Stability brings reassurance to seasonal-calving herds

With spring calvers now being bred, producers using grazing based systems will find a reassuring consistency amongst bulls ranked on Spring Calving Index (£SCI) in the April run, published today (4 April) by AHDB.

Spring Calving Index (£SCI)

Progenesis Wimbledon remains in number one position, his lower milk volume and high components combining with a very high daughter Fertility Index and shorter than average gestation lengths to contribute to his SCI of £588.

This Holstein bull’s genetic performance on this across-breed ranking, stands just ahead of second placed Denovo Invictus (SCI £552). With 427 UK milking daughters contributing to his high-quality milk index, Invictus also breeds smaller sized daughters which will improve maintenance feed costs.

New Zealand-bred Diggs Hardcopy holds on to third position with excellent fat and protein percentages, and high fertility all contributing to his SCI of £550.

A new entrant in fourth position is the leading Holstein £PLI sire, Genosource Captain (SCI £546), who will transmit more production than the typical bull at the top of the £SCI list.

The Jersey bull, VJ Groenbjerg Lobo Lobster moves up into fifth (SCI £537) transmitting the high milk components and smaller body size typical of the Jersey breed, combined with high daughter lifespan.

VJ Hoeholt Jern James – another Jersey with high milk quality traits – moves up from 20th position to now rank sixth (SCI £535), while the next three places are held by sires who previously ranked in the £SCI top 10. First is the Holstein bred Pine-Tree CW Legacy, with excellent udder health characteristics; and next are the Danish Jerseys, VJ Zummit (SCI £525) and VJ Ravninggaard Huus Hamlet (SCI £520). Zummit transmits slightly higher yields with more favourable maintenance, whereas Hamlet displays higher fertility and lifespan traits.

Rounding off the top 10 is the Holstein, Denovo 7921 Atrium (SCI £519) with high milk solids and good udder health.

Autumn Calving Index (£ACI)

Producers calving in an autumn block may also look to the versatile sire, Genosource Captain, who takes the lead in the £ACI ranking with an ACI of £708, having graduated from the genomic list.

Progenesis Wimbledon moves up into second (ACI £677), and last time’s number one, Pine-Tree CW Legacy ranks third, (ACI £661).

Denovo Invictus (ACI £645) makes significant gains on adding UK daughters, moving up to fourth position ahead of Aardema Pistolero (ACI £641).

Three familiar bulls – Westcoast Guarantee, FB 326856 Medley Baynes and Bomaz Monument-P – all weigh in with £ACIs of £631 in equal sixth position.

Cell count improver, Westcoast River, ranks ninth, ahead of Bomaz Complex, bringing up the rear in 10th position.

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.