Blood groups in domestic dogs
Blood groups , defined by different antigens on the surface of the red blood cells , occur in all mammals . In dogs , the blood group is controlled by five different, mutually independent loci , the clinical importance of which in transfusion medicine is different and whose allele frequencies can vary greatly between the individual races . In total, there are over 30 different possible blood groups.
Clinically, the first transfusion in dogs is usually unproblematic. In the case of subsequent transfusions or in dogs with an unknown history, however, it is essential to ensure the compatibility of the blood groups in order to avoid potentially life-threatening transfusion reactions .
nomenclature
In the past six blood groups were differentiated in the literature and designated with letters, but this is outdated today. The current system assigns each series a DEA number to, where the abbreviation "DEA" for D og E rythrocyte A ntigene stands. Each DEA series corresponds genetically to a locus . Groups relevant for transfusions are given in the following table:
| old name | DEA number | Frequency (%) | Natural antibodies ? | Transfusion effect |
|---|---|---|---|---|
| A1 | 1.1 | 42 | No | Acute hemolysis |
| A2 | 1.2 | 20th | No | Acute hemolysis |
| B. | 3.0 | 6th | Yes | Late reaction, not hemolytic |
| C. | 4.0 | 98 | Yes | None |
| D. | 5.0 | 23 | Yes | Late reaction, not hemolytic |
| Tr | 7.0 | 45 | Yes | Late reaction, not hemolytic |
DEA 1.0 series
The DEA 1.0 series knows four alleles (1.1, 1.2, 1.3 and null), which lead to four possible phenotypes with the same name. There is a linear dominance between these alleles ; 1.1 is the most dominant, zero the most recessive allele. A dog with phenotype 1.1 can therefore have genotypes 1.1 / 1.1, 1.1 / 1.2, 1.1 / 1.3 or 1.1 / zero.
There are no naturally occurring antibodies against the DEA 1.0 series alleles. DEA 1.1-negative dogs that have received a DEA 1.1-positive transfusion are sensitized and can react with haemolysis if DEA 1.1-positive blood is transfused again . DEA 1.1-negative bitches can also trigger maternally induced haemolysis in their DEA 1.1-positive puppies after sensitization (analogous to the Rh factor in humans; type II hypersensitivity reaction ). This mechanism seems to be clinically relevant only in bitches who have been sensitized by a blood transfusion.
DEA 3.0 series
The DEA 3.0 series contains alleles 3.0 and zero, with 3.0 being dominant over zero. Naturally occurring antibodies exist; If a zero / zero dog receives phenotype 3.0 blood, the erythrocytes obtained are eliminated within 3-5 days.
The 3.0 phenotype is rare, but is more common in greyhounds and Japanese dog breeds.
DEA 4.0 series
The DEA 4.0 series contains the 4.0 and zero alleles, with 4.0 being dominant over zero. In the (very rare) zero / zero dogs, naturally occurring antibodies against blood of phenotype 4.0 exist, but this does not seem to be clinically relevant. DEA 4.0 positive dogs that are negative for all other series are considered universal donors.
DEA 5.0 series
The DEA 5.0 series contains the 5.0 and zero alleles, with 5.0 being dominant over zero. DEA 5.0 positive dogs are rather rare; natural antibodies are found in negative dogs. If a zero / zero dog receives blood of phenotype 5.0, the erythrocytes obtained are eliminated within 3–5 days.
DEA 7.0 series
The DEA 7.0 series contains alleles 7.0 and zero, with 7.0 being dominant over zero. There may also be an additional allele. DEA 7.0 is not a real surface antigen of the red cells, but is produced in the tissue and absorbed by the erythrocytes - therefore the 7.0 status does not change even after a bone marrow transplant .
The majority of Null / Null dogs have naturally occurring antibodies to the 7.0 phenotype. Such dogs eliminate 7.0 erythrocytes obtained after a few days, the elimination being slowed compared with the 3.0 and 5.0 series.
literature
- Romesh K. Juneja, John A. Gerlach, Anne S. Hale: Biochemical Genetics and Blood Groups of the Dog. In: Anatoly Ruvinsky, Jeff Sampson (Eds.): The Genetics of the Dog. CABI Publishing, Wallingford et al. 2001, ISBN 0-85199-520-9 , pp. 117-137.
