Sequential morphological changes in chicken erythrocytes after in vivo and in vitro exposure to phenylhydrazine-hydrochloride.

In acute haemolytic anaemia of chickens, induced with the oxidant chemical phenylhydrazine-hydrochloride, maximum degenerative changes in the in vivo exposed erythrocytes occurred on day 3 after injection. Microspherocytic transformation, dumb-bell shaped red blood cells and foamy squashed nuclei predominated. Heinz body formation was the cytoplasmic hallmark of the haemolytic anaemia. Marked reticulocytosis on day 5 indicated spontaneous regeneration. In vitro exposure to the chemical agent evoked similar morphological aberrations/Heinz bodies, microspherocytic transformation and nuclear degeneration. These were induced much earlier, presumably because of the absence of a protective internal milieu. Nevertheless, a basic similarity in morphology was evident. The in vitro test system might be suitable for screening oxidant chemicals and drugs.