Anotace:
The study aimed to analyse the claw formation traits in a selected population of Holstein and Slovak Spotted breeds and estimated their heritability and genetic correlation using linear mixed models. Images of the right hind claw were taken during functional claw trimming. NIS Elements 3.0 and MS Excel were used to analyse the images and prepare a database of phenotypic information. Pedigree information of animals was processed using the CFC program. Basic statistical analysis of the variability studied traits was estimated using SAS Enterprise Guide v7.1. Genetic correlation and heritability were estimated using the R package MCMC glmm. Lower average values of claw formation were found for the evaluated Holstein dairy cows compared to the evaluated group of Slovak Spotted dairy cows. The following effects (fixed effects) sire, date of birth, lactation order, calving year, calving season, the season of the claw trimming, and year of claw trimming were evaluated. Both positive and negative genetic correlations were observed between the claw conformation traits in the evaluated dairy cows. In the case of the Holstein breed, the highest positive genetic correlation was found for claw length and diagonal (0.91) and in Slovak Spotted cows for claw width and functional claw area (0.87). Claw conformation traits are generally low heritable, with an average h2 value of 0.30±0.09.