Nuclear lobe index in avian eosinophilia

The nuclear lobe index was calculated for eosinophils from adult fowl, ducks and quail with spontaneous or experimentally induced eosinophilia. Appropriate control birds were also examined. The nuclear lobe index in normal fowl was 1.95 compared with 1.91 in birds with eosinophilia. Although these results (in the fowl) are almost identical, further analysis revealed a distinct 'shift to the right' in those birds with counts greater than 20 per cent eosinophils (P less than 0.01). The normal nuclear lobe index in ducks was 2.68 compared with 2.60 in those with eosinophilia and thus no 'shift' was recognised. The quail, on the other hand, demonstrated a slight 'shift to the left' in which the normal nuclear lobe index was 2.46 compared with 2.20 lobes per cell in eosinophilic quail.