Some of the dogs have been tortured – burned with cigarettes and acid – some dumped to die in tunnels, hung in trees or released on busy motorways. 

Others have been left with broken bones to starve to death. 

In at least one case, a rope had become so deeply encrusted in the neck of a greyhound it had to be surgically removed by a vet while dozens of others have had gaping, open wounds – the results of abuse - by the time they are found by volunteers across Spain. 

Many have been found homes with families in Britain and across Europe - all treated by vets in Spain at shelters supported by the group. 

Disturbing new video recently obtained by GIN and filmed undercover in the Spanish countryside shows locally-bred hunting greyhounds, known as galgos in Spain, being held from the back of a pick-up on leashes and made to keep up with the vehicle as part of their training for blood-sport competition during the four-month long hare coursing season. 

When the video of the five greyhounds being ‘dragged’ from behind the truck was shown by GIN at the Royal Society of Medicine in London, there was outrage. 

‘They are awful pictures,’ said Martin Humphery, of GIN, ‘It is very clear that they are suffering greatly. 

‘We hope that it will finally help open eyes to the kind of abuse that is going on. It is very disturbing but sadly typical of the kind of things that is going on with these poor galgos. 

‘There is supreme neglect and cruelty on a large scale. 

'We have had cases of dogs being tied to rocks and left to starve to death, others with cigarette burns and some just thrown over fences and abandoned with broken legs.’ 

GIN works with a network of shelters across Spain where the primary rescue and treatments are carried out. 

It funds vets, treatment, shelters and care – and assists in finding homes with families of greyhound lovers in Britain, Italy, Belgium and France. 

Among those supporting the organisation, which spends around £250,000 a year on saving the dogs – funding comes mainly from donations and two shops on the South Coast run by the charity - is comedian Ricky Gervais, who has highlighted the plight and mistreatment of greyhounds around the world on Twitter. 

Oscar winning actress Dame Judi Dench, author Jilly Cooper and actor Peter Egan, a star of Downton Abbey – the owner of six rescue dogs - are among GIN’s heavy-weight patrons. 

Last month a shipment of eight dogs arrived at GIN’s kennels at Wraysbury, near Windsor, while they await adoption with their details posted on the organisation’s website.

In Spain, they had been treated at shelters, sterilised, micro chipped and have been tested and found clear of Mediterranean diseases before they come to the UK.

(dailymail.co.uk)