Genetic parameters for udder traits in Holstein cattle

摘要

Descriptive statistics of udder type traits of 35522 Holstein cows from 310herds are reported. Fore udder attachment, udder depth, suspensor ligament, front and rearteat placement, rear udder width and height, and teat length were scored. Genetic parameterswere estimated by multivariate analysis. Models included effect of herd, year, season of calving,evaluation code and lactation period. Heritability for teat length was 0.09 and udder depth 0.23.Genetic correlations between rear udder width and height was 0.41, fore udder attachmentand depth 0.67, front teat placement and rear teat position 0.60, rear teat placement andsuspensor ligament 0.56, and udder depth and suspensor ligament 0.42. The general means ofall traits were lower than the ideal scores but results were within the scope of previous reports.Results suggest that little response to selection could be expected from these traits.