I found this on another site .
Dogs do not have the same Blood Typing Groups as Humans...ABO. Instead they have a series of possible combinations based on DEA (Dog Erythrocyte Antigen) from DEA 1.1, 1.2, 4, 7 and others. The most important one to know is DEA 1.1+...this would be similiar to O+ in humans as in Univeral Recipient (they can accept any blood type without complications). The other extreme would be DEA 4...this would be similiar to AB- in humans (very rare) as in Univeral Donors. All other DEAs, excluding DEA 1.1+, are universal donors when it comes to dogs.
One good thing about dogs is they get one "free pass" when it comes to a blood transfusion. They do not carry antigens naturally that react to different types of blood, so in an emergency any dogs blood will suffice. The problem is the second time a transfusion is needed. If DEA 1.1+ was used in a dog that was not DEA 1.1+, the dog now HAS developed allo antibodies and a new transfusion with DEA 1.1+ blood could be fatal. The other problem is when a female that has had a DEA 1.1+ transfusion is feeding her pups, it can cause problems. Hemolytic Transfusion Reaction can be fatal.
For people that have multiple "pit bulls" the news is pretty good. Most all "pit bulls" as with most Greyhounds, Boxers, Irish Wolfhounds, German Shepherds and Dobermans are DEA 1.1 negative so they are univeral donors between themselves.
Your Vet should be able to test for your dog's bloodtype with an ID GEL TEST (takes about 20 minutes) or do the Alreadia Quick Test (takes about 2 minutes) for the DEA 1.1+ blood type. Either way, I think it is a good thing to know about your dog ahead of time. All blood should be screened for blood transmitted diseases Babesiosis and Leishmaniasis.
_________________He who hangs with fools becomes one!!!