Treating a heavy worm burden

Watch out for colic and shedding gut lining. It can be traumatic for them.
 
Mine were treated in October - but then rather than waiting until March were wormed again on the 12 week mark......

My mare on this regime had a zero worm count from a poop count - but blood tests revealed tape worms, so she was given a double dose by the vet because of her colic.

If they have worm burden then worming can, as Wally says, bring on colic. Keep them in for 24 hours after worming so they aren't on the paddock.
 
The method that I use if they are very poor, (I think it came from one of the rescue homes) is to start with the mildest wormer possible (I use panacur) use that once a week for four weeks and then step up to something like StrongidP monthly, doubling the dose on the second month to do tapeworm and only them go for a stronger wormer to get the encysted redworm.
 
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