1 August 1997

Keep calf growth going

GROWTH rates of newly weaned autumn-born calves must be maintained by supplementary feeding to achieve the heaviest animal possible at autumn sales.

Target gains for autumn-born calves are 1.1kg/day for steers and 1kg for heifers, according to Signet consultant David Evans. To sustain this rate, calves should be turned onto fresh grass with sward heights of 8-9cm (3-3.5in). "At this height the optimum balance between grass quality and calve intakes is struck and growth rate, therefore, maximised.

"However, grass quality is beginning to decline and so to sustain target growth rates autumn-born calves should be fed concentrates at grass. Calves which will be overwintered should be offered 2kg/day, and calves destined for autumn sales should be fed 3kg/day," he says.

For calves which have not been offered creep, Mr Evans advises introducing feed at 0.5kg/day and gradually increasing rates.

&#8226 Calf growth rates are at particular risk from worm infestations, reports SAC vet Brian Hosie. Boluses administered at turnout could run out before cattle are taken off grass and may leave cattle unprotected in a year when warm, wet weather could lead to high worm numbers.

He advises consulting vets on how best to prolong treatment.