[Antigens of the blood group I and i on the surfacc of chicken erythrocytes].

I and i blood group antigens have been looked for an Chick erythrocytes using purified and 125 I anti-I, anti-i and anti-I i antibodies. No I antigen is found but i determinants are detected on embryo and adult Chick erythrocytes. This i reactivity is different from the embryonic and adult antigens respectively specific for embryo and adult Chick erythrocytes. Treatment of the erythrocytes with nuraminidase increases the i reactivity. Incubation with papain reduces the fixation of anti-i antibodies suggesting that the i determinant of Chick erythrocyte could be linked to glycopeptide chains.