Drench checking

Faecal egg count under the microscope - Photo from Gribbles

Faecal Egg Count data obtained across the Gribbles Veterinary network for the season 2021-2022 shows a rapid rise in the prevalence of anthelmintic resistance in dual and triple-active drench categories when compared with the previous report in 2016-2017 (McKenna, 2018). The landscape of anthelmintic resistance is continuously changing, due in part to the variation of active combinations available and in use.

Do you know whether that drench you just used is working?

Your stock may look to be free from signs of parasitism, but a drench can have lost a significant amount of its efficacy before you notice any clinical impact. Continued use of a poorly effective drench is a perfect recipe for building up high levels of resistant parasites.

So what can you do?

A drench check is a faecal egg count performed after drenching to confirm that the product has actually worked. A drench check is typically done 7-10 days post drenching. 

Your weaning drench would be the ideal opportunity to do a check, as it is early enough in the season that you will obtain the full spectrum of worm species whilst allowing time to make changes for the rest of the season or investigate further if the result is questionable.

A drench check should be performed at least once a year. This way any potential issues can be detected and addressed before your property may have been contaminated with vast numbers of resistant parasites.

So, next time you pick up your drench ask us for some pottles. You then collect 10 faecal samples & get them back to us for testing. These can be taken from the paddock so long as they are fresh. We can have the results to you within 24-48 hours and give you more confidence when making your drench choices.

With drench resistance a serious emerging issue that has significant production-limiting effects, you cannot afford not to have this information.

Our team can help you slow down the development of drench resistance on your farm by discussing the appropriate management options, as well as the drench options for your farm. For practical parasite management solutions, speak to one of our team.


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