Dead-heat at the top for genomic young sires

Published 3 April 18

There’s a dead-heat at the top of the new genomic sire rankings which – combined with four new bulls in the top 10, 10 newcomers in the top 20 and the introduction of three newly developed genetic evaluations (see panel) – makes this month’s young sire offering of particular interest to Holstein breeders.

Published today by AHDB Dairy, the Profitable Lifetime Index (£PLI) ranking sees both Mr Rubi-Agronaut and the De-Su 13050 Spectre son, ABS Outback take the joint lead, each with a PLI of £814. Agronaut retains the position he previously held, with an index which features high milk quality (Predicted Transmitting Ability (PTA) +0.24% fat and +0.10% protein) and the highest Type Merit, at +3.12, amongst the top £PLI bulls. Meanwhile, Outback stands out for low feed costs for Maintenance (-2) as well as a strong rating for the newly released Lameness Advantage at +2.3.

Paternal half-brother to Outback, also by De-Su 13050 Spectre and also new in the top 10, is ABS Crimson (£784 PLI). Crimson is a production specialist, transmitting 952kg milk with an incredible 49.7kg fat.

The familiar names of components transmitter, VH Balisto Brook (PLI £783) and health and fertility specialist, Peak AltaDepot (PLI £781) are in fourth and fifth place, while former number one sire, Westcoast Perseus, ranks sixth (PLI £766). Claynook Casper joins the fray in seventh position, with a PLI £764 and a strong Lameness Advantage of +2.3.

New in eighth place is the Jedi son, Bomaz Skywalker (£760 PLI). Skywalker is a high protein transmitter (PTA 32.7kg), who scores well for Calf Survival at +2.5.

Progenesis Doctor now ranks ninth (PLI £757), and rounding off the top 10 is another new entry, Co-op Aardema Juicy (£756 PLI). Both Doctor and Juicy have very favourable maintenance scores (-5) and Juicy combines this with high protein (32kg) and a good Calf Survival Index (+2.2).

Just missing out on the top 10 is the UK-bred Prehen Lancaster – again with favourably low maintenance costs – while 12th ranking No-Pe Zekon cannot go without mention. As the highest ranking Czech bull ever seen in the UK rankings (PLI £749 and with 994kg milk), he demonstrates how the best genetics are internationally sourced for the benefit of UK farmers.

As genetic indexes reach new highs with this latest tranche of young sires, Marco Winters, head of animal genetics for AHDB Dairy says: “To help improve farmers’ competitiveness, AHDB Dairy has created a set of six key performance indicators (KPIs) which farmers should benchmark their herds against to identify areas for improvement and one of these KPIs is the genetic merit of the herd.

“It is critical that farmers don’t underestimate the impact of using the right genetics and the easiest and fastest way to make improvement in this area is by choosing the next group of mating sires from amongst these top genetic merit bulls.”

What’s new in Holstein indexes this month?

Three new genetic evaluations – Lameness Advantage, Calf Survival and the Dairy Carcase Index – have been launched by AHDB Dairy this April, and are now published for bulls who either have progeny in the UK, or who have had their genotype submitted for assessment by AHDB Dairy.

Details and scales for the indexes are as follows:

New evaluation


The Calf Survival (CS) PTA has been developed using close to three million animal records from the British Cattle Movement Service (BCMS), which show that calves of some sires are more likely to survive their first 300 days of life than those sired by other bulls. CS has not yet been incorporated into the UK’s national breeding index, Profitable Lifetime Index (£PLI), but is planned for inclusion later this year. A stand-alone list for CS is published on the AHDB Dairy website.

CS is published on a scale of about -5 to +5. It represents survival between tagging and 300 days. Each percentage point represents a 1% improvement in survival of a bull’s progeny.

The Lameness Advantage (LA) is calculated directly from on-farm lameness incidents recorded by the milk recording organisations, NMR and CIS. This information is combined with existing data for locomotion and feet and legs, together with bone quality scores and digital dermatitis records from the National Bovine Data Centre (NBDC) type classification system. LA will be incorporated into £PLI later this year. A stand-alone list for LA is also published on the AHDB Dairy website.

LA is published on a scale of about -5 to +5. For each percentage point, 1% fewer daughters go lame.

The Dairy Carcase Index (DCI) is primarily based on average daily carcase gain and carcase conformation calculated from weight and age data from most major abattoirs in the UK. The DCI will be of particular interest to dairy farmers producing youngstock for the beef supply chain or rearing their own beef. The DCI is not included in £PLI. A stand-alone list for DCI is published on the AHDB Dairy website.

DCI is published on a scale of about -5 to +5. For each percentage point, an improvement is predicted in both carcase conformation and average daily carcase gain in a bull’s progeny.