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Sub-indexes are sometimes reported. These refer to the economic value for traits of a particular
       type –e.g. Lamb Growth vs. Wool vs. Reproduction vs. Meat Yield (carcass quality).
       All SIL indexes are expressed as cents per ewe lambing

       INTERPRETATION
       eBVs and selection indexes are a function of the population in which they are calculated. In
       all cases they are comparable within a single flock.

       For every analysis SIL sets  1995  as the benchmark year and  the average genetic merit of
       lambs born in 1995 is set to zero. Therefore, eBVs are measures of genetic merit for a ram
       compared to the 1995 average for that evaluation. If two flocks had different average genetic
       merit in 1995 the eBVs would have to be adjusted for the difference to make them comparable

       When selecting a ram that is high genetic merit it is important to first select the flock the ram
       was bred in. The ram should rank highly within that flock for the key traits you are interested in.
       Index values provide the best guide to overall genetic merit across traits.

       In summary, whichever flock you decide to buy a ram from, be sure to select one that is highly
       ranked by  SIL.  This  will  guarantee improved  genetic merit  in  your flock compared to using
       rams  selected without an accurate assessment of genetic merit.

       EXPLANATIONS FOR COMMONLY USED SIL DATA
       Abbreviations Definition
       eBV           eBVs (estimated breeding values) are expressed in the units the trait is
                     measured in, and are an estimate of the value of the ram’s genetic merit
                     for the trait
       eBV Accuracy  Indicates the amount of information used in the prediction of the eBV. Traits
                     that are more heritable and more related to other traits they are predicted
                     from have higher accuracy.
       WWT eBV       Weaning weight – “lamb growth”
       LW8 eBV       Body weight at 8 months of age – rates animals for post-weaning growth
       FATY eBV      (Whole carcass) Fat yield – kg per kg of carcass

       EMA eBV       Eye muscle area
       EMAc eBV      Eye muscle area corrected for carcass weight – a measure of muscularity
       FAT eBV       Weight of fat in carcass
       FD eBV        Fat depth ‘C’
       NLB eBV       Number of lambs born
       FW12 eBV      Fleece weight at 12 months of age
       NZTW index    New Zealand Terminal Worth is expressed in cents and is an estimate of
       (previously TSO)  genetic value for growth (TSG), meat yield (TSM) and survival (TSS).


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