Young sires without compromise as Genosource Jumpstart new number one

The AHDB young sire evaluations are awaited with keen interest by progressive Holstein breeders and this month they are rewarded with a new number one bull.

Ranked on Profitable Lifetime Index (£PLI), Genosource Jumpstart P takes the top position, transmitting 56.8 kg (+0.28%) fat and 35.9 kg (+0.12%) protein, alongside a favourable Mastitis Index of -2.

This earns him a PLI of £919. Jumpstart’s sire is Genosource King P, a bull which also features strongly in the rankings in 12th position and combines outstanding production with excellent health credentials and, like his son, has the added advantage of being polled.

Climbing into second place on £917 PLI is Genosource Judo, a son of OCD Fugleman Radical. Judo is the highest milk and protein bull in the top 20, transmitting 1,288 kg milk and 47.2 kg protein. He also shares the highest EnviroCow score among the leading bulls at 4.9.

Ranking third, with a PLI of £907, is Peak AltaSpinwin, a newly available son of AltaMakeover. Spinwin combines strong production with favourable management characteristics, including Maintenance of -24 and a daughter Fertility Index of 6.8.

At 4.9, he also shares the highest EnviroCow score in the top 20. AltaMakeover’s influence is evident throughout the rankings, with three sons featured among the top 20 bulls.

Moving into fourth place is OCD Thorson Ripcord whose PLI of £905 reflects his excellent efficiency and fitness transmission. This bull has one of the most favourable Maintenance figures in the rankings at -32 together with an impressive Fertility Index of 10.3.

These August rankings highlight the growing influence of the Thorson bloodline, with descendants featuring prominently throughout this new top 20.

New entrant, Genosource Hemi, makes an immediate impact in fifth place, with a PLI of £891. Hemi combines exceptional fitness traits, including 153 days of extra lifespan and a daughter Fertility Index of 11.5, contributing to a strong index for HealthyCow of £249.

Completing the top six is Denovo Canterbury at £887 PLI. This UK-born son of Absolute transmits outstanding milk solids at 60.3 kg (+0.29%) fat, while also boasting a strong EnviroCow of 4.8.

Jointly ranked seventh are Peak AltaRotation and Genosource Lingo, both on £880 PLI. Lingo stands out as one of the strongest milk quality transmitters in the ranking with +0.38% fat and +0.17% protein.

OCD Radical Josh Allen retains ninth position on £879 PLI, while rounding off the top 10 is Peak AltaFanbase. With a PLI of £871, he is also the highest-ranked bull for Feed Advantage at 298.

Other notable bulls within the top 20 include new entrant, SFH Scudetto Red (PLI £865), also the highest lifespan transmitter in the group at +192 days, and Peak AltaSovereignty.

This bull is the leading fat transmitter at +63.5 kg and +0.35% and earns a PLI £857.

Health-conscious breeders may also be attracted to Denovo Caterpillar, a bull combining excellent udder health traits at -29 SCC and -3 Mastitis, while ABS 18 Galactic offers a strong combination of fat production and daughter fertility. Both have a PLI of £853.

Marco Winters, Head of Animal Genetics, AHDB said:

"What stands out in this evaluation is that the top bulls no longer excel in just one area. Today’s leading sires combine strong milk solids with improvements in health, fertility, efficiency and environmental performance, giving breeders greater confidence that genetic gain can be achieved without compromise.

"The presence of high-ranking red and polled sires in the top 20 also demonstrates the continued broadening of breeding options available to UK dairy farmers."