TECHTALK - TBTS

Enhancements to Brahman GROUP BREEDPLAN

BY PAUL WILLIAMS TBTS TECHNICAL OFFICER

TECHTALK NOVEMBER 2014



Two significant enhancements will be applied to the BREEDPLAN software used to calculate EBVs for Brahman animals. They will be applied first in the November 2014 Brahman GROUP BREEDPLAN analysis, then in all subsequent analyses.

The enhancements include:

  • Incorporation of Direct Genomic Values (DGV) into BREEDPLAN – A major focus from the Beef CRC was to use phenotypic and SNP genotypes to develop prediction equations for economically important traits. These equations were subsequently validated by generating direct genomic values (DGVs). Two DGVs are now available for inclusion in the Brahman BREEDPLAN analysis: one for female reproduction and the other for post weaning weight. It is important to note that only 2068 animals currently have DGVs calculated and these animals only will benefit from having their genomic information included in published EBVs.

    • Female reproduction DGVs will now be blended into the Days-to-Calving (DTC) EBVs as part of the routine monthly BREEDPLAN analysis. Results to date show that overall EBV accuracy for DTC increased by 10%, ranging from 0 to 33%. The largest changes in accuracy are associated with animals that have a low pre-blending accuracy. Importantly there is no flow-on effect of these DGVs to other correlated traits or to close relatives.

    • Post weaning DGVs will now be blended into the 200 day weight EBVS as part of the routine monthly BREEDPLAN analysis. Importantly there is no flow on effect of these DGVs to other correlated traits or to close relatives. The overall impact on accuracy will be small, although those animals with the lowest pre- blending accuracy will benefit the most

  • Revised handling of records in the DTC analysis –

    • This is required due to more complicated joinings data resulting in extreme DTC records and DTC EBVs.

It is important to note that the revised handling of DTC records has a more widespread impact on DTC EBVs than does the blending of female reproduction DGVs, since the latter only affects those 2068 animals with DGVs available for blending

Please Note: The above enhancements will not result in significant changes in EBVs and Selection Indexes overall. For some animals, however, significant changes and re-ranking may be seen.

If you have any questions regarding the enhancements to Brahman GROUP BREEDPLAN or changes in EBVs resulting from the enhancements please contact Paul Williams Brahman TBTS Technical Officer (P: 07 4927 6066, E: paul@tbts.une.edu.au) or Brahman BREEDPLAN (P: 02 6773 3555, E: brahman@breedplan.une.edu.au)