Effects of inbreeding and selection on heritability estimates of production traits of Holstein cattle under selection

Abstract

Inbreeding and selection are forces that affect heritability, important to selection in livestock species. So, this study aims to relate those forces in a Holstein population under selection for superior milk production. Inbreeding coefficients was calculated considering 3 generations, after the individual inbreeding coefficient was calculated, inbred (7.92±2.72) and non-inbred group (0.46±0.38) were formed. The genetic variance was higher for the inbred group and for the residual variance was lower. As result, those variance changes resulted in higher heritability for all traits analyzed for the inbred group. For the levels of inbreeding observed in this study, the selection for higher productions possibly masked the effects of inbreeding.