Neuroendocrine Role of Eyestalks in Respiratory Regulation of Swimming Crab Portunus pelagicus (Lineaus, 1857)
ABSTRACT Abstract: Purpose: The effects of eyestalk ablation and eyestalk extract injection on oxygen consumption and hemocytes count of Portunus pelagicus were studied over the 30 animals. Oxygen consumption in destalked animals was higher than in normal ones, whereas oxygen consumed by eyestalk extract injected animals was lesser than normal ones. Results: The oxygen consumption in both the sexe� s increased significantly after eyestalk ablation and decreased after eyestalk extract injection vigorously. Statistical analysis of the results showed significant differences in both sexes between stalked and destalked animals as well as stalked and eyestalk extract inject ones (p<0.05). The total hemocyte count was found to be high in injected females (1.493x107 cells mL-1) while as in males, the total hemocyte count was found to be high in normal crabs (1.073x107 cells mL-1). Conclusion: The mean number of circulating hemocytes in female P. pelagicus was found to increase significantly due to eyestalk injection. Thus clears that the ablation decreases the total hemocytes count in these crabs.