When we give blood or need a blood transfusion, we have to think about our blood types — or blood groups as scientists refer to them.
But how much do animals think about their blood types? Probably never, given what we know about animals. But we humans do think about our animals, because sometimes animals receive blood transfusions too, and we want to make sure the blood we’re giving doesn’t cause a blood incompatibility reaction. That’s a negative reaction, causing the recipient’s immune system to attack foreign blood, producing antibodies (抗体) against the red blood cell proteins, or antigens (抗原), in the donated blood. Although all animals have blood groups, every species has a different system, and we know the most about the systems of domesticated mammals.
Dogs, for their part, have more than 8 different antigens that can attach to their red blood cells. Most of them are labeled Dog Erythrocyte Antigen (DEA 1.1, 1.2, 3, 4, 5, 6 and 7). Often, individuals within a specific breed of dogs will have the same blood type — for instance,60 percent of greyhounds fall into the DEA 1.1 negative (the universal dog donor) blood group. But new dog blood groups are still being detected — the recently discovered Dal blood group, for example, is only found in Dalmatians.
Cats, on the other hand, have only 2 possible antigens — A and B, although they aren’t the same A and B antigens found in human blood. There is no universal donor or recipient feline blood groups, but the vast majority (around 90 percent) of domestic cats have type A blood, while more special purebreds often type B. AB is also possible, but very rare.
Like dogs, horses’ blood groups are loosely organized along breed lines, but there are 30 different groups. That represents combinations of 8 different antigens (A, C, D, K, P, Q and U are internationally recognized, while T is still being researched). Cows are tricky because there are 11 major blood groups (A, B, C, F, J, L, M, R, S, T and Z), but the B group includes over 60 different antigens, making blood matches for transfusions tough.
12. Why can’t an unmatched blood transfusion be given?
A.It causes a positive reaction. | B.It produces antibodies in the blood. |
C.It causes genes to change. | D.It produces the red cell proteins. |
13. What can we learn about the blood types of dogs?
A.Dogs have the same blood types as horses. |
B.Dal blood group is very common. |
C.The DEA 1.1 negative blood group is common. |
D.The blood types of dogs are very rare. |
14. What’s the writer’s attitude to the blood transfusion of animals?
A.Scientific. | B.Opposed. |
C.Changeable. | D.Negative. |
15. What is the best title for the text?
A.A Research on Animal’s Blood Types. | B.Animal’s Safe Blood Transfusion. |
C.Animal’s Blood Types and Transfusion. | D.Domesticated Mammals. |