Is drench resistance a problem on your farm?

Is drench resistance a problem on your farm?

Producers in and around Casterton are invited to an upcoming livestock health and biosecurity workshop focusing on the big issues in the region, such as on-farm drench resistance. Producer-led extension team, Stock Sense, have put together a stellar program giving attendees the opportunity to have their questions answered by industry professionals.

As for drench resistance, Stock Sense veterinarian, Dr Patrick Kluver, claims that “unless you’re testing for it, you can’t tell if you’re dealing with a resistance problem. In most cases the effect that worms have is subclinical; appetite suppression resulting in a decrease in weight gain in young cattle. We’ve been using the same drench class in cattle, mectins or macrocyclic lactones (ML), for the last 30 years therefore resistance is inevitable.”

Surveys of the high rainfall zones of Victoria show that around 76% of farms have emerging resistance issues, with around 20% of farms registering resistance to the most dangerous or destructive worm Ostertagia.

“Resistance to Ostertagia is the most concerning development, as it has potential to cause severe production losses and can cause a disease called type 2 Ostertagiosis. This condition can result in permanent damage to the gut. There are increasing reports of this condition now and part of the problem may well be the reduced drench efficacy with the emergence of resistance” said Dr Kluver.

It is not all doom and gloom as there are strategies you can use to keep resistance out and reduce the development of resistance.

To hear more on drench resistance and other topics join us at the upcoming workshop in Casterton which is free for all producers to attend and will include a light lunch.

For a detailed program and to register visit or contact Stock Sense on 1300 020 163 or

Stock Sense helps livestock owners adopt animal health and production practices that improve profitability, animal welfare and Victoria’s biosecurity status. The producer-led extension projects are funded by the Cattle, Sheep and Goat Compensation Funds, and proudly delivered by VFF Livestock for the benefit of all Victorian livestock owners.

Source: Stock Sense