Ontogenetic expression of larval and adult hemoglobin phenotypes in the intergeneric salmonid hybrids.

Ontogeny of the hemoglobins of Honmasu (Oncorhynchus rhodurus, HXH),brook trout (Salvelinus fontinalis, BXB) and their reciprocal hybrids (HXB and BXH) was examined electrophoretically as well as spectrophotometrically. All of these fish have electrophoretically distinct larval and adult type hemoglobins and the transition from one type to the other occurred early during post-hatching development. In the case of larval hemoglobins, the electrophoretic pattern of a hybrid, BXH, resembled that of the maternal parent, brook trout (BXB), while the hemoglobin of the reciprocal hybrid, HXB, differed markedly from that of the maternal parent, Honmasu (HXH), in that it possesses a diffuse pattern. Spectrophotometric examinations indicated that this was mostly methemoglobin. Adult type hemoglobins at more advanced stages of both hybrids were electrophoretically resolved into the parental hemoglobins. However, no "hybrid" hemoglobins were detected. Because there was abnormal hemoglobin formation in the larval erythrocytes (erythrocytes L) of the HXB hybrid, and then normal hemoglobin synthesis in the adult erythrocytes (erythrocytes A) of the same fish at later developmental stages, it appears that the paternal effects upon the hemoglobin differed in these two erythroid cell lines of the developing trout.