A Contribution to the Problem of Blood Groups in Ducks
In connection with the experiments of Hašek and coworkers on the induction of immunological tolerance to homologous erythrocytes in adult ducks, we obtained specific antibodies against red cell antigens. We used Peking ducks in these experiments. 30 exsanguination transfusions in adult ducks were carried out. In six (i.e. 20%) tolerance was elicited, in 24 (i. e. 80%) antibody formation took place. Among these, 19 sera (i. e. 80%) had a titre lower than 32, mostly 2–8; these sera reacted weakly and gave badly reproducible results, their specificity was not yet studied in detail. Only 5 sera (i.e. 20%) had an antibody titre higher than 64, gave strong reactions and excellently reproducible results. Specificity of these sera was examined in detail and the results showed that they all reacted in the same way. We denoted them anti-A, and the ducks, according to the reaction to these sera, A + and A−.