History of worm control

We have helped develop two methods of providing grouse with an anthelmintic (worming drug) to kill worms:

  • Catching grouse at night and treating them with a levamisole hydrochloride oral drench anthelmintic (trade name Nilverm). This, however, proved labour-intensive and unsuitable where terrain made night access difficult and dangerous.

Direct dosingPrevious ‘direct dosing’ methods were labour-intensive and impractical in certain conditions.

  • An indirect method, involving a grouse’s requirement for quartz grit in their gizzard to aid the digestion of its fibrous diet of heather shoots, which make up 80% of the diet. Grit can occur naturally on moors but is also provided by gamekeepers. Grouse consume approximately 35g of grit per month. For reducing worms, quartz grit is used that has been treated with a thin covering of fat into which an anthelmintic drug is impregnated. This is known as ‘medicated grit’.

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Medgrit1What's inside your FREE guide

✓ History of disease
✓ History of control
✓ Medicated grit
✓ Assessing grouse for worms
✓ Deployment of medicated grit and grit box hygiene
✓ Best practice checklist

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Free Medicated Grit Guide



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