The latest December proof sees much stability once again, with front-runners retaining their positions in the proven and genomic listings.

The Catlane herd continues to dominate in the British Friesian rankings while the Danish Jersey breed takes the top nine places in the Spring Calving Index. 

See also: Top 10 bulls from the new August bull proof run

Proven bulls (download pdf)

Genomic bulls (download pdf)

Spring calving index (download pdf)

Other breeds (download pdf)

Proven bull list

The number one position in the new profitable lifetime index (£PLI) rankings for daughter-proven Holstein bulls is held by long-term leader Gen-I-Beq Lavaman.

This bull has almost 100 more UK daughters contributing to his figures, since they were published by AHDB Dairy last August, now clocking up more than 1,000 milking in the UK.

He earns a PLI of £690, reflecting his balanced breeding profile, with a very high predicted transmitting ability (PTA) for protein percent (+0.18%) and low daughter maintenance costs (-9).

In second position is a bull which makes his debut in the proven bull rankings: Mocon. Bred in Germany to a daughter of Snowman, his sire is Morgan, giving him both Bookem and Shottle in his pedigree.

With a PLI of £679, Mocon has a PTA which combines high weight of milk (839kg) and protein (28.5kg), alongside low cell counts (-23) and favourable daughter maintenance (-19), reflecting his daughters’ smaller than average stature.

Teemar Shamrock Alphabet edges up to third place with outstanding fitness attributes including daughter fertility (Fertility Index 21.1) and good calving ease (both direct and maternal). Low maintenance costs (-23) and a high lifespan index of +0.7 help to earn him a PLI of £668.

Cell count and fertility improver, S-S-I Shamrock Mystic holds on to fourth position (PLI £640), closely followed by VH Cole Clark, another fitness specialist with 21.2 FI, +0.8 Lifespan and a PLI of £634.

Genomic young sires

Mr Rubi-Agronaut

Mr Rubi-Agronaut

One of the top milk quality improvers of the Holstein breed, Mr Rubi-Agronaut, leads the way among genomic, young sires in the new AHDB Dairy indexes, with a December 2017 profitable lifetime index (PLI) of £812.

Retaining the position he has held throughout the year, Agronaut transmits fat and protein percentages at +0.22% and +0.09% respectively, and also has the highest type merit of the top 20 sires at +3.12. This type score reflects the new emphasis on bulls with smaller stature in Holstein UK’s newly revised type merit formula.

Climbing into second place is Claynook Casper (Hang-Time x Bombero). Like all of the top PLI sires, Casper scores strongly for both daughter fertility (fertility index +13.4) and daughter lifespan (LS +0.7 lactations).

VH Balisto Brook holds on to third spot, transmitting a massive weight of fat at +40.5kg and excellent udder health, with -36 for somatic cell count and -6 for mastitis.

Fourth ranking is Peak AltaDepot, another strong udder health bull, who also has excellent daughter fertility (+17.6) and the highest lifespan index in the breed at +0.9. This indicates his daughters last nearly a full lactation longer, on average, than those of a bull with a zero score for LS – a benefit which will accumulate down the generations.

Former number one sire, Westcoast Perseus holds his position in the top five with a PLI of £788 and high protein percentage (+0.11%), and stands ahead of the first brand new bull in the top 10. This new entry, Progenesis Doctor, rates very favourably for reducing maintenance feed cost for his daughters (-6) and has a high milk predicted transmitting ability (PTA) at 811kg.

Spring calving index

The Jersey breed continues to dominate the ranking for spring calving index (£SCI). Designed to identify those bulls whose daughters are suited to spring block calving systems which place a heavy reliance on summer grazing, it is the bulls which excel for milk quality, daughter fertility and have low maintenance costs which stand out from the crowd.

Expressed on an across-breed basis and therefore using a different scale from those used for each individual breed, an impressive nine of the top 10 bulls are Danish Jerseys. It is Denmark’s long-term emphasis on breeding efficient and healthy cows which is reaping rewards for UK grazing systems.

The sole outsider is the breed-leading British Friesian bull, Catlane Caleb, who weighs in at number 10, with a particularly impressive daughter Fertility Index.

Other breeds

The domination of the British Friesian bull rankings by the Catlane herd continues unabated, as the removal from the market of long-term leader Catlane Chad makes way for his herd-mates. Bred in the heart of England close to Market Bosworth, Leicestershire, it is Catlane Caleb who rises to the top of the profitable lifetime index (£PLI) ranking published today (5 December, 2017) by AHDB Dairy.

Moving up from second position, Caleb is a low volume, high milk quality bull who transmits excellent fat and protein percentages (+0.33% fat and +0.15% protein). He also offers calving ease (his dCE of 1.7% is the best in the top five) and improves the fertility of his daughters (fertility index 5.6).

Higher production is on offer from the number two British Friesian, Kirkby Major, who weighs in with a predicted transmitting ability (PTA) of 255kg milk, 17.9kg fat and 12.1kg protein. Representing the best milk solids transmission in the top five, Major also offers good udder health and positive type merit (TM). His PLI is £370.

Remaining at number three is the high type merit Kirkby Jupiter with a PLI of £362 and TM of 2.44.

In fourth position is the only new entrant to the top five, Catlane Cromwell. With a PLI of £344, Cromwell is the best improver of udder health and daughter fertility at the top of the ranking.

Unchanged in fifth position is Skyhigh Patrol with a PLI of £323. His PTA shows a good cross-section of milk solids, fitness and Type Merit (TM 1.69).

Jersey

The Jersey breed sees little re-ranking since the August proof run, with VJ Hilario retaining his number one position with a PLI of £572. Offering high production (PTA milk of 318kg and protein of 15.5kg are the best in the top five), he also transmits good udder health (-17 SCC index) and outstanding daughter fertility (fertility index 15).

New in joint second place is Golden GDK Vivaldi with a PLI of £543. Offering remarkably high weights of fat and protein (31.9kg and 15.3kg respectively), he will also improve milk quality with +0.44% fat and +0.18% protein. Adding good feet, leg and udder traits into the mix, he scores a type merit of 1.1.

Moving up from third to share second place is the exceptional fitness bull, Danish VJ Tudvad, with a PLI of £543. His udder health transmission is the best in the top five (-27 SCC, -4 Mast) while he is also good for daughter fertility and a solid improver of percent fat (+0.38%).

Fourth and fifth placed Jerseys are both bulls from the top five in the previous proof run in the shape of Sunset Canyon Dazzler (PLI £538) and VJ Link (PLI £522). Both bulls offer a combination of production, fitness and fertility while Dazzler has the best leg, feet and udder traits and the highest overall type merit (TM 1.9) in the top five.

Ayrshire

The Ayrshire top five is dominated by red bulls from the Nordic countries which represents little change since the previous proof run. With all transmitting the good daughter health and fertility for which this region of the world is renowned, their scores for mammary conformation do not always reach the level for which the Ayrshire breed has built its reputation.

VR Gunnarstorp Backen Gobel continues to lead the way with a PLI of £564. Offering solid production and exceptional daughter fertility, he holds his lead over Pell Pers, who remains ranked second (PLI £491).

The high type Gunnarstorp remains in third position (PLI £451, TM 2.1) while fourth-ranking VR Oýòja Storegaýôrd Hasl Hat (PLI £447) transmits the highest weight of milk, fat and protein in the top five.

Rounding off the red-and-white top five is VR Dansjo Haslev Hammer with a PLI of £439.