5 July 2002

REPLACEMENTHEIFERS – BEING COST AWARE…

The cost of rearing replacement heifers varies between

herds by £190/head, but how do you ensure your

youngsters are not too costly. Richard Allison

reports from a low cost rearing system

REARING dairy heifers typically costs about £20,000 a year for a 100-cow herd, but one West Sussex producer is managing to rear heifers at two-thirds of this cost.

The key factor in minimising rearing costs is to keep the system simple, requiring little labour, says Pete Dutton. "At Woodwards Farm, feeding heifers self-feed clamp silage means only 10 minutes is required daily to move the fence and top up feeders. Bedding with straw takes an additional two hours each week."

Costs are kept low from birth with calves only receiving colostrum and stored waste milk. This eliminates the need for any milk powder. Technical director of the Kingshay Farming Trust, James Hague estimates that this saves about £18/calf in milk powder costs.

Calves from Mr Duttons 380-cow herd are housed in starter pens with free access to a small grazing paddock from 4-5 days of age, says Mr Dutton. "Having plenty of fresh air means pneumonia is rarely seen and animals are fitter outside, helping to maintain calf survival rates at more than 97%.

"Allowing access to grazing from an early age also boosts growth rates to more than 1kg/day, higher than when on winter feed. Having calves out in winter was my wifes idea. Its more welfare friendly and our fields are sheltered by trees."

Mr Dutton also believes heifers have more respect for fences and gates when turned out at an early age. "They tend not to push on fences, cutting the hassle of escaping animals. However, care is needed to ensure they have access to water troughs. Waste tarmac was laid to raise the area around water troughs so calves can reach."

Calves are weaned in batches at 6-7 weeks of age. Weaning is easy to manage as the herd has a compact 12-week block calving pattern, with replacement calves born over a three-week period in late summer. This three-week calving period is achieved by inseminating the first 200 cows with New Zealand Friesian semen; remaining cows are served by a sweeper bull.

"Heifers fit in well with the grazing system being used. They clean up grazing swards in October after cows are housed for winter. There is often a lot of grass left and heifers cause less damage than cows, which is useful when grazing heavy land."

Before grazing these paddocks, calves are wormed with an avermectin-based wormer at 3.5 months of age due to the worm challenge from the cow grazing paddocks, explains Mr Dutton.

Heifers are normally housed in late January and fed straw plus 2.5kg of a standard 16% crude protein, low energy nut. Animals are turned out in mid-March onto maize ground undersown with ryegrass for early bite. From August, they also receive 1kg/day of maize gluten feed.

"During the second winter, heifers have self-feed silage with concentrates. When silage quality is good, they receive no concentrates minimising feed costs."

To calve at 24 months of age, heifers are housed and served in mid-October. As with cows, heifers are inseminated with NZ Friesian semen for the first three weeks, then a sweeper bull is brought in.

This helps to keep the calving period compact and may help improve fertility, herd conception rates currently stand at 55% to first insemination, says Mr Dutton.

Calving heifers at 24 months instead of three years cuts rearing costs by £189/head, says Mr Hague. "For producers with seasonal calving patterns, animals missing the 24-month target have to be kept a whole extra year."

Average replacement costs at Woodwards Farm are £651, which equates to 2.5p/litre. He believes replacement costs are as high as feed costs and should be acccounted for in herd costings.

Cow longevity is an important factor in dairy herds with most cows being culled due to poor fertility, says Mr Dutton. "But heifer culling rates are low at 9%, less than the average of 15% for Kingshay recorded herds. We seem to be managing to get heifers back in-calf during their first lactation."

He believes the key to good heifer fertility is getting heifers well grown and in good condition before first calving.

This is reflected in recent Kingshay research which shows the optimum weight at bulling is about 380kg, says Mr Hague. "For more Friesian-like animals as at Woodwards Farm, the optimum weight is lower at 340kg."

&#8226 Keep system simple.

&#8226 Autumn grazing.

&#8226 Check growth rates.

The secret to low cost heifer rearing is keeping the system simple to minimise labour requirements, says Peter Dutton.