Animals on 16 dairy calf to beef farms which took part in a study on anthelmintic resistance were 100% resistant to Ivermectin, a joint Teagasc-UCD study has found.

Anthelmintic resistance is where worms in an animal survive a dose of wormer which would normally kill them.

Resistance to levamisole and moxidectin was also detected on two (18%) and eight (73%) farms respectively, with the authors concluding that anthelmintic resistance was widespread on the sampled dairy calf to beef farms in Ireland.

Urgent measures

“Sustainable worm control strategies, such as grassland management and targeted treatments, which prolong the lifespan of the currently available anthelmintics need to be implemented as a matter of urgency,” the authors said.

The study was carried out on 23 dairy calf to beef farms, with faecal egg counts carried out every two weeks.