Relationship between fertility traits and 305 days milk yield
1997
Huba, J. | Peskovicova, D. | Chrenek, J. | Kmet, J.
Fertility traits were analysed in 5500 first-calf dual-purpose cows and milk types of cattle. The model of covariance analysis contained fixed effects of herd, year of calving, and genotype group; concominant variables were days to first service and milk production for 305 days lactation. Estimates of regression coefficients between fertility traits and milk production are given in Tables I and II. All linear regression coefficients in both production types were statistically highly significant (P less than 0.01) except gestation period. A negative regression coefficient was found in percentage of gestation after 1st insemination, i.e. higher production is linked to poorer gestation. Positive regression coefficients in other parameters point out that higher producing dairy cows have a longer service period between calving and need more inseminations for gestation. These results accord with the findings of some authors
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