5 December 1997

Fertility problems can be overcome

HIGH genetic merit dairy cows can be just as fertile as their lower merit contemporaries when fed and managed well.

That is the view of UKdairy vets Neil Howie and David Whitaker, who compiled the latest of the Dalgety/Holstein Friesian Society high genetic merit initiative position papers Managing Fertility in High Genetic Merit Cows.

Both accept that poorer fertility may be associated with high milk yields, but stress that the main cause is inadequate feeding and management, which can be overcome.

"Feed and manage top performing cows correctly and they will be every bit as fertile as any other animals in the herd," says David Whitaker of the University of Edinburgh. "More than anything else, good fertility depends on good nutrition in late pregnancy and early lactation."

High genetic merit cows are well known to be at greater risk of condition loss in early lactation as a result of more efficient partitioning of energy into milk production. The aim, therefore, is to ensure the best possible energy balance in the dry period and in early lactation, says Mr Whitaker. "Placing the management emphasis on feeding for late pregnancy and early lactation energy balance is likely to be far more rewarding than chasing largely unproven links between fertility and protein, mineral, trace element and vitamin supply," adds Neil Howie of Nantwich-based Wilson McWilliam Partners.

Both vets advise feeding a mixture of the best conserved forages ad lib to all cows in the last three to four weeks of pregnancy, and supplementing the forage with 2-3kg of a dry cow concentrate to increase the energy density of the diet.

They also advise against changes in diet at this stage or after calving, and suggest providing plenty of fresh forage and water around calving and in early lactation. &#42

David Whitaker:

Good fertility depends on good nutrition in late pregnancy and early lactation.