COOPERS® Calf Drench Tips

Are you drenching your calves effectively?

Here are some top tips from COOPERS vet Hannah Field for a successful calf drenching season.

As a rule of thumb, start drenching once calves have been weaned off milk and on pasture for at least three weeks. COOPERS recommend not drenching calves that weigh less than 100kg!


Q: When do calves get worms?

Worms are picked up from pasture once calves are grazing. Therefore, a significant amount of the calves’ diet must be grass before calves are going to have worms. A three-week-old calf on twice-daily milk but kept in a paddock is not likely to have worms!


Q: When should I start drenching calves?

Calves do not need to be drenched until they are likely to have a worm burden. That is not likely to happen until they have been eating pasture as their main feed source for at least three weeks.

  • Before then you are likely to be wasting drench on calves with no worms.
  • Oral drench is designed to be absorbed slowly from the rumen. Drenching calves that are still on milk puts them at risk of toxicity, as drench can be rapidly absorbed from an immature rumen or due to ‘rumen bypass’.
  • Young stock have increased sensitivity to ML/mectin drenches. This includes both oral and pour-ons.

Find out more...

COOPERS vet Hannah Field answers more essential questions about calf drenching this season. Read about it here.

COOPERS Q&A 1       COOPERS Q&A 2       COOPERS Q&A 3       COOPERS Q&A 4

Listen to Hannah’s top tips for calf drenching.