By Farmers Weekly staff

SHEEP producers shouldnt be tempted to keep culls despite the turmoil in sheep markets this autumn.

Sheep consultant Lesley Stubbings warns that cutting replacement costs by keeping old ewes will cut profits in 2000.

“Output is the major determinant of profitability even when lamb prices are low, so keeping old ewes is false economy,” she says.

In lowland flocks, about 8% of ewes fail to rear lambs due to infectious abortion, deaths and barrenness.

For every 1% increase above this level, the cost of production will increase by 6-7p/kg deadweight lamb produced when all costs, including overheads, are taken into account.

“Old ewes are less likely to rear lambs, so keeping them could mean the difference between loss and profit on every kilogram produced.”

Reducing the number of unproductive ewes in a flock will also help, she says.

“Infectious abortion is the main cause of this, and on average affects 3.5% of ewes. Eliminating this loss would reduce the cost of production by 8.5p/kg.

“In flocks where abortion affects 10% of ewes, the additional unit cost is over 40p/kg, which would push most flocks into a loss.”

To safeguard profits, she advises taking advantage of low replacement costs to ensure that output next year is maximised, while inputs, such as replacements, quality feed and vaccinations should be viewed in terms of cost benefit.

“Improving output of lamb produced a ewe is the ultimate target; dont jeopardise your chances of making a profit for short-term savings,” she adds.