Page 4 - C-B Charolais Annual Production Sale Bulls Heifers Red Angus-X– March 27, 2018
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Terminal Sire Index

        The AICA Terminal Sire Index (TSI) utilizes economic
        and management descriptions of your ranching
        operation, along with EPD on available Charolais bulls
        to assist in identifying the most profi table sires for
        your unique operation. Using economic selection index
        theory, this tool will generate dollar indexes per terminal
        progeny produced on bulls in the AICA database, ranking
        them for profi t potential given the inputs you provide.
        The dollar indexes are to be interpreted much like single
        trait EPD. For example, if sire A’s index is $191.66 and
        sire B’s index is $200.00, then we would expect Sire B’s
        offspring to average $8.34 more net return ($200.00 -
        $191.66) than sire A’s offspring.
        This program assumes all offspring are marketed
        based upon carcass value and replacement females are
        purchased or raised as a separate enterprise. Inputs
        should be provided based on historical information from
        your operation. The TSI economic default value is based
        on a three year rolling averaged utilizing USDA data.

        It is important to remember that this is a Terminal Sire
        Index and should not be used as the sole selection tool
        for producing replacement females. Producers should
        consider the appropriate traits for the selection of sires
        to produce replacement females.

        In an ideal selection scheme producers would select
        breeding animals that excel in all traits. In reality
        though, this is not the case. Producers often fi nd
        it necessary to make compromises in selection
        to balance the strengths and weaknesses among
        selection candidates. This is driven by the fact
        that unfavorable relationships exist between traits.
        Therefore, it is diffi cult for producers to weigh
        all the options appropriately given the various
        management programs and diversity among beef
        cattle. To make this decision even more challenging
        is the fact that not all producers sell beef cattle
        based on the same marketing grid.

        A selection index is a formal method of combining
        Expected Progeny Differences (EPD) for different
        traits into one single value on which to base
        selection decisions. The AICA Terminal Sire Index
        uses estimates of the genetic relationships between
        traits and breeder historical input data on the cow
        herd a sire is to be mated along with marketing and
        carcass grid specifi cations to determine economic

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