Horse dies suddenly due to serious worm damage

An equine vet is urging horse owners to maintain responsible worming programmes – following the sudden death of a seemingly healthy horse.

Kirsty MacGregor, of Bakewell Equine Clinic in Derbyshire, was called out to examine a six-year-old horse which had suddenly dropped dead in the field. The animal had appeared outwardly health and had had relatively good body condition.

A post mortem examination found that the cause of death was a fatal blood clot caused by severe worm damage, known as ‘verminous thromboembolism’.

Ms McGregor explained: “The large intestine was loaded with larvae and there was evidence other worms had migrated to the arteries and the liver, causing inflammation and damage. The horse also had lesions in the small intestine.”

The horse was kept on a large DIY yard with around 40 horses and ponies. With so many individual owners, it had proved difficult to implement a regular worming programme.

Following the horse’s sudden death, Ms McGregor and her colleagues carried out emergency dosing of all the horses on the yard and put together a worm control programme for all the horses.

Ms McGregor added that she had seen a number of cases involving small redworm infestation this year – with symptoms including violent colic and weight loss which, in some cases, have proved fatal.

She said: “These unfortunate cases serve to highlight the tragic consequences of being unable to coordinate an effective worming programme.”

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