Page 8 - Glenside 2020
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differences in fat distribution on a standard 300 kg carcase.  Sires with low, or negative, fat EBVs
      are expected to produce leaner progeny at any particular carcase weight than will sires with
      higher EBVs.
      Retail Beef Yield EBV (%) indicates genetic differences between animals for retail yield
      percentage in a standard 300 kg carcase.  Sires with larger EBVs are expected to produce progeny
      with higher yielding carcases.
      Intramuscular Fat EBV (%) is an estimate of the genetic difference in the percentage of
      intramuscular fat (marbling) at the 12/13th rib site in a 300 kg carcase.  Depending on market
      targets, larger more positive values are generally more favourable.
      Docility EBV (%) is an estimate of the genetic differences between animals in temperament.
      Docility EBVs are expressed as differences in the percentage of progeny that will be scored with
      acceptable temperament (ie. either “docile” or “restless”).

                                 Selection Indexes
      New Zealand Simmental selection indexes are calculated for two market specifications, namely,
      Maternal (Self Replacing) and Terminal.  These Indexes relate to typical commercial herds in
      temperate New Zealand targeting these specifications.
      Indexes are reported as an EBV, in units of relative earning capacity ($’s) for a given market.
      They reflect both the short-term profit generated by a sire through the sale of his progeny, and
      the longer-term profit generated by his daughters in a sustainable cow herd, if a proportion of
      heifers are retained for breeding.
      The Indexes are derived using BreedObject technology.  More information on this technology is
      available from the BreedObject web site.
      Maternal (Self Replacing) Index ($) – Estimates the genetic differences between animals in net
      profitability per cow joined for an example self replacing commercial herd (run in a temperate
      environment) producing steers.  This Index assumes that the joinings are to British breed cows
      where there is only a modest concern about calving difficulty.  The steer progeny are pasture
      grown and finished and marketed to produce a 300 kg carcase at 16 months.  Daughters are
      retained for breeding.  More information is available on the EBV weightings and profit drivers
      for the Maternal (Self Replacing) Index.
      Terminal Index ($) – Estimates the genetic differences between animals in net profitability
      per cow joined for an example commercial crossbred herd (run in a temperate environment)
      targeting grass-finished production.  This Index assumes that the joinings are to British breed
      cows where there is only a modest concern about calving difficulty.  Both heifer and steer
      progeny are pasture grown and finished and are then slaughtered to produce a 300 kg carcase at
      15 months.  All progeny are slaughtered.  More information is available on the EBV weightings
      and profit drivers for the Terminal Index.
      Note that $Index Values for individual animals are sensitive to the assumptions used in the
      BreedObject analysis to calculate the relevant selection index.



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