A SURVEY OF BLOOD GROUPS IN SEVERAL SPECIES 
OF LARGE ANIMALS USED IN MEDICAL RESEARCH 
Clyde J. Stormont* 
The first systematic studies of blood groups in large 
species of domestic animals were begun on cattle in the 
late 1930's in the laboratory of M. R. Irwin at the Uni- 
versity of Wisconsin. The appropriate serological 
approach, which had long been overlooked, was the prep- 
aration of blood typing reagents from isoimmune anti- 
sera and the use of hemolytic tests rather than agglutina- 
tion tests, the latter being clearly contraindicated for 
the red cells of such species as cattle. This approach 
paid off. Already by 1941 some 30 isoantigenic deter- 
minants on cattle red cells were known."'** That num- 
ber was somewhat unprecedented when we consider 
that only about eight markers (Ai As, M, N, P, Rho 
and rh') were then recognized on human red cells. 
In the course of exploring blood groups in domestic 
animals numerous firsts have come to light. Of particu- 
lar significance among those firsts was the discovery, by 
R. D. Owen, of erythrocyte mosaicism or blood group 
chimerism in dizygotic cattle twins and higher zygotic 
multiples.*" His observations stimulated much of 
the work on immunological tolerance and are basic to 
theories on that subject.' I, therefore, take this oppor- 
tunity to set forth a number of additional firsts which 
have influenced our thinking about blood groups. 
INTRODUCTION 
Most of the investigations of animal blood 
groups are contemporary, that is, from about 
1940 onwards. The same is true of human blood 
groups with the exception of the earlier studies 
on the ABO groups, M-N types and P types. 
This is not to say that there was no work or lit- 
tle work on animal blood groups prior to 1940. 
On the contrary, there were many studies but, 
for the most part, they were transient surveys 
concerned with a search for naturally occurring 
isoagglutinins that might detect in animals a 
system of blood groups akin to the ABO groups 
of man. Those earlier studies have been con- 
cisely reviewed by Wiener.* 
Today there is an extensive literature about 
blood groups in cattle, horses, pigs and sheep 
but much less so for dogs. There are several 
* Serology Laboratory, Department of Veterinary Microbiology, 
University of California, Davis, California. 
reasons for the less extensive literature on dog 
blood groups, and I would like to touch upon 
those reasons at this point. The lack of litera- 
ture on dog blood groups is not because of a 
lack of interest in dog blood groups. On the con- 
trary, there have been numerous attempts to 
produce antibodies that might detect individual 
differences in the antigenic structure of dog 
erythrocytes, as evidenced, for example, by the 
efforts of L. E. Young and colleagues. (See re- 
view by Swisher et al.^) In spite of the efforts, 
only 8 blood factors have been identified to date. 
Three (C, F and G) are of such high frequency 
(incidence greater than 0.98) that they are of 
little interest in routine typing, and apparently 
none of the laboratories presently involved in 
dog blood typing has available more than 4 or 5 
different typing fluids. 
Another problem left unmentioned in reports 
on blood groups in dogs is that dog red cells are 
difficult to work with because of the existence 
on those cells of an autolytic factor which ren- 
ders them vulnerable to hemolysis when washed 
and suspended in virtually any neutral serum. 
This autolytic factor, which seems to be an at- 
tribute of the red cells of all dogs, is much like 
that encountered by us in blood typing studies 
on the red cells of certain Arabian horses.'^ 
One might ask, what kind of information 
about animal blood groups would those who use 
the larger species of domestic animals for phys- 
iological studies, experimental surgery and 
organ transplantation be particularly interested 
in ? If the answer relates mainly to transfusion 
reactions and the possibility of using the anti- 
genic markers as indicators of histocompati- 
bility, I could complete my assignment here in a 
few paragraphs. 
Irrespective of incompatibilities in blood 
types, reactions on initial transfusions are 
rarely seen in cattle, dogs, pigs and sheep. 
505 
