Giving first season grazing calves a lungworm vaccine before turnout will protect them against potentially lethal disease and reduce any economic losses due to ill-health, according to the Control of Worms Sustainably (COWS) group.

“There is no way to predict easily when lungworm will hit and waiting until coughing starts later in the season is less than ideal,” says Rob Howe, a COWS member and vet working for LLM Farm Vets based in Preston.

“Using a preventative vaccine should allow farmers to relax about what is arguably the most serious risk at grazing to youngstock. Animals suffering from excessive gut worms
can lose weight and scour, but there is likely to be plenty of warning before things get too serious.

“In a project where I worked with 30 clients reviewing their worm control, lungworm vaccination was one of the things I strongly encouraged. Most farmers did vaccinate – but in the small number that did not, half went on to see clinical lungworm in their calves.”

Cattle can be given an oral vaccine containing irradiated lungworm larvae (L3) which stimulate immunity. This is given in two doses four weeks apart to animals over the age of eight weeks old. They must then not be exposed to any lungworm larvae for the next two weeks.

This means farmers should count the weeks back from the expected turnout date and place orders for lung worm vaccine now.

After vaccinating, calves should be turned out onto low level infected pasture to boost their immunity naturally, ie not clean pasture or where previous heavy use of gut and lungworm wormers has removed all larvae from the fields.

“Lungworm outbreaks can cause severe losses and even death in cattle,” says Mr Howe. “Calves that recover from lungworm disease rarely go on to reach their full potential in terms of milk production and remain poor doers.

“All farms, and particularly those with a previous history of lungworm, should consider vaccination as an integral part of their overall worm control strategy.”

For more information on preventing and treating lungworm in cattle visit the COWS website: