April 2021 Bull rundown

The April proof release saw DataGene release three key lists of bulls;

• Australian Proven – animals meet all criteria for listing in the Good Bulls Guide
• Balanced - includes bulls with milking daughters in Australia (A) or overseas (I-Interbull)
• Genomic

Australian Proven Bulls

There has been considerable change to the list of bulls based on complete ABVs, with a significant lift in the average BPI for the top 10. In the December run the average BPI was 361 while this month the average BPI of the top 10 is 413, an increase of 52 BPI points.

There are also a number of additions to the list who now have a complete ABV unlike in December where their proof was based on overseas data or they had insufficient data to meet publishable criteria.

The impact of this can be seen with the addition of the following bulls to this month’s top 10.

*Silver and Boastful rank equal 10^th on list.

The remaining bulls featured in the top 10 list who have maintained their representation within the elite of the breed are Contender and Harper at number 2 and 9 respectively.

Seven bulls (listed below) from December’s top 10 dropped out of the April list, despite the fact that for a number of them their proof actually improved, highlighting the tremendous BPI increase of the group overall.

Balanced Bulls

The top 10 Balanced bulls are all internationals with proofs based on overseas information. In many cases information will be sourced from many countries and include large numbers of new daughters depending on the initial popularity of the bull.

The exception is Bandares who has milking daughters in Australia included in his proof in conjunction with a very large cohort of overseas daughters.

As we review these lists it does highlight the global reach of the Holstein breed and the contribution to Australia both from domestic and international sources.

Overall the top 10 are relatively stable with 9 of the 10 bulls included in previous lists , though there are a number of changes within the rankings.

There is also one new addition at number 8, Latrobe (7HO14174) 475 BPI, an increase of +22 BPI from December, graduating from that month’s Genomic list to the Balanced April list.

Genomic

As with the Australian Proven list, April’s Genomic list sees a significant increase in the average for the top 10 bulls, lifting 30 points compared to December.

In conjunction with the lift in genetic merit, three existing bulls return to the top 10 and three make their debut, with the remaining bulls being relatively stable.

HWI Bulls

For bulls to be listed in the Good Bulls Guide there are minimum BPI standards applied thus bulls included in the HWI list must also meet minimum BPI levels, for April 2021 this is 257 BPI. Additionally to be included in this list bulls must have milking daughters in Australia or overseas. Bulls with only a genomic proof are not included.

With respect to health traits, genomic sires can play a significant role in speeding up improvement through targeted breeding programs, with breeders also reviewing the Genomic list to identify Health Weighted Index breed leaders.

With the increased emphasis on Fertility, Mastitis Resistance and Survival the HWI listing identifies bulls who excel for these Health traits. This list also identifies unique bulls for HWI,  though including bulls who also rank at the top of the breed for BPI.

Type

As a starting point breeders can  use the Overall Type listing as an alternative to the TWI.  This list allows breeders to identify high type sires that meet the minimum criteria for the Good Bulls Guide.

As breeders review the Type list it is also important to look beyond just Overall Type to identify the traits that are a priority for their specific breeding program.

# Denotes an ABV(i) using data from foreign daughters