Gesundheitsmerkmale in der nachkommenprüfung auf station bei Fleckviehbullen. 2. Mitteilung: Schätzung genetischer parameter

The objective of this study was to estimate genetic parameters of health traits in German Fleckvieh bulls in progeny tests from 1994 to 2001. The veterinary records of 1775 male calves in the age from 40 to 450 days could be included in the present analysis. The genetic parameters of the incidence of bronchopneumonia, the incidence of other diseases, the number of treatments due to bronchopneumonia and the number of treatments due to other diseases were estimated using a linear multivariate animal model. The heritability of the incidence of bronchopneumonia was h ² = 0.10 and h ² = 0.28 for the number of treatments of bronchopneumonia, respectively. The corresponding estimates of the other diseases were h ² = 0.13 and h ² = 0.12. The transformation of the heritability of the incidence of bronchopneumonia and other diseases by DEMPSTER and LERNER (1950) resulted in estimates of h ² = 0.21 and h ² = 0.29. The additive genetic correlation between the incidence of bronchopneumonia and number of treatments due to bronchopneumonia were r _g = 0.86 and r _g = 0.99 for the other diseases, respectively. The additive genetic correlations among the other traits were much lower with values of r _g = 0.02 to r _g = 0.49. The residual correlations between the health traits ranged from r _e = 0.02 to r _e = 0.71. The breeding values of the sires for the incidence of bronchopneumonia varied from -0.21 to 0.24 and for the incidence of other diseases from -0.11 to 0.18. The breeding values for the number of treatments due to bronchopneumonia were between -1.94 and 3.32 and showed a larger range than the breeding values for the incidence of bronchopneumonia. Correspondingly, the breeding values for the number of treatments due to other diseases were between -0.24 and 0.35. The variation and accuracy of the breeding values of the progeny tested sires was sufficiently high to achieve a significant selection response.