Worming and Parasites

Let’s Talk About Tapeworms!

Let’s Talk About Tapeworms!

The tapeworm is a danger to horses and, of the 3 tapeworm species affecting horses in the UK, the most common is Anoplocephala perfoliata. This pale-coloured parasite has a flat, segmented body and when it’s fully grown it measures up to 80cm in length.

Unlike other types of parasitic worms, tapeworms develop inside an intermediate host – the microscopic forage mite. Horses become infected when they eat hay or grass containing these mites, which are themselves infected with tapeworm larvae. These then move on and develop into adult tapeworms inside the horse’s intestines.

Once laden with eggs, segments of the tapeworm’s body detach and are passed out of the intestines in the horse’s droppings. The eggs are then released into the pasture and ingested by forage mites. The lifecycle takes from three to six months to complete and, due to our temperate climate, the UK’s horses are particularly susceptible to tapeworms. Some horses are more prone to infection than others, in fact, 80% of intestinal parasites reside within just 20% of the equine population. While young and geriatric horses are at greater risk from heavy burdens, tapeworms can be hidden within any animal. What’s most worrying is that an apparently strong healthy-looking horse can be harbouring a large build-up of these potentially lethal visitors.

Research at the University of Liverpool revealed that 80% of ileal impaction cases and 22% of spasmodic colic cases were due to tapeworms. Therefore, ensuring your horse is free of tapeworms will reduce the risk of colic.

Diagnosing tapeworm in live horses is difficult. Even if you don’t find tapeworm eggs in faeces, it doesn’t always mean that the horse is free of tapeworms. Egg counts alone are not reliable in the detection of tapeworm. Saliva testing such as the Equisal Tapeworm Count Kit and the ELISA blood test check for tapeworm antibodies rather than eggs. This is a far more reliable method, but even that isn't 100%.

Additionally, it is important to be aware that not all wormers kill tapeworms. However, the tapeworms can be successfully treated with one of two drugs – praziquantel and pyrantel, and remember, pyrantel needs to be a double dose. Fortunately, both drugs are very effective and cause death and detachment of the tapeworms from the gut wall within 24-48hr following treatment. They are available as single products or in combination with other drugs that target different types of worms. Parasite populations on the pasture can be reduced by regular removal of droppings, resting grazing and rotating sheep and cattle on to horse fields.

At Farm & Stable, we recommend following a programme of Spring and Autumn worming for your horse, including specific wormers for Tapeworm. Don’t forget to also include a probiotic for 7 days such as TRM Synbiovit during any period of worming.

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