Summary: | The aim of this study was to estimate the heritability of claw conformation traits in Slovak Holstein cattle by using two approaches: the Bayesian method and the restricted maximum likelihood (REML) algorithm. Overall 860 claw trimming records of 716 dairy cows were included in this study. The claw morphometric data were collected after functional trimming between 2012 and 2017. The conformation of claws was evaluated based on eight parameters (angle, length, heel depth, height, diagonal, width, total and functional areas) by digital image analysis and NIS Elements 3.0 software. The heritability of those traits was estimated using a single trait animal model including fixed effects of herd-year-season, stage of lactation and sire. Both of applied approaches indicated low or moderate level of heritability across analysed traits, in average 0.28 ±0.08 (REML) resp. 0.22 ±0.09 (Bayesian). The highest heritability was found for diagonal of claw (0.41), while the lowest one was observed for the total area of claw (0.18) and the claw height (0.12) based on the REML algorithm and Bayesian approach, respectively. The study confirmed previous assumption that the claw conformation traits are inherited in low or moderate mode. Future analysis of genetic correlations between them can be beneficial for construction of new selection indices, better responding to today’s welfare requests and use of new generation indicators made possible.
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