The new ranking for young Holstein sires, published recently by AHDB Dairy, features some show-stopping figures, made all the more remarkable when the five-yearly base change, which was implemented with this proof run, is considered.
The number one sire is new entry, Genosource Captain (Charl x Sabre x Ahead), whose genomic Profitable Lifetime Index (£PLI) of £882 reflects his extreme Predicted Transmitting Abilities (PTAs) for production (1016kg milk, 49.1kg fat), combined with excellent maintenance (-14) and leg health. This is demonstrated through a Lameness Advantage +3.0 and a score of +0.6 for the newly introduced Digital Dermatitis Index.
These figures are particularly impressive in the light of the base change, which knocks £142 off each bull’s £PLI since the last (Dec ’19) index run, as the average is adjusted downwards to reflect the genetic progress made over the past five years.
Captain ranks over 90 £PLI points ahead of the new entry in second place – FB Kenobi Targaryen (Kenobi x Jedi), whose PLI is £790. Targaryen is a high protein transmitter (35.9kg, +0.09%), with excellent predicted calf survival (+3.5).
A PLI of £774 is enough to move former top 10 sire, Denovo 15158 Admiral (Torque x Yoder) into third position and he becomes the highest weight of fat transmitter in the top 20 (+50.3kg, +0.24%). Admiral is also predicted to transmit good maintenance (-9) and calving ease (+1.1).
A newcomer since the December run, although made available earlier this year, Westcoast River (Guarantee x Montana) features in fourth position with a PLI of £771. River’s genetic predictions are sky-high for udder health (-29 SCC, -3 Mastitis), while daughter Fertility Index is an impressive +15.6.
Denovo 14566 Crosby now ranks fifth with a PLI of £770 and the best leg health in the top 20 (+3.4 LA, +0.7 DD).
In joint sixth position, Cal-Roy-Al Darbee (PLI £767) is the highest protein transmitter in the top 20 at a massive +41.7kg. He also offers the best Calf Survival Index (+3.8) and Type Merit (TM) at 2.27, under a revamped TM formula which places more emphasis on feet and legs and smaller stature than previously.
Equal sixth is another new entry since December, Aardema Pistolero (Guarantee x Commander), whose PLI of £767 reflects the prediction of long daughter lifespans (+161 days).
Eighth ranking Koepon Raptor (Lawson x Topshot) is another newcomer, this time offering exceptional milk quality (+0.28% fat, +0.14% protein) with outstanding daughter lifespans (+210 day) and fertility (+14.3). His PLI is £763.
Ninth position is shared at a PLI of £761 by Prismagen Grande Rio and the UK-bred Boghill Glamour, both of which edge up from just outside the top 10. Rio’s maintenance of -19 reflects his daughters’ lower maintenance costs and he also has the best digital dermatitis prediction in the top 50 at +0.8. Meanwhile, Glamour’s notable strength is his daughter fertility (+12.2).
Just outside the top 10
Four further newcomers just outside the top 10 are Blumenfeld Sedona (Skywalker x Apprentice), notable for high TM and milk quality (PLI £760); Bomaz Kettle (Kenobi x Topshot), also increasing milk quality (PLI £755); Denovo 14744 Ginetta (Guarantee x Delta), with a PLI of £746 and Mr Wings Norton (Wings x Nominee), with a PLI of £742.
With breeding companies choosing to launch large numbers of new bulls with this proof run (almost half the top 50 are new releases), UK producers have a wide selection from which to choose. However, as always, they will need to check pedigrees closely to ensure they maintain their herds’ genetic diversity.
“Having so many new bulls certainly gives breeders plenty of choice but that can sometimes feel overwhelming,” says Marco Winters, head of animal genetics for AHDB Dairy. “I would strongly recommend farmers clearly set their own breeding goals and then use one of the breed societies’ or breeding companies’ proprietary mating programs to help them select bulls which meet their needs. By specifying a limit to minimise increases in inbreeding through these programs, or by using AHDB’s own Inbreeding Checker [available free of charge through the genetics and breeding section of the AHDB website], farmers can help to maintain genetic diversity through their choice of sires.”