4.Endocrine involvement in osmoregulation in a Freshwater Crab Barytelphusa guerini
Vaishali Gangotri and Madhav Gangotri
The effect of eyestalk ablation on osmotic and ionic regulation, the total ATP-ase and Na+ / K+ATP-ase activity of the freshwater crab, Barytelphusa guerini (H. Milne Edwards) (Decapoda, Potamidea) investigated in a period of 30 days. The survival rates of normal and eyestalk ablated animals were 75% and 50% after 30 days of treatment, respectively. Bilateral eyestalk extirpation showed the increase in weight of the animal after 30 days. Hence, suggests the retention of water in tissues after eyestalk ablation. Eyestalk ablation resulted in a decrease in the haemolymph sodium concentration and an increase in the potassium and calcium concentration of the crabs. The osmolarity of haemolymph and total protein concentration of eyestalk ablated animal were demonstrated to be higher than those of the normal intact animal. The bilaterally eyestalk ablated crabs had higher total ATP-ase and Na+ / K+ATP-ase activities in the gills than those of normal intact animals. It is concluded that the eyestalk ablation of crabs causes significant changes in the osmotic and ionic regulation and also affects the total ATP-ase and Na+ / K+ATP-ase activity of the gills.