Five years after AHDB Dairy introduced rankings for genomic young sires, and the rate of genetic improvement in Holstein herds using such sires, has almost doubled that of previous years.

According to Marco Winters, head of animal genetics at AHDB Dairy, the industry's confidence in young sires and their genomic predictions is clearly evident as more than two-thirds of all Holstein inseminations in the UK are now attributable to such sires.

“This is a remarkable rate of adoption of a relatively new technology," said Mr Winters.

“We estimate that the additional genetic gain achieved on UK farms as a result of farmers choosing to use these superior genomic young sires, is approaching nearly double the annual gain we were achieving prior to the availability of genomic indexes in 2011.”

The new rankings published this week, show the lead genomic Holstein sire, Mr Rubi-Argonaut has retained his No 1 position, breaking the £800 Profitable Lifetime Index (£PLI) barrier in the process.

The young sire, which retains his position from the April rankings, now boasts a PLI of £819, and transmits solid production, marked by a Predicted Transmitting Ability (PTA) for fat of +0.21%. This Rubicon son out of a Shotglass dam also ranks as the best feet and legs improver amongst the young genomic bulls at +2.51.

New in second place is Peak AltaDepot (Hotshot x Montross) with a similarly impressive PLI of £818. This bull is an exceptional fitness transmitter being one of the best for Somatic Cell Count at -36, Lifespan Index is +0.9 and daughter Fertility Index a massive +17.5. At -6, AltaDepot is also a top bull for the new Mastitis index (launched by AHDB in April 2017), indicating fewer daughter mastitis cases.

VH Balisto Brook (PLI £791) climbs to third place and is another remarkable bull for udder health. With the top ratings for SCC and Mastitis (-36 and -6 respectively), Brook also demonstrates high fat transmission for both weight and percentages (40.4kg, +0.24%).

A former No 1 sire, Westcoast Perseus (Penmanship x Doorman) now ranks equal fourth with a PLI of £779. He shares this position with non-mover, Progenesis Padawan (Jedi x Enforcer), a transmitter of solid protein, high lifespan, fertility and high type (+2.43 Type Merit).

One of the best milk production transmitters of the breed features in sixth in the shape of Westcoast Guarantee. This Boastful x Tango shows genomic figures of 1045kg milk, 38.9kg fat and 35.5kg protein and combines these with outstanding SCC and Mastitis Indexes, giving him a PLI of £774.

In seventh, with a PLI of £756 is VH Balisto Brixton, which will appeal to those seeking improvements in fat and protein percentages, with +0.33% and +0.21% respectively. He is also predicted to lower feed costs for maintenance, as indicated by his Maintenance Index of -15.

Prehen Lancaster is the highest UK-bred bull, weighing in with a PLI of £751 and ranking in eighth position. The PLI of this Penmanship x Shamrock is underpinned by tremendous daughter Fertility Index of +17.1 alongside a high Lifespan Index (+0.7). Hailing from Stuart Smith’s herd in Co Londonderry, Lancaster is bred from the Laurie Sheik family. His dam, Prehen Shamrock Lady VG85, tested high on genomics herself as a calf, before calving and giving 9755kg in 305 days at 4.1% fat and 3.13% protein in her first lactation.

A notable breed outlier when it comes to fat transmission, the ninth ranked ABS Achiever, is attracting interest and excitement in the breeding fraternity. With a PTA fat of +48.7kg (+0.30% fat), he rates as one of the breed’s best and has a PLI of £743.

Rounding off the top 10 is Bomaz AltaTopshot, another production specialist which transmits over 76kg fat and protein combined. This son of Cogent Supershot, which himself is now gaining worldwide recognition as a high daughter-proven production sire, has a PLI of £740.

Other UK interest in this index run includes the 11 sons of the UK-owned Cogent Supershot now in the top 100 and a new UK-bred sire in the top 25 in the shape of ABS Exodus (Battlecry x Robust), with a PLI of £706.