29 September 1995

Later grazing ups worm risk

EXTENDING the grazing period this autumn could expose cattle to increased risk of worm infection.

Dr Peter Orpin of the British Cattle Veterinary Association says that because winter feed stocks are low, many producers are grazing stock for as long as possible.

"Where this is the case, and if the autumn continues warm and wet, cattle will be at risk from parasitic gastro-enteritis (PGE) and lungworm infections," he adds.

Tony Andrews of the Royal Veterinary College warns that once weather conditions are suitable, worms are capable of rapid development into their infective stage.

"Stock in their first, second and third grazing seasons that are still at grass after mid-September will need to be wormed," he says.

The effects of a worm burden may not be seen until next spring because certain species of worm overwinter in the animals stomach wall and will only cause disease when the dormant larvae start developing into adults and laying eggs.

When large numbers of dormant larvae emerge from the stomach wall, severe illness can result.

"Farmers should act on advice from their vet, but generally all younger cattle should be treated with a wormer that will control over-wintering parasites at housing and then treated regularly according to the type of wormer used," says Dr Andrews.

Warm, wet weather will also cause worm infections in pigs.

"Certain species of worm can remain viable in a house for up to five years and my advice is to worm the sow before she is moved to the farrowing house," he adds.

"Also wash her udder with detergent and water to remove eggs which can attach to udder and from there infect the piglets."

Dr Tony Andrews:"Stock in their first, second and third grazing seasons still at grass will need to be wormed."