Clean sweep of new-launch bulls widens genomic Holstein choice

A clean sweep of new-launch bulls fills the top 10 positions in the ranking for young genomic sires, published today by AHDB.

Never seen before in a dairy bull ranking, this all-new top 10 demonstrates the fast-moving nature of Holstein breeding and sees bulls which appear in their own right within the top 20 also featuring as sires of sons at the top of the same list.

The new number one bull is Denovo 20723 Columbia, whose sire, Denovo 2776 Leeds, is proving to be one such influential bull. With a huge Profitable Lifetime Index (PLI) of £938, Columbia is predicted to transmit many of the traits sought by modern dairy producers.

Among them are a high Feed Advantage (FAdv), indicating that he will help producers breed animals which use the least amount of feed for their milk production needs.

With a FAdv of 247, Columbia daughters are predicted to require 247kg less dry matter in each lactation than daughters of a bull with a score of zero and at the same level of production.

Columbia also transmits good udder health (-17 SCC, -2 Mastitis) and extreme protein yields, with a Predicted Transmitting Ability (PTA) for weight of protein of 42.9kg.

In second place, with a PLI of £934, comes the Cookiecutter Holysmokes son, T-Spruce Harmony, whose exceptional daughter Fertility Index (11.7), udder health (-19 SCC, -3 Mastitis) and high Lifespan Index (+183 days), help earn him one of the highest HealthyCow (HC) indexes of the breed (315).

This means the better health he will transmit is worth, on average, £315 for each of his daughters over their lifetimes, compared with a bull whose HC is £0.

Two more sons of Leeds feature in third and fourth place – Denovo 20771 Segment (PLI £932) ranking third with high fat (54.1kg) and a strong Lameness Advantage (2.7), and Denovo 20893 Harmony, at £931, ranking fourth. Harmony is also the breed leader for combined weight of fat and protein at 97.7kg and, with a superb Maintenance Index (-29), also has the best Feed Advantage at 299.

This, together with the transmission of high yields, health and efficiency also contributes to the best EnviroCow score of the breed (5.2). This has the scope to help producers improve the environmental efficiency of milk production through breeding – the most effective approach to making permanent, cumulative and long-term gains.

The next newcomer, ranking in fifth position, is Cogent B Advantage. This young sire has the best daughter Fertility Index in the top 20 (12.9) and the joint highest Lameness Advantage (2.9). His PLI is £904.

Also scoring 2.9 for Lameness Advantage is sixth-ranking Denovo 2068 Hierarchy, a bull with high fat PTAs (57.1kg, +0.24%) and a PLI of £902.

Winstar Reggie is the leading transmitter of maintenance (-41), meaning daughters require less feed for their own body maintenance – something that’s also reflected in a good score for Feed Advantage (287). Daughters are also predicted to inherit high milk quality (+0.25% fat, +0.08% protein) from their sire.

The leading milk transmitter, Bomaz Lambert, has a PTA for milk of 1273kg and a PLI of £891, earning him eighth position.

The final of no less than five Denovo bulls in the top 10 is Denovo Atlas, whose PLI of £883 reflects his good PTAs for milk components (+0.29% fat, +0.12% protein).

Rounding off the top 10 is S-S-I Holysmokes Simon (PLI £879), who is an excellent transmitter of low cell counts (SCC -21) and has the best Lifespan Index of the top 10 bulls at +186 days. Combining this with a Fertility Index of 11.4 helps earn him the highest HealthyCow rating in the top 10 at 319.

Just outside the top 10

Other newcomers since the last proof run (April ’24) are T-Spruce F Bite Fionn (PLI £868) who ranks 12th and is a high daughter fertility transmitter (10.9); Denovo 20108 Athletic (PLI £860) who ranks 16th and has one of the best Lifespan Indexes (+180 days); high protein transmitter, Denovo 20730 Logic in 18th place (PLI £846) and Genosource Maui (PLI £845), ranking 20th.

Marco Winters, AHDB Head of Animal Genetics, said:

“It is exciting for dairy producers to see 10 completely new bulls in the top 10 positions and drilling down into their breeding credentials reveals they offer truly modern breeding patterns.

“Many producers are focusing on the genetics of economic and environmental traits alongside health and fertility, and bulls like those at the top of this list are helping them do so.

“And like all genetic improvement, it is possible to chip away and make small gains with each generation for traits such as Feed Advantage and HealthyCow, but see truly meaningful improvements both across a whole herd and across the generations in years to come.”

De-su Frazzled 6984 is the maternal grandam of Denovo 2776 Leeds