The top two young sires ranked on genomic £PLI remain unchanged in the new DairyCo rankings (published 7 April 2015), with the two Canadian Enforcer sons, Penmanship and Boardshop, retaining the number one and two positions. Penmanship’s PLI of £724; his outstanding lifespan transmission (LS Index +0.7); good production (Predicted Transmitting Ability for milk 614kg) and high daughter Fertility Index (FI +10.4), keep him firmly in the lead.

Penmanship’s paternal half-brother, Boardshop shows a similar transmitting pattern and has a PLI of £657.

Third placed Firewall (AltaJackman x Shamrock), edges up from fifth position and, like the two bulls above him, is a son of a genomic young sire. Milk quality and low maintenance costs are features of his index, including fat transmission of +0.17%. His PLI is £648.

Fourth ranking De-Su Acrobate (Jetset x Bookem) is the highest new entry with a PLI of £639 and, like the bulls above him, transmits the high £PLI characteristics of strong production, high fitness and solid conformation.

De-Su Octavian moves up to fifth position and is the highest Numero-Uno son in the rankings, with a PLI of £633. With an SCC Index of -31, he is the best cell count improver in the top 10.

There’s little change in position for LittleRock (PLI £624), Pacific (PLI £621) and Bullseye (PLI £619) leaving seventh and 10th positions to be filled by two brand new bulls. Cookiecutter Harper (Balisto x Epic) weighs in with a PLI of £622 and transmits high fat and protein (PTA 35.2kg and 27.8kg, respectively), although he combines this with a small negative daughter Fertility Index (-0.7).

And 10th ranking Mr America Chacal (CashMoney x Robust) combines high milk solids with excellent health and type credentials.

Other new entries in the top 20 are Topcroft Pesky Trix (PLI £612), a Pesky out of Topcrop Iota Trixie x Mascol x Roxell, bred in the UK from a British cow family; De-Su 12109 Battlecry (Balisto x Numero Uno) with a PLI of £597; and Ladys-Manor l-Brn Amryn (La-Bron x Dorcy) with a PLI of £596.

“These top genomic young sires offer the best that Holstein breeding globally has on offer,” says Marco Winters, DairyCo head of genetics. “They outperform the older proven sires on every level, with high fitness, fertility and conformation, alongside solid production figures.”