The only available vaccine which protects against lungworm in cattle is to be withdrawn from the market.
Bovilis Huskvac is an oral vaccine which is given to calves prior to turnout in the form of two doses four weeks apart.
The manufacturers of the vaccine, MSD Animal Health, have confirmed that it will be discontinued from the end of 2027, so it will still be available next season.
Recued wormers use
At an online event on Monday, Lancashire-based vet Rob Howe, described Huskvac as a “very, very useful product” as it allows farmers to reduce wormer use.
He explained that lungworm tends to be a bigger issue in the first grazing season for dairy-bred calves than it is for suckler calves.
He said adult cattle should have immunity to lungworm, so they shed fewer eggs which slows down contamination in pasture.
“When mothers are with their calves, they act as hoovers. If we only keep calves together, they are little mini factories for parasites,” Howe said.
For cattle to develop and retain immunity to lungworm, they require a certain level of exposure to the parasite.
It is a key reason why animal health experts warn against the over-use of wormers, as it can lead to young cattle being naïve to lungworm for longer.
Another reason for avoiding over-use of anthelmintics is it can lead to a build-up of worms in pasture which are resistant to wormers.
“If a farmer has been using the same [wormer] product every year, that is quite a good way to generate resistance to the product,” Howe said.
Dung beetles
Anuschka Marsman, who is a vet based in Wales, said wormer use can also have an impact on dung beetle populations in grassland.
She described dung beetles as “a farmer’s best friend” as they have a role in dispersing dung, recycling nutrients, improving soil health and reducing pest populations.
Marsman outlined results from a survey of local livestock farms which found “big differences” in dung beetle populations.
“Low numbers and diversity [of dung beetles] was linked to use of long-acting wormers,” she said.