THE TREND towards ever bigger dairy cattle, might have to be arrested to ensure better efficiency in the herd.

For many years, bit cattle meant big yields, but farmers attending a recent AHDB 'Calf to Calving' meeting held in Aberdeen, were told that it was time to stop the rise in stature and instead look towards types which would maximise efficiency.

The AHDB's dairy technical manager, Andy Dodd, explained that a 'maintenance value' had been added into the most commonly used breeding indices to try and stop UK dairy cattle getting any bigger. In time, this should see fewer huge cows being bred.

While breeding indexes such as the Profitable Lifetime Index (£PLI) and the Spring Calving Index (£SCI) have included key traits such as fertility, longevity and production, maintenance has been a more recent addition. Using the genetics of the sire, it estimates the mature weight of its daughters compared to the average heifer, which means farmers should be looking for a negative result.

Mr Dodd said: “We don’t necessarily need cow size to reduce, we just need them to stop getting bigger and bigger. The maintenance value will estimate how far above or below the average weight the daughter of the sire is likely to be. To keep size at reasonable levels, we want farmers to select those which are likely to be lighter than average.

“Maintenance is really about efficiency. Historically, farmers bred bigger animals to produce more milk, but we know smaller animals can produce just as much, so often bigger cows simply cost more to feed.

"There is also a concern on many farms about cows outgrowing the cubicles in both sheds and parlours and incurring extra costs there,” he pointed out.

He stressed, though, that understanding your herd and production requirements is key to getting selection right. “For dairy farmers working on contract, they will generally need to select for volume, fat and protein. However, the criteria processors are looking for can often vary hugely so producers really need to tailor their cattle breeding plans to their system.

"Other producers may be looking to improve the health of their herd and so should be prioritising things like fertility, lifespan and somatic cell counts.”

He pointed to AHDB Dairy’s website tool, which allows farmers to create a herd genetic report for their farm. This identifies the genetic strengths and weaknesses in an individual herd, to help farmers tailor their breeding choices.

They can then use the AHDB Dairy Breeding+ webpage to compare bulls and traits from across the UK. Farmers pick their preferred breed and then search for the key criteria they are looking for, whether it’s high milk production, specific fat and protein levels, or a combination these and other traits. They will then be presented with all the bulls in UK which meet those criteria.