15 March 2002

Feed to match high yield cows

MOST herds culled out during the foot-and-mouth outbreak are being restocked with higher yielding cows and producers must change their feeding management to match.

Restocking is providing an opportunity to increase herd milk output, says independent dairy consultant and Keenan adviser David Jacklin. "Herds previously yielding about 6000-7000 litres are being replaced with cows yielding an extra 2000 litres."

But the existing grass silage plus 1.25t a cow of parlour concentrate system on many of these units is inadequate to maintain this higher level of milk production. "However, it is possible to achieve these higher yields without having to resort to a complex feeding system."

The aim is to supply sufficient energy while making full use of grass to minimise costs. Consider grouping cows at grass with autumn calvers in one group on grass alone, while fresher cows are buffer fed to boost intakes, says Mr Jacklin. "Some advisers believe feeding high yielding herds involves lots of groups and rations. But a single mixed ration for milking cows, while housed, keeps the system simple and avoids milk yield loss when moving cows."

For winter rations, an additional forage to grass silage is essential, such as whole-crop cereal or brewers grains. While maize silage can be grown in Cumbria, he believes whole-crop may prove a more reliable option for many northern producers.

Even with mixed forages, higher levels of concentrate feeding will be necessary to maintain milk output. But the risk of acidosis will be greater, particularly when it is fed in the parlour, says Mr Jacklin.

"Including structural fibre in the ration, such as straw, will reduce this acidosis risk. Maize silage only rations require about 1kg a cow of straw, while those containing a high quality grass or whole-crop silage only require 0.4kg a day." &#42

A single mixed ration for milking cows, while housed, keeps the system simple.