Economic or Selection Index
|Economic or Selection Index||
Estimates the relative (not an absolute number) profit expected for the offspring of animals (reported as $/cow exposed). These are generated by assigning relative importance to economically relevant traits (ie, calving ease and calf survival, daughter longevity, weaning and yearling weights, feed efficiency, and carcass traits). Input and output prices are predicted using expected market trends and included in the overall model for offspring profitability. Economic indexes combine multiple economically important traits with predicted prices for inputs and outputs and report a single value for predicted profitability. Economic indexes have been used for decades in swine, poultry, and dairy genetic selection and have allowed these industries to make large progress in profitability. The ASA has two selection indexes, the All Purpose Index (API, designed for operations raising replacement heifers) and the Terminal Index (TI, designed for operations that will harvest all the calves).