Haemocyte changes in honeybee (Apis mellifera L) artificially infected by Pseudomonas aeruginosaK. Papadopoulou-Karabelaa, N. Iliadisb and V. Liakosb
a Ministry of Agriculture, Veterinary Station, 63100 Polygyros, Halkidiki, Greece
b Faculty of Veterinary Medicine, Aristotelian University of Thessaloniki, 54006 Thessaloniki, Greece
Abstract - The changes in haemocytes of honeybees artificially infected with Pseudomonas aeruginosa ATCC 27014 (P apiseptica), the bacterium known to cause septicaemia, were studied. It was found that the time of clinical manifestation did not significantly affect total and differential haemocyte counts. In the haemolymph of infected bees which showed no clinical symptoms the percentage of oval plasmatocytes was higher (P ≤ 0.05), while the percentage of round plasmatocytes was lower (P ≤ 0.05) 10 h after infection. The above changes were also observed in diseased bees independently of the time of clinical manifestation. There was no difference (P > 0.05) in the percentage of granulocytes and mitotically dividing haemocytes between diseased and control bees. The percentage of degenerated and/or dead haemocytes was higher in the haemolymph of diseased bees.
Key words: Pseudomonas aeruginosa / haemocyte count / experimental infection