Dairy bull in a barn© FLPA/Rex Shutterstock

Selecting bulls for efficient feed-to-milk conversion could be worth hundreds of pounds per cow, according to a unique breeding index.

The difference could be as much as £225 over a lifetime, according to Dutch-based genetics company CRV, which launched its Better Life Efficiency (BLE) index in December 2013.

Such a gain assumes a milk price of 30p/litre and works off a cow with a BLE of +5%, which would produce 2.5% more milk for the same amount of feed inputs, Erwin Koenen, lead research at CRV told Farmers Weekly.

See also: Target greater dairy feed efficiency instead of cutting ration costs

He said that Dutch farmers are embracing BLE indexing, alongside the new Breeding Health Index, resulting in bulls rated poorly for these values being harder to market. The two indices are collectively called “Better Life” values.

“This means that farmers do take into account the Better Life values in their breeding decisions,” said Dr Koenen.

BLE expresses the lifetime milk production divided by the lifetime feed intake, with feed efficiency influencing how highly cows are rated.

“What we currently do not know exactly is how large differences in methane production are between animals that eat the same amount of feed,” he explained.

“More research is needed to know what the individual differences are in methane production.”

How the numbers work

  1. A daughter of a bull with +5% is expected to produce 2.5% more milk from the same amount of feed
  2. Over a lifetime milk production of 30,000kgs = 750kgs extra milk
  3. 750 x 30p/kg = £225.

UK version in pipeline

The BLE is a “good initiative” but should only be used to complement production traits, stressed Marco Winters, head of genetics at AHDB Dairy.

“It should be used as an additional tool when selecting bulls,” he told Farmers Weekly, adding that the AHDB was looking at developing a similar index, possibly launching in 2016.

“Our advice, as is the case with all the proprietary indices, is to first select bulls with the right qualities, such as fertility and production traits, and then use an index such as BLE as an additional tool for the last bit of differentiation,” he advised.

Selecting bulls

  1. Select bulls with the right qualities for your operation – fertility, production etc
  2. Use the Breeding Efficiency Index as an additional tool to pick out bulls rating closely
  3. Remember, BLE cannot stand up on its own.