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Dangers of Encysted Small Redworm in your horse

Encysted small redworm (ESRW) are the larval stages...

Horses / 22.10.2015

Dangers of Encysted Small Redworm in your horse

Encysted small redworm (ESRW) are the larval stages of the small redworm that hibernate in the lining of the gut, which have a tendency to ‘wake up’ in early spring. A mass emergence of these worms can lead to larval cyathostominosis. This can cause diarrhoea and colic in your horse. 

All horses can develop larval cyathostominosis but those that may be particularly vulnerable are youngsters, old or immune-compromised horses, those with an unknown or sub-optimal worming history and those that were not dosed correctly in late autumn/early winter.  In fact there is a mortality rate of up to 50%. However this risk can be managed with a timely worming programme.

Many horse owners think that the wormer they are using treats for small redworm but are unaware that not all wormers will have any effect on the encysted stage. It is also commonly confused that if a faecal worm egg count comes back clear then they do not need to treat the horse. As any encysted stages would not show in the count a treatment for this would be recommended in late autumn/early winter.

For more information you can contact our knowledgeable AMTRA qualified team or read more about the problem at www.esrw.co.uk/