Genetic parameters for claw and leg health, foot and leg conformation, and locomotion in Danish Holsteins

Abstract

The purpose of this study was to estimate the genetic correlations among claw and leg health and potential indicator traits. Claw health was defined as absence of heel horn erosion, interdigital dermatitis, interdigital phlegmon, interdigital hyperplasia, laminitis, and sole ulcer. Leg health was defined as absence of hock infection, swollen hock, and bruising. The potential indicators were locomotion and foot and leg conformation, represented by rear leg side view, rear leg rear view, foot angle, and apparent hock quality and bone structure. The study was conducted using records from 429,877 Danish Holstein cows in first lactation. Binary health traits were divided into 3 subcategories: claw health, leg health, and absence of all claw and leg disorders. Genetic (r(g)) and phenotypic correlations were estimated using a bivariate linear sire model and REML. Estimated heritabilities were 0.01 for all 3 combined claw and leg health traits (on the observed binary scale), 0.09 for locomotion, 0.14 for rear leg rear view, 0.19 for rear leg side view, 0.13 for foot angle, 0.22 for apparent hock quality, and 0.27 for apparent bone structure. Heritabilities were 0.06 and 0.01 for claw health and leg health, respectively, when transformed to the underlying continuous scale. Claw and leg disorders are an increasing problem for Danish Holsteins, but genetic improvement of claw and leg health is challenging because the traits have low heritabilities. Claw and leg health were separate but correlated traits (r(g) = 0.35). Locomotion and rear leg rear view were useful indicator traits for claw health (r(g) = 0.46 and r(g) = 0.21, respectively), whereas hock quality and bone structure were useful indicators for leg health (r(g) = 0.42 and 0.26, respectively). Claw and leg health should be considered as separate traits in genetic evaluations that also include the useful indicator traits to compensate for low heritability of the health traits.

Genetic correlations between production and disease traits during first lactation in Holstein cows

“…The overall frequency of CLD (2.0%) was much lower than that in Danish Holstein cows (6.3%; Laursen et al, 2009). The Danish CLD data were recorded by veterinarians, whereas those in our study were reported by the cows' owners.…”

“…Estimated heritabilities are less than 0.15 for mastitis (e.g. Harder et al, 2006;Pérez-Cabal et al, 2009;Hinrichs et al, 2011) and 0.12 for CLDs (Koenig et al, 2005;van der Waaij et al, 2005;Onyiro et al, 2008;Laursen et al, 2009;Buch et al, 2011). However, next to production and fertility traits, health traits are still important in national breeding schemes, because even a small increment in disease rates has a serious influence on farm management costs (Koenig et al, 2005).…”

Genetic parameters for production, health, fertility and longevity traits in dairy cows

“…Relatively, high genetic correlations between parities are likely to raise heritability estimates in multivariate analyses. In similar studies, the heritability estimates for lameness, using linear models, have been reported as low (1% to 2%; Kadarmideen et al, 2000;Laursen et al, 2009;Haile-Mariam and Goddard, 2010). In general, low heritability is common for functional traits, such as health and fertility.…”

Profile and genetic parameters of dairy cattle locomotion score and lameness across lactation

“…Heritability estimates of locomotion scores either for diagnosing lameness (Van Dorp et al, 2004) or as a linear trait assessed as part of a linear type classification scheme Laursen et al, 2009;van der Linde et al, 2010) range from 0.05 to 0.14. Heritability of lameness itself has been estimated to range from 0.07 to 0.10 (Boettcher et al, 1998;Pryce et al, 1999;Zwald et al, 2004).…”