Bovine Fetal Hemoglobin. I. Postnatal Persistence and Relation to Adult Hemoglobins

The postnatal persistence of bovine fetal Hemoglobin (F) and its relation to the adult Hemoglobins A and B were investigated by electrophoretic methods. At birth, F made up 41 to 100% of the total hemoglobin of 23 calves. The amount of F diminished rapidly and was replaced entirely by Hemoglobin A in 14 bull calves and four heifer calves at the average ages of 65 and 97 days, respectively. The disappearance of Hemoglobin F from the blood of five calves (Guernseys, Jerseys, Brown Swiss) was obscured by the simultaneous appearance of Hemoglobin B, which has the same eleetrophoretic mobility as F under the conditions used. Comparisons of electrophoretic mobilities in the pH range 6.5-9.0 showed that Hemoglobin A has a greater net positive charge than B and F throughout, but that the net positive charge of Hemoglobin B is appreciably greater than that of F only below pH 7.4. Above this pH, B and F migrate on paper electrophoretie strips at essentially the same rate.