Search Results
<  Back

News & Updates

New regional resistance data helps producers select the right sheep drench

Choosing the right drench is now easier for Australian sheep producers thanks to a new data tool from Virbac Animal Health. The Tridectin Drench Efficacy Portal will allow producers to compare drench effectiveness in their region based on the latest Faecal Egg Count Reduction Testing (FECRT), helping to protect their bottom line.

 Virbac’s Technical Service Manager and vet, Dr. George Cox, says the portal aims to assist sheep producers in effectively managing worms in across their sheep operations. “Our goal was to provide sheep farmers with a user-friendly tool that can help them make educated drenching decisions using the most recent FECRT data”.

Collected between 2018 and 2022 across 76 FECRTs, the data available on the portal is summarised as per Wormboss regions. Seventeen actives or combinations of actives, including triple, dual, and single active formulations were used in the tests.

 While the portal provides the most recent and relevant data, Dr. George Cox reminds producers that every farm is different, and the best way to select the most effective drench for their sheep is to undertake regular FECRTs on their properties.

 “Every time we drench, we select for resistant worms. This is why we recommend testing sheep flocks for drench resistance every 3-5 years.

 “Regular testing assists advisors to design appropriate drenching programs to effectively control worms, and, more importantly, secure the effectiveness of drench actives in the long term”. 

 “The data we have collected to date, which is accessible via the portal, has provided some interesting results and we will continue to add new results as we collect them” says Dr. George Cox. 

 Producers and advisors can access the average overall broad-spectrum efficacy on a national and regional basis.  Barber’s pole worm, Black scour worm, and Small brown stomach worm efficacy can also be viewed nationally or regionally in the portal.

 Results on the portal show that Tridectin, with its unique Moxidectin triple active formulation, is more effective than most other drench combinations with a 98% overall efficacy. It outperforms Abamectin-triples and competes well with Monepantel/Derquantel combinations, offering the same power of worm control. Tridectin was also the most effective drench against Barber’s pole worm with a 97.3% average efficacy and its inclusion should be considered in most drench programs.

 Tridectin’s superior efficacy has been attributed to its unique combination of Moxidectin, Albendazole and Levamisole, which provides persistent activity for 14 days. It can be used across ewes, lambs, and rams at any time of year, and has a short meat withholding period of 7 days and export slaughter interval of 17 days. Tridectin is not suitable for sheep that are, or may, produce milk or milk products for human consumption.

 To try the portal visit Those who use the portal and enter their data before 31st December 2022 will also go into the draw for a chance to win a drench resistance test on their farm.