STABILITY amongst daugh-ter-proven sires sees Bo-maz AltaTopshot retain his
number one position in the Profitable Lifetime Index (£PLI) ranking, published last week by AHDB Dairy.
With a PLI of £708, Topshot reaffirms his transmission of
high weights of milk and protein (Predicted Transmitting Abilities (PTAs) of 985kg and 33.4kg respectively) alongside excellent Lameness Advantage (+3) and good udder health (SCC -21, Mastitis -3). (Figures are expressed on the new genetic base – see panel)
Newly graduating into second place from somewhat further down on the genomic list is Westcoast Guarantee (Boastful), whose PLI of £694 is both a general indication of the genetic credentials of the newest gen-eration of daughter-proven bulls and a specific reflection of this bull’s transmission of superb udder health (SCC -22, Mast -4) and fertility (Fertility Index +13.4).
Beneath Guarantee comes lead-ing improver of daughter lifespan (LS +176 days) View-Home Littlerock, whose daughters also boast low costs of maintenance (-19), and Seagull-Bay SR Star-dust, both bulls changing little since last time with PLIs of £677 and £674 respectively.
Hoanster Zanzibar moves up
impressively to fifth from 16th
place, with 163 more UK daughters now contributing to his figures and earning him a 99 per cent reliable production PTA and a PLI of £673. He affirms his transmission of excellent calf survival (CS +3.2), udder health (SCC -19, Mast -3) and fertility (FI +15.2).
At £650, super-high production bull AOT Silver Helix is little changed in sixth position, while seventh ranking Seagull-Bay Jo Dancer (PLI £641) moves up from 14th place. Both bulls offer high milk quality.
Both Pine-Tree Verona (PLI £639) and Cookiecutter Harper (PLI £637) move from just outside the top 20 into eighth and ninth position and are followed by three bulls which tie for 10th position, with PLIs of £617.
While none of the three has UK daughters milking (their figures being based on foreign daughters and a genomic contribution), Welcome Silver Griff makes improvements in daughter fert-ility (FI +9.6), ABS Achiever continues to excel for percentage fat (+0.26 per cent) and Progenesis Unicorn is a newcomer, rising spectacularly from the genomic ranking. The lowest milk volume bull in the top 10, Unicorn transmits improvements to most health traits including SCC (-20), lifespan (+131 days), daughter fertility (+14), TB resistance (+2.3) and calf survival, which at +3.7 is the highest in the top 10.
Commenting on the daughter-proven ranking, Marco Winters, head of genetics for AHDB Dairy, says: “Some producers have turned to the exclusive use of young genomic sires but for those who prefer the higher reliability of bulls which have milking daughters, this list gives them plenty of opportunity to improve their herds.
“In particular, there are many proven sires in both the top 10 and further down this £PLI list which offer the chance of making substantial gains in daughter health and fertility.
“Since this is advocated on
so many levels – from an economic, animal welfare and a sustainability perspective – I would strongly urge producers to shortlist their bulls on £PLI and then look at the components of health as well as production in detail.”