program provided two major data sets and four subsets by sex for the estimation of variance components and heritabilities. The model included contemporary group, sire, breed composition of dam, age of dam and a covariate for age of calf for some traits. Heritabilities with sexes combined were: birth weight, .16 +/- .02; multiplicative age of dam corrected and age of calf adjusted 205-day weight, .08 +/- .01; age of calf adjusted 205-day weight, .10 +/- .02; additive age of dam corrected and age of calf adjusted 205-day weight, .09 +/- .01; preweaning average daily gain, .08 +/- .01; weaning weight, .09 +/- .02; preweaning relative growth, .09 +/- .01; multiplicative age of dam and age of calf adjusted 365-day weight, .14 +/- .02; age of calf adjusted 365-day weight, .16 +/- .02; postweaning average daily gain, .10 +/- .02; yearling weight, .16 +/- .02; weight per day of age, .16 +/- .02, and postweaning relative growth, .03 +/- .01. Partitioning of data sets by sex did not significantly change the estimates of heritability.