In the UK there's a company called PetBloodBank that has started blood donations in dogs and storing it. We signed up for it when we were at Crufts and now we're taking our greyhound for his first one on Saturday!
Its excellent as your dog gets a free health check and full blood work up on a yearly basis and then he donates the blood and afterwards gets treats, a goody bag and a bandana! Best of all at least 2 dogs lives will hopefully be saved!
here's the site for UK people:
Pet Blood Bank UK -
Dogs have to be between 1 and 8, over 25 kgs and generally fit and healthy.