Various species require different
levels of testing to ensure a compatible match. Cats have 3 blood
types, cattle have 11, dogs have a dozen, pigs 16 and horses have
34.
Blood is species specific dogs can receive only dog blood and cats
can receive only cat blood. In addition, dogs and cats have blood
types just as humans have blood types. Cats have A, B, and AB
groups with specific factors within these groups that further
differentiate them. Dogs have eleven different blood groups; the
most important one is the A1/A2 system. Dogs that are A negative
are considered universal donors. In dogs, DEA 1.1 (Dog
Erythrocyte Antigen) has been found to be the part of the blood
type most likely to cause a transfusion reaction. The blood type in
dogs is either DEA 1.1 positive or DEA 1.1 negative. There are
however, other parts to the canine blood type, including DEA 1.2,
DEA 3, DEA 4, DEA 5 and DEA 7. In order to determine the full blood
type, blood needs to be submitted to a special laboratory. Cats do
not have a universal donor; therefore, it is especially important
that donor and recipient are
cross matched.
Multiple transfusions can also be a
problem. Even though the donor and recipient may be compatible
originally, the recipient's immune system may build up a
sensitivity to a specific donor. Therefore, every time you
transfuse, you need to cross match to make sure that your donor and
recipient are compatible.
There are two types of cross
matching tests, major and minor cross matching. Major cross
matches, red cells from the donor are mixed with serum from the
recipient. We observe to see if there is a reaction, the recipient
may attack donor cells and not accept them. If you have a major
cross match incompatibility, unless you are desperate, you
shouldn't do a transfusion. In a minor cross match, the recipient's
red cells are compared with the donor's serum. Usually, in minor
incompatibilities, parts of the donor's blood can be given to the
recipient but not the blood in its entirety.
The different blood components red
cells, plasma, and platelets can be separated if need be. Red blood
cells are given to a patient that may be anemic due to trauma or
due to a treatable disease. Plasma is used to build up blood volume
in situations when the animal is not making enough or is losing too
much protein. Platelet rich plasma is for those patients whose
platelets are depleted or dysfunctional.
As with human blood donors, animal
donors are tested to make sure blood values are high enough and no
infectious disease is present before blood is drawn. Donors must
meet weight requirements 10 pounds for cats and 50 pounds for dogs.
Fluid is replaced after blood is drawn, and the body compensates by
producing new red blood cells. Also similar to human donors, there
must be a waiting period of at least two months before blood is
collected again.
