An online animal blood register has been set up by a driving instructor after her golden retriever fell seriously ill with a blood disorder.
The database stores information on potential canine blood donors
Diana Cruttwell, 56, from Peterborough, joined forces with her vet Dr Clive Elwood to create the site when her dog had to have several blood transfusions.
The free database brings together potential donors with vets, who then match and check the blood.
The service is thought to be the first of its kind in the UK.
It is the canine equivalent to the human blood bank system, but stores information on potential donors, rather than actual blood.
Mrs Cruttwell's own dog, Abi, had to have three transfusions, but her vet was able to use blood from three of her other dogs to treat Abi's condition.
However, the experience highlighted how difficult it was for dog owners to find suitable donors in a medical crisis.
Mrs Cruttwell, a former police officer who now runs her own driving school, said she hoped the database would save lives.
She said: "I think it's important that people know their animals can be donors."
Mr Elwood, of Davies Veterinary Specialists in Higham Gobion, Bedfordshire, said: "Every year very many dogs suffer from conditions requiring blood transfusions.
"By making it quick and easy for vets to locate a suitable blood donor, the site should literally save the lives of hundreds of sick animals."
A RSPCA spokesman said: "The RSPCA welcomes the website as a useful tool which can help save the lives of dogs.
"Blood must be taken by vets from dogs of suitable age and health."