The October Hereford BREEDPLAN analysis has now been completed and published. There have been a number of enhancements to this analysis, with two enhancements in particular likely to have caused some changes to EBVs as well as the current breed average and the percentile bands. The first of these is a change to the weighting that is used to combine relationship information that comes from pedigree records and from genomic tests. The second is the implementation of a new Single-Step Calving Ease analysis.
In addition to these changes there have also been two new indexes published for the first time, Sustainability Production Index and MSA Production Index.
To help keep members informed about what has caused changes to the EBVs and Indexes for their animals we have compiled a list of Frequently Asked Questions shown below.
For more detailed information about these changes please see the Hereford BREEDPLAN analysis updates article on the Herefords Australia website.
FAQs
Why have the Calving Ease EBVs for animals in my herd changed?
There have been changes to the model that is used to calculate Calving Ease EBVs. These changes include moving to a Single-Step Calving Ease analysis that includes genomic information for the first time and also changes to how contemporary groups are formed.
Hereford BREEDPLAN changed to a Single-Step analysis in 2017, however at the time the method to analyse Calving Ease the same way had not been developed. The current update brings Calving Ease into line with the rest of the analysis. These changes mean that more animals are now included in the Calving Ease analysis and there is significantly more data being used. This gives us access to much higher accuracy Calving Ease EBVs and means that can make faster rates of genetic improvement for these traits.
Have animals changed in their ranking for Calving Ease?
Yes. These updates mean that we now see a greater range in Calving Ease EBVs within the Hereford breed and we also see updated rankings for animals within the breed. This has happened because of the high number of animals with Calving Ease data now in the analysis and a better understanding of the relationship between animals due to the use of genomics.
It is important to compare the updated EBVs for your animals to the updated percentile bands for Calving Ease to understand where your animals rank within the breed.
What has caused my animals’ EBVs for other traits to move?
Separately to the updates to the Calving Ease model, there has been a change to the weighting that is used to combine relationship information that comes from pedigree records and from genomic tests used to calculate EBVs for all traits. This weighting (referred to a Lambda) has been changed from 0.50 to 0.95. This means that the proportion of genes that animals share is more strongly influence by genotype. Again, this means that we can calculate higher accuracy EBVs.
It does not change the emphasis on phenotypes in the analysis.
As with any other routine analysis, it is also possible that new data that has been added to the database prior to the October BREEDPLAN analysis may have caused some animals’ EBVs to change.
Why can’t I find the new indexes for my animals on the Herefords Australia website?
The October Hereford BREEDPLAN analysis has also seen two new indexes being published for the first time, Sustainability Production Index and MSA Production Index. To give members the opportunity to understand how their own animals rank within the breed for the new indexes before this information is published more widely, we have taken the approach of only reporting the new indexes in your herd reports at this stage. They have not been published to the Herefords Australia website for now.
The new indexes will be published to the website as of the November BREEDPLAN analysis date. The four indexes previously reported by Hereford BREEDPLAN will be removed as of the November analysis.
