DataGene advises that updated BPI and HWI models were effective from the routine ABV release on 4 November 2020, which is available to customers only. December will be the first public ABV release using the updated models. The updates have had has had an impact on the animals’ index values and rank positions. In particular, animals that are strong for fertility are likely to have higher index values and rise in rank position.
These updates are the results of review and consultation with industry.
Balanced Performance Index (BPI)
- updated with current economic values for fat, protein, feed and labour.
- greater emphasis on health traits and less emphasis on production traits, compared with 2019 BPI.
- Jersey BPI excludes Feed Saved, reflecting differences between breed objectives and differences in the evaluation of the Feed Saved ABV.
Health Weighted Index (HWI)
- updated with current values for fat, protein, feed and labour.
- double weighting on Daughter Fertility.
- modelled on a strictly seasonal calving system.
Type Weighted Index (TWI)
- replaced by Good Bulls Guide tables that rank bulls by Overall Type and Mammary System.
The base (used to compare animals)
- unchanged but with a breed purity filter added so it is a truer reflection of the breed.