Effect of different feeding diets on the haemolymph of the newly emerged honeybee workers Apis mellifera L.

Five diets were compared for measuring their effects on the differential haemocytes types of the newly emerged worker bees, and also on their haemolymph proteins, lipids and glucose content. As blood haemocytes cell play a role in defending honeybees against parasites and pathogens. Five groups of newly emerged worker bees were fed with one of the following diets in patty form with sugar: faba bean (Vicia faba) pollen, maize (Zea mays) pollen, date palm (Phoenix dactylifera) pollen, Egyptian clover (Trifolium alexandrinum) pollen and soya bean (Glycine max) flour (as pollen supplement). Differential haemocyte counts (DHC) were evaluated in smears of their haemolymph. The types of the haemocytes (prohaemocytes, plasmatocytes, oenocytoids, granulocytes, coagulocytes and binucleated cells) were recorded. The most abundant type was plasmtoycte cells (over 90%) followed by granulocyte cells and coagulocyte cells. These blood cells perform phagocytosis and encapsulation of foreign bodies in the honeybee body cavity. Feeding honeybees with these different diets caused significant differences between the haemocyte cells. The highest number of plasmatocyte cells recorded in bees which fed on maize pollen, while the lowest was found in bees fed on bean pollen. The highest protein content was found in the haemolymph of bees fed on date palm and the lowest was found in bees fed on bean pollen and the difference was non-significant. The difference in lipids content was non-significant in worker bees fed on these different diets. There was a significant difference in glucose content between bees fed on maize pollen and date palm pollen.