26 October 2001

Get nutrition right & it all follows on

By Hannah Velten

CORRECT winter nutritional management of beef replacement heifers is critical to ensure early mating, reduce rearing costs and improve lifetime production.

According to Meat and Livestock Commission beef scientist Duncan Pullar, producers should aim to serve heifers at 15 months to calve at two years. "Calving heifers at three years means they are producing nothing for a year, costing about £63/head in wasted feed."

In general, bulling heifers should weigh about two-thirds of their mature weight at service, adds Dr Pullar.

According to Hants-based Signet consultant Ian Ross, most spring-calving beef herds aim to bull home-bred heifers at about 400kg in May-June. "To achieve this weight by 15 months, heifers must keep growing, particularly through weaning when growth checks can occur."

As calves, heifers should be growing at 1kg/day on their mothers milk but should be offered creep feed ad-lib a month before yarding/weaning at 200 days old.

"They should be eating up to 2kg/head of creep prior to housing, which must be continued for a few weeks once housed.

"The stress of weaning will increase calf susceptibility to pneumonia so prevention is critical and they must be wormed before or after housing," he adds.

Over a 180-day winter, a reasonable growth rate of 0.6kg/day should be the aim, with a target of 350kg at April turnout. This growth can be achieved on ad-lib 10.5ME, 14% crude protein silage and 2kg/head/day of barley.

Ideally heifers should be weighed to gauge whether growth rates are on target, advises Dr Pullar. "Girth measures are no substitute for a proper weighing system," he adds.

After Christmas, if heifers are growing faster than expected, barley can be cut out, adds Mr Ross.

Heifers should not be allowed to become over-fat as this will reduce their lifetime milk output, says Dr Pullar. "Check condition scores. When heifers hit weight targets but are over-fat, the breed may not have the growth potential for what you are feeding," he adds.

In-calf heifers at their second housing should be fed on ad-lib silage up to two months before calving, then restricted to 20kg/head/day of silage and ad-lib straw in the last six weeks of pregnancy to avoid calving problems, advises Mr Ross.

Replacement bulling heifers in autumn-calving herds should not be mated at housing, says Basil Lowman, SAC beef specialist.

"Mate well before or after housing, not at housing, which causes too much stress." &#42

"A month before housing they should be trough-fed 1kg/head/day of cereals, purely to quieten and acclimatise them to human contact, and given a long-acting wormer," he adds.

Their winter ration of ad-lib silage and 0.5-1kg/day of cereals should support growth rates of 0.7-0.75kg/day, but one month after mating, if heifers are too fit, their ration should be reduced so they are on the lean side of fit at turnout.

REPLACEMENT HEIFERS

* Bull at 15 months.

* No growth checks.

* Fit not fat.

Avoid beef replacement heifers becoming over-fat during growth as their lifetime milk output will be compromised, says Duncan Pullar.

HOWTODOIT

&#8226 Bull at 15 months.

&#8226 No growth checks.

&#8226 Fit not fat.