Bulls ranked on new £SCI show production efficiency

The April release of dairy genetic evaluations, published today by AHDB marks the first major run using the updated Spring Calving Index model, and as expected the revisions have produced a shake‑up at the top.

The new £SCI places greater emphasis on energy efficiency, fertility, health and functional traits, and introduces a penalty for high‑production daughters with elevated energy demand. As a result, the index now better reflects the needs of UK spring calving herds.

This release also reflects the updated £SCI genetic base, recalibrated to the performance of spring block calving cows. This ensures the index continues to benchmark bulls against the genetics most relevant to UK spring calving systems.

The Jersey, VJ Boman Lasky Lando moves up to take the number one position with an SCI of £448. He offers exceptional maintenance, fertility and udder health, aligning strongly with the needs of efficient, low‑input herds.

In second place, Holstein‑bred Denovo Invictus (SCI £408) rises thanks to his combination of excellent fertility, favourable SCC and an expanding UK daughter base, making him a reliable choice.

Taking third place is VJ Kjoelby Higher Highlan (SCI £398), a leader for milk quality, reflecting the new model’s weighting towards high value milk.

VJ Outrup Luxi Luxplus sits just behind in fourth (SCI £397), offering desirable longevity, strong components and all‑round balance.

The upward movement continues with VJ Ravninggaard Huus Hamlet (SCI £393) in fifth, excelling in daughter health – a trait now more strongly rewarded under the revised model.

A notable new addition in sixth is VJ Drostrupgaard Jojo Jabra (SCI £369), delivering desirable mastitis resistance and SCC performance, while VJ NR Haugaard Hays Hauga takes seventh (SCI £364), promoting excellent daughter longevity.

Breaking the Jersey run, FB 442861 Knighton P ranks eighth with an SCI of £355. Knighton offers exceptional milk, fat and protein kilos combined with desirable fertility, demonstrating that the revised £SCI continues to reward higher yielding Holsteins when they achieve production efficiency.

Rounding off the top 10 are VJ Risholm Luxi Lagoa P (SCI £352) and VJ Ulvsbjerg Giant Giga (SCI £340), both delivering strong udder health advantages, with Lagoa’s outstanding maintenance giving him a further edge.

Of particular note is the strong performance of New Zealand genetics under the revised weighting, with seven bulls appearing in the top 20. These include the highest ranking NZ sires Mill‑Ridge TS Finn S1F (SCI £314) and Glen Kaycee Sherlock JG (SCI £313).

Autumn Calving Index (ACI)

Winstar Graziano continues his dominance at the top of the Autumn Calving Index rankings at £555, driven by excellent milk components and strong SCC performance.

Moving into second, Winstar Maserati P (ACI £547) maintains his momentum with high milk solids transmission.

Third ranking Denovo Invictus (ACI £528) remains a reliable choice for fertility and maintenance, closely followed by FB 442861 Knighton P (ACI £520), who offers a similar balanced trait profile.

SDG‑PH Delux Dominance (ACI £515) ranks fifth, excelling in milk solids, while Peak AltaSolace (ACI £514) follows in sixth with notable advantages for udder health and fertility.

Taking seventh, Cogent Koepon Rocky (ACI £508) combines strong milk, fat and protein kilos with favourable maintenance.

Peak Mauney (ACI £503) remains inside the top 10 in eighth, supported by exceptional daughter fertility.

Rounding off the top 10 are Genosource Captain (ACI £502), offering strong production with good maintenance, and Peak Powerhouse (ACI £493), delivering high kilos of milk and solids.

Victoria Ashmore, animal genomics manager, AHDB, said:

"Breeding indexes are regularly fine-tuned as industry needs dictate, and we are delighted we’ve been able to revise the formula of £SCI with these evaluations to better meet the needs of spring calving producers.

"We can see the effects in the type of bull rising to the top of the £SCI ranking, which is dominated by transmitters of high quality milk whose daughters will be capable of maintaining high health and efficiency under tight block calving, grazing based systems.

"As usual, it should be noted that these seasonal calving indexes are for use across the breeds, allowing producers with crossbred herds to easily compare the performance of any dairy breed against another.

"However, it’s important to remember that £SCI and £ACI cannot be compared with one another and equally, figures used to calculate these block calving indexes cannot be compared with any figures from the breed-specific £PLI lists."

No comparison

Block-calving producers are reminded not to compare the component figures of the £SCI or £ACI with those used in the calculation of Profitable Lifetime Index as £PLI is calculated at a breed level, whereas the seasonal indexes are expressed across the breeds and, hence, use a different average.