Tony Rhodes, who has spent much of his career helping farmers outsmart internal parasites, says sustainable parasite management is the sum of many different actions on farm – and people can start that journey at any time.
This three-minute survey will tell you how you’re tracking. How many of the 6 questions do you answer 'yes' to? Check your results below the survey.
How did you score? (Total number of 'yes' answers)
5-6 You have a good handle on internal parasite management.
3-4 Your operation would benefit from some farm-specific advice.
0-2 You need to make changes, for the long-term health of your operation. See below.
The first four steps
After 40-plus years of working with farmers, these are Tony’s four steps to gaining the upper hand:
- You need to know which active ingredients work on your farm – and that means carrying out a faecal egg count reduction test (FECRT) every three years.
Talk to your vet or drench retailer for help in doing this. There’s no avoiding step 1. - Select and use effective combination drenches.
The FECRT will tell you which active ingredients are effective on your farm. Use these in combination as your core drench programme. You can monitor how well these products are working with a drench check test. Again, talk to your vet or drench retailer for guidance. It seems obvious, but don’t buy your drench based on price alone or free giveaways. - Manage contamination of pasture and reduce the level of reinfection of young stock.
How? By using a fully-effective drench and maintaining a tight 28-30 day drench interval for lambs and dairy-bred calves through until autumn. Do not extend drench intervals, because stock appear to be growing well or it’s dry – that only creates a problem later in the season. It appears counter-intuitive, but do not drench lambs/calves based on faecal egg count – instead front foot it and work to the 28-30 day interval, regardless. - Identify and reduce the high-risk practices that speed up drench resistance.
Specifically, avoid using long-acting drenches, capsules and routinely drenching adult stock. If you are drenching lambs/calves onto new grass or crops, then you must have a follow-up plan to ensure refugia. Seek advice on how to do this – it’s easy.
Is that all?
If you do nothing other than tick off those four steps, you’ve still put your operation in a much stronger position.
However, if you do want to go further, you certainly can. It’s a case of adding in additional tactics that work to (a) strengthen your management of parasitism and/or (b) reduce the development of resistance.
For instance, you might head along to a Wormwise workshop and come away with a grazing management plan designed to keep lambs’ and calves’ exposure to parasites low.
Or you could identify “priority’ and “low risk” classes of stock and build a targeted selective treatment approach into your drenching programme, whereby you leave a proportion of robust stock undrenched to help ensure successful long-term management of internal parasites. Again, this is covered off in the Wormwise workshops.
Final word of advice
Tony: “You’ll only regret the planning you didn’t do. Developing a parasite management plan for your own farm will take a bit of time, but will be very rewarding.”
Resources for farmers
- Wormwise website
- Wormwise handbook
- Request a printed copy of the Wormwise handbook
- Request a Wormwise workshop in your area: Contact your B+LNZ extension manager
- Podcast with Dr Dave Leathwick: Hear Dr Leathwick talk about good management practice for internal parasites and answer farmers’ questions
- Worms in refugia - a tool to delay drench resistance
