Fast moving snails spread deadly dog disease across UK

Despite their lethargic reputations, snails can travel at a relatively speedy one metre per hour, say researchers.

By attaching multicoloured LED lights, the scientists were able to track their movements over a 24-hour period.

The gastropods were fast enough to explore the length of an average UK garden in a single night.

But scientists are worried that the fast moving snails are spreading a parasite that is deadly for dogs.

Over the past few years the wet summers enjoyed across the UK have proved the ideal breeding grounds for snails.

According to the Royal Horticultural Society, their numbers increased by 50% last year.

As well as being a pest for gardeners, snails can also spread a parasite called Angiostrongylus vasorum.

This lungworm is a particular threat to dogs, which can become infected by accidentally eating slugs or snails which they come across in the garden or on dog toys.

Painted snails
To assess the scale of the threat, researchers at the University of Exeter decided to track the movements of snails in garden situations.

To do this they attached tiny, multicoloured LED lights to the backs of some 450 snails and used UV paint to track their movements.

The researchers found that the snails could cover distances up to 25 metres in a 24-hour period.

"They are so slow that people don't even think about them moving, but it turns out they do, and they can go a long way in a night," said Dr Dave Hodgson, who lead this study and was also involved in a BBC amateur science experiment in 2010 that sought to discover if snails had a homing instinct.

The researchers say their new work indicates that snails pose a growing threat to pets.

"They are not just lettuce munchers, they are carriers of parasites that can kill your dogs," said Dr Hodgson,

A recent survey of veterinary surgeons indicated that the lungworm parasite was now endemic across the UK, where once it was mainly found in the south.

"It is becoming a real problem not just in the south of England, it is moving north to Scotland," said Dr Hodgson.

"It is a national problem and we all have to pay attention to the interactions between dogs and snails," he said.

Happy trails
In the new work, the scientists were surprised to see so many snails followed the slimy trails laid by others. Dr Hodgson says it is all about conserving energy.

"We know that snails use about 40% of their energy budget producing slime.

"Given a chance, a snail will prefer to follow a trail that has been laid by another, it is a form of cheating like slipstreaming," he said.

As to what pet owners should do, the scientists suggested they should regularly check the nooks and crannies in their gardens for snails and try to reduce exposure to the species.

"I wouldn't be too happy suggesting that there should be a snail apocalypse and everyone should get rid of them," said Dr Hodgson.

"I think awareness is a better idea, people need to understand the wildlife in their gardens and that no organism is totally harmless."[You must be registered and logged in to see this image.]
The lungworm parasite can be fatal in dogs and researchers say it is spreading across the UK

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For anyone who has seen the item on the BBC about dogs getting lungworm from snails.

They seem to have overlooked the fact that slugs carry them as well. And as for this being news... ask any hedgehog rescue and they will show you the slides from the faecal samples we've been taking for years. News? Yawn.

The following is a shot of a sample containing lungworm larvae and roundworm eggs. In the autumn pretty much every hog that comes in has these darn things and they can kill.