August 2020 bull proofs: The latest movers and shakers

Seven new Holsteins enter the top 10 ranking for young genomic sires published today (11 August) by AHDB Dairy.

The previous front-runner, Genosource Captain, clings on to the number one position.

With a Profitable Lifetime Index (£PLI) of £861, Captain transmits high fat (50kg, +0.14%) and excellent feed savings seen through a negative Maintenance Index (-15). His daughters’ fertility is also predicted to be impressive (Fertility Index +10.7), while he is also the best bull for Lameness Advantage in the available young bull list (+4.5).

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Holstein cow

The Genosource Captain dam Genosource Sabre 3522 © Cogent

Hot on his heels is a new entry, Peak AltaPlinko (PLI £857), a son of Progenesis Marius from a Bomaz AltaTopshot dam. Plinko is the highest transmitter of combined fat and protein (47.6kg fat and +40.3kg protein) and also transmits an impressive 1,038kg milk.

His close relative (also a Marius x AltaTopshot, but from a different cow family) is Peak AltaZazzle, who ranks third (PLI £817). This new entry is the highest fat transmitter (53.2kg, +0.21%) and also offers solid daughter lifespan figures (+125 days).

Denovo 15848 Kenmore ranks fourth (PLI £811), transmitting good improvements to somatic cell count (SCC -24) and very good calf survival (CS +3.8). He too is newly available since the previous (April) genetic evaluations.

In fifth place is a DG Charley son, Denovo 14566 Crosby (PLI £806), with excellent udder health figures (-27 SCC, -4 Mastitis) as well as outstanding Lameness Advantage (+4.3).

The next four bulls, in sixth to ninth place, are all new entries (see table below).

Download the PDF: Young holstein sires

Proven sires

The new number one daughter-proven Holstein, with a Profitable Lifetime Index (£PLI) of £737, is the Boastful son Westcoast Guarantee.

Improving as new daughters are added to his Predicted Transmitting Abilities (PTAs), Guarantee edges up from second position in the previous index run, thanks largely to the superb cross-section of health, fertility and efficiency traits he passes on to his daughters.

These include -25 SCC Index, -4 Mastitis Index, favourable maintenance feed costs (-7), and excellent Fertility Index (+13.8). All of this contributes to his impressive Lifespan Index (+119 day), meaning his daughters will, on average, live 119 days longer than the UK-average cow.

The only new entrant in the top 10 proven bull rankings is a Guarantee stablemate, Westcoast Yamaska. This Afterburner son earns a PLI of £696, confirming his young sire genomic credentials as a components improver (+0.23% fat, +0.16% protein). He also has the best TB Advantage in the top 20 proven sires, at +4.9, and a Type Merit of +1.97.

Third placed Welcome Silver Griff moves up from tenth position in April, transmitting outstanding weights of fat and protein (49.4kg fat, 31.9kg protein) and earning a PLI of £688.

View-Home Littlerock now ranks fourth (PLI £672), with the best Maintenance Index in the top 20 (-20), superb lifespan (an extra 146 days) and good calving ease (dCE +0.9).

Holding on to fifth place is Hoanster Zanzibar, the best daughter fertility transmitter in the top 20 at FI +15.6, and now with 463 UK daughters contributing to his PTAs.

Download the PDF: Daughter-proven sires

Autumn Calving Index

A small reshuffle at the top sees Westcoast Guarantee take the lead, his ACI of £657 reflecting marginally better udder health than the number two bull, Hoanster Zanzibar (ACI £615), which he replaces at number one. However, both these bulls excel for udder health and fertility, as demonstrated by this across-breed ranking, whose top 20 this month is monopolised by the Holstein breed.   

Third ranking Progenesis Unicorn moves up, ahead of two UK-bred sires, which take joint fourth place. Both Bellemont Perks and Glamour Boghill Casper have ACIs of £595, with both showing strong credentials for percentage fat.

Spring Calving Index

On the Spring Calving Index (£SCI) list, there is more of a mixture of breeds, with the top spot remaining in the hands of Jersey sire Danish VJ Tester (SCI £467). Tester’s strong milk components earn him the lead in this slightly more components-focused index, over the higher-yielding Holstein Westcoast Guarantee, in second place.

Progenis Unicorn ranks third on £SCI, while UK-bred Glamour Bogill Casper moves up to fourth place. Hoanster Zanzibar now ranks fifth, and the high-components Holstein Mr Rubi-Agronaut joins the top tier with an SCI of £421.

Download the PDF: Block calving indexes

Other breeds

The Jersey sire River Valley Cece Chrome strengthens his claim to the number one position. Having earned this place in the April proof run, he now breaks the £600 barrier for Profitable Lifetime Index, at PLI £605. Transmitting extreme production to his daughters, with Predicted Transmitting Abilities (PTAs) of 857kg milk, 37.5kg fat and 28.6kg protein, his Type Merit of +1.9 also makes him the leading transmitter of overall conformation.

Remaining in second position is Danish VJ Raastrup Hihl Gislev, transmitting high daughter lifespan (adding 101 days to the average herd life) and favourable udder health (-21 SCC, -2 Mastitis). His PLI is £509.

Also retaining his position is Danish VJ Blanke Jason Janko, ranked third and offering one of the highest milk component indexes in the top 10 at +0.34% fat and +0.18% protein. His PLI is £414.

Two sires level-pegging at £402 PLI round off the top five, in the shape of Danish VJ Zummit and Danish VJ Tudvad. Tudvad transmits the highest percentage fat in the top five at +0.42% and excels in udder health (-31 SCC, -4 Mastitis), Lifespan (+110) and daughter Fertility Index (+10.9).


Gaining enough milking daughters to make the official ranking, Inch Persistent becomes the new leader on the British Friesian list, with a PLI of £413. Now with 17 daughters in six herds, he is predicted to transmit high fat (19.4kg, +0.23%) and good lifespan (+104 days).

He is joined by his full brother, Inch Patrick, in second position (both are Lakemead Pinnacle sons out of Inch Blackisle Daphne 2) who shows a very similar breeding profile and has a PLI of £360.

Kirkby Malvern climbs into third place with strong production gains taking him to 418kg milk, 31.8kg fat plus protein and a PLI of £350.

The gains of the new bulls push the 99% reliable Catlane Caleb to fourth position (PLI £339), although he continues to be the breed leader for fat and protein percent, at +0.27% and +0.15% respectively. He also remains the dominant force for daughter fertility, at FI +7.9.

Rounding off the top five is Catlane Cromwell, whose good Calf Survival (CS +6.5) and cow lifespan (LI +128 days) contribute to a PLI of £326.


The application of breed purity criteria to the Ayrshire list sees the removal of the former leading bull, allowing VR Gunnarstorp Backen Gobel to move up one place to take the lead. Gobel earns a PLI of £501 and an excellent daughter Lifespan Index (+116 days).

Moving up to second position is VR Alatalon Flame Feton, whose good protein percent (+0.11%) and breed leading fertility (FI +17.1) help earn him a PLI of £454. He also has a high Type Merit at +2.1.

Remaining in third spot is Pell Pers (PLI £429), now with 1,107 UK milking daughters and displaying good udder health (-17 SCC, -2 Mastitis) and desirable maintenance (-38).

VR Kuusian Valpas Vimpula (PLI £424) moves to fourth, outranking his competition on production figures with 688kg milk and a whopping 50.6kg fat plus protein.

VR Stenkulla Vimpula Vilano holds his position in the top five with good protein percent (+0.13%) and high daughter fertility (FI +13.9). His PLI is £422.

Download the PDF: Other breeds