Differences in Frequency of Cellular Antigens in Two Breeds of Dairy Cattle

Abstract

Frequencies of 30 cellular antigens in a sample of 569 Guernseys were compared with those of 513 Holstein-Friesian cattle. Not all animals were tested for all antigens. Eighteen of the antigens were found to be significantly more frequent in Guernseys; seven were not significantly different in frequency in the two breeds; while five were significantly more frequent in Holsteins. There was a marked tendency for the relative position of an antigen's percentage-frequency on the scale in one breed to agree with its relative position in the other. The profile of percentage-frequencies in each breed was similar to that expected from the characteristics of the technique of detection of antigens. No single antigen by itself distinguishes these two breeds. Rather, the breed differences in blood type are the result of quantitative differences in the frequencies of most of the antigens. Although the computation of simple gene frequencies cannot be accomplished until the genetic associations between antigens are better established, there is little doubt that the breed differences in antigen frequency are the result of contrasting gene frequencies among genes common to the two breeds. Each breed appears to be potentially capable under selection of producing individuals identical in blood type with members of the other breed. Copyright © . .