Genetic Parameters for Digital Dermatitis and Correlations with Locomotion, Production, Fertility Traits, and Longevity in Holstein-Friesian Dairy Cows

Abstract

Heritability of digital dermatitis (DD) and correlations between DD and type traits related to legs and feet were estimated from a linear animal model. Data comprised 93,391 national type evaluation records of pedigreed first-lactation Holstein-Friesian cows that calved from 2002 through 2006. At the time of classification, cows were housed in different housing systems (i.e., cubicles, straw yards, slatted or loafing yards) and on pasture. The type traits evaluated were locomotion score (LOCO), rear legs side view (RLS), foot angle (FA), bone quality and leg and feet composite (L&F). In addition, cows were examined for DD lesions at classification. The relationships among these type traits, lifespan (LS), production (milk and fat), fertility (calving interval and 56-d nonreturn) and DD were examined by estimating the approximate genetic correlations from sire estimated breeding values. The study also evaluated the association between DD and the housing systems as well as the general conditions of the farm flooring where classification took place. In general, cows on pasture were less susceptible to DD than cows in other housing systems, whereas the association between DD and the flooring conditions was counterintuitive. Heritability estimate for DD was 0.011 on the 0/1 scale, which is equivalent to 0.029 on the assumed underlying normally distributed scale. Bone quality, LOCO, and L&F had moderate to high negative genetic correlations with DD, indicating that flatter, more refined bones, higher LOCO, and better L&F were associated with less incidence of DD. The genetic correlations between DD, RLS, and FA were not significantly different from zero. Digital dermatitis had moderate but negative genetic correlations with LS and milk and fat, suggesting that breeding for resistance to DD will result in an increase in both longevity and production. Cows affected with DD had a slightly shorter calving interval than healthy cows, an association found to be mediated through the reduced milk yield of these cows. Generally, the type traits included in this study had low genetic correlations with production and fertility traits whereas the associations between these traits and LS ranged from moderate to high. This indicates that good locomotion, straighter RLS, steeper FA, better L&F, and flatter, more refined bones are associated with increased longevity.

The relationship between fertility and intermediate optimum type traits in Polish Holstein-Friesian cows

“…The positive correlation of rear legs with ICF and negative with DO implied a shorter service period, which might be confirmed by the positive, favourable correlation between rear legs and NRc. These results partly agree with the findings of Zink et al (2011), who reported a positive genetic correlation between rear legs and both ICF and DO, but differ from the values published by Onyiro et al (2008), who obtained low negative correlations between rear legs and calving interval (CI) (0.09) and NRc (-0.11). CI and DO were closely related to each other because CI consisted of days open (DO) and gestation length and the latter showed very little variation (Jagusiak, 2005b).…”

“…The correlations of foot angle with ICF and DO reported by Zink et al (2011) were very low, whereas Onyiro et al (2008) obtained a positive and also unfavourable genetic correlation of foot angle with CI (0.19) and a favourable correlation with NRc (0.14). The genetic correlation between body depth and NRc was negative and moderate; this means that daughters of bulls with a higher breeding value for body depth were also supposed to have a worse NRc.…”

Genetic association between longevity and linear type traits of Holstein cows

“…This decrease can be explained by the increase in involuntary culling due to illnesses related to feet and legs. Onyiro et al (2008) found moderate genetic correlation with bone quality (-0.21) and high correlation between the side view of rear legs (-0.63) and digital dermatitis, reporting that cows without disease had good quality, flat bones and good set of the legs and feet, this being associated with increased herd longevity.…”

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

“…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).…”