With spring calving behind us and service getting under way in most spring block calving herds, the April 2020 Spring Calving Index (£SCI) ranking, published today (7 April 2020) by AHDB Dairy, is just as likely to affirm the suitability of semen purchases made as guide this season’s breeding choices. With a mix of Jerseys, Friesians and Holsteins amongst the top 10 in this across-breed ranking, producers should feel reassured that any of all of these breeds could suit their spring block calving system.
In the lead is the long-standing Danish Jersey success story, VJ Tester, whose SCI of £465 reflects his transmission of high quality milk and low maintenance costs, which he combines with good udder health and daughter fertility.
Former front-runner, the Holstein, Stantons Most Wanted is edged into second position with an SCI of £441, offering a far higher milk volume, yet still maintaining positive components with superb udder health and daughter fertility.
Hoanster Zanzibar rises from 10th to third position, emulating the rise he experienced in the Holstein £PLI ranking and earning an SCI of £434. Zanzibar transmits high weights of milk, fat and protein, while also maintaining excellent udder health and good daughter fertility.
Danish VJ Hilario also makes impressive gains, moving from 18th to fourth position, having earned an SCI of £422, and picking up the baton for the Jerseys again.
The leading British Friesian in the top 10 is Catlane Caleb, who is squeezed downwards, having previously ranked second. His SCI of £419 puts him in joint fifth place with the Holstein, S-S-I Headway Alltime and the Jersey, VJ Hoeholt Hilde Huzar (previously ranked 12th and 14th respectively).
Autumn block calving herds looking ahead will find their most profitable choice of sires by using the Autumn Calving Index (£ACI), an across-breed ranking which is dominated, as usual, by the Holstein breed.
Jointly taking the lead with an ACI of £617 are Hoanster Zanzibar and Westcoast Guarantee, the latter making his debut as a daughter-proven bull.
View-Home Littlerock holds his third position with an ACI of £591 while Seagull-Bay SR Stardust rises to fourth from seventh position (ACI £584).
Long-term headliner, Teemar Shamrock Alphabet (ACI £572) drops from first to fifth place, while continuing to transmit the best daughter fertility and TB resistance in the top five bulls.
Reminding producers that the Spring and Autumn Calving Indexes should only be used in tight block-calving herds, Fern Pearston, animal genetics manager for AHDB Dairy says: “These indexes are expressed across breeds, which makes them a particular help to producers involved in cross-breeding, or those considering a change of breed. However, this means it’s very important not to look at the components of the index and compare them with other Predicted Transmitting Abilities (PTAs) used in the calculation of £PLI, as these are each expressed against that breed’s average and on that particular breed scale.”