Index for daughters’ fertility in the Netherlands
نویسنده
چکیده
In the Netherlands a fertility index is introducing which describes the fertility of daughters of a bull. The index is based on two breeding values which are estimated for all bulls; non return after 56 days (NR56) and interval between calving and first insemination (ICI). These two traits are combined in an index: the calving interval index or CI-index. This index was developed after comparing several indexes with different traits and their effect on the trait CI, the trait considered by the farmers as most important female fertility trait
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