Dog owners are being encouraged to sign their pets up to help save the lives of others - by becoming blood donors.

Paragon Veterinary Group is aiming to build up a list of canines it could call on in the event of another dog needing an emergency blood transfusion.

Veterinary surgeon Graham Lewis explained that the need to give a dog a blood transfusion is something that only happens once or twice a year. And, although supplies are available from the Pet Blood Bank, it can take time to arrive and only has a 30-day shelf life.

He said the time it takes to get the blood could be the difference between life and death.

"It's like in humans. When we get to the stage we need to do a transfusion, it's often fairly urgent, there and then needing done," Mr Lewis said.

Paragon launched a similar campaign about three or four years ago and managed to drum up support for a more local supply.

Willing owners with suitable dogs left their contact details, but as animals have died or moved away over the years they have just three names left on the emergency list.

Mr Lewis explained that although dogs have different blood types the first transfusion can be safely done with any blood type.

"If it was for subsequent ones after that then you do [need the same blood type]," he said.

"It's quite rare. I have only had to do it in a couple of cases and those are cases that we've been able to keep blood in.

"The problem with blood is, as with human blood, it doesn't last very long."

He is encouraging anyone who owns a dog to consider how it could help their pet if it was in needed.

"It is very similar to what we have in a human situation. If you were in that situation yourself you would want somebody to be giving blood," he said.

"It's the same with dogs. In a lot of these cases the reason behind it is not anything the owner has done.

"The dog has a disease or its eaten something like rat poison and it needs the treatment.

"Taking the transfusion, it doesn't make the other dog ill. It certainly saves lives."

Paragon has practices at Dalston, Carlisle and Newbiggin near Penrith.

Pet Blood Bank UK, was launched in 2007 and provides a canine blood bank service for all veterinary practitioners across the UK.

A spokeswoman for the Pet Blood Bank UK said: "Blood is available 24/7 by same day courier from Loughborough or via PBB's sharing scheme."

The nearest stockist to Paragon is 40 to 50 miles away.

Call 01228 710208 for more information.