1 October 1999

Post-calving drench

OVERCOMING low intakes in newly calved cows is notoriously difficult. Cows are pushed into a state of negative energy balance making them vulnerable to metabolic disorders, but a new drench administered six to 12 hours after calving could help.

The GLW rumen auto-drench system, launched by Geo L White at the dairy event, is a blend of minerals, trace elements, vitamins, yeasts, glucose, enzymes and other nutrients delivered through a specially developed drenching machine.

Independent dairy consultant, Hamish Anderson explained how it works. "In newly calved cows, the rumen is contracted meaning intakes are low. Normally, it takes several weeks for the correct rumen bugs to establish, permitting higher intakes.

"Drenching with this system expands the rumen and enables the correct rumen bugs to thrive. This means intakes in cows three days after calving are on a par with those normally achieved three weeks after calving."

In a trial at CEDAR, milk yields of drenched animals and those not receiving the drench were compared. In treated animals, total milk yield between weeks two and 20 of lactation was 310kg higher than in untreated animals, equating to £60 worth of extra milk, said Mr Anderson.

Preparing the drench involves mixing a sachet of powder with 500ml of propylene glycol and 35-40 litres of warm water in a tank. The tank is attached to a purpose designed, battery operated dosing machine.

"Cows can readily be drenched in a crush, with the drench taking about two minutes to administer," added Mr Anderson. The dosing machine costs £285 and the drench, £8.50 a cow.