Inheritance of R-o-i Blood Groups and Alkaline Phosphatase Polymorphism in Sheep.

RENDEL and STORMONT (1964) found that in sheep sera subjected to starch-gel electrophoresis the zone of phosphatase activity which they designated B is highly correlated with the presence of soluble blood-group substance 0 in adult females. Since the presence of 0 substance is recessive to the presence of R substance ( STORMONT 1951 ; RENDEL, NEIMANN-SBRENSEN and IRWIN 1954), they inferred that the presence of the B zone was also a recessive trait. RENDEL, AALUND, FREEDLAND and MBLLER (1964), in tests of yearling sheep, confirmed the association between B phosphatase activity and 0 substance. However, tests of sera of lambs 2% to 4 months of age revealed a less marked association; there was some B phosphatase in the serum of most lambs regardless of their R-0 blood groups, although the mean B-zone score in lambs of group 0 was significantly greater than in lambs of group R. The data presented in this report were collected as part of a survey of serum alkaline phosphatase types of sheep and pigs. Tests of sera of sheep of groups R, 0 and i provide additional data on the association between the B phosphatase zone and group 0 in sheep and the absence of the B zone in R and i sheep. The A-0 blood-group system in pigs (RASMUSEN 1964) is related to the R-0 system in sheep, but no polymorphism of alkaline phosphatase types in pigs related to A-0 blood groups was found when sera from pigs were tested using the same techniques as for sheep. Sera from Duroc and Yopkshire pigs all had a phosphatase band comparable to the A band of sheep, and all sera tested lacked a band comparable to the B band, regardless of whether they were of group A, 0 or "-". Therefore only the data for sheep are reported here.