25 September 1998

Growth rate justfies higher feed costs

ACHIEVING heavier weights in a shorter time would be possible by improving store rations and by feeding harder to finishing at Meads Farm, Ixhill, Oxon, according to ADAS senior livestock specialist Elwyn Rees.

"We have been too obsessed with the idea that heifers will grade too fat. Peter Hawes has access to exceptional cattle genetics, which underlines the importance of breeding. He could push them harder as stores and finishers.

"When heifers are in their store phase, they need to grow at 0.6kg/day. This year they achieved lower gains, and were therefore slow to finish.

"This was because there was insufficient protein in the store ration, which affects forage digestion. The proprietary concentrate could have been fed alone, allowing growth rates to increase partly because of forage digestibilty," the Oxon-based specialist says.

This would have cost an extra £7-8/head over the 180 day store feeding period. But increasing growth rates by 0.1 kg/day, resulting in an extra 18kg of weight would justify the additional feed cost, says Dr Rees.

"When heifers move to the finishing phase its worth adding more barley to the diet, increasing energy. This will allow animals to finish and grow at 1kg/day.

"By pushing them harder in both phases Mr Hawess heifers could reach a heavier weight two months earlier than last year," he adds.

Heifer finishers must start with good genetics, while Continental blood helps as they are slower maturing and less liable to lay down fat at heavy weights, explains Dr Rees.

"Diet is important; its a fine line between getting it right or wrong. Where theres too much protein in rations, animals can turn fat because theres too much energy, which converts to fat.

"Likewise, where theres not enough protein, there will be a shortage of amino acid meaning lean muscle isnt created."

Compensatory growth is important to maximise gains during the finishing phase, says Dr Rees. "The object is to hold growth back during specific periods of the year. Spring-born calves are often fed store rations in their first winter, ideally aiming for growth rates of 0.6kg/day for heifers.

"Once they are turned out in spring, growth rates could then be as high as 1.6kg/day, depending on grass quality. Finishers shouldnt be afraid to supplement animals at grass where they arent performing.

"Check performance by weighing and monitoring regularly, but use this information and act accordingly," says Dr Rees. &#42

HEIFERFINISHING

&#8226 Heavier weights.

&#8226 Good genetics vital.

&#8226 Balance rations.