Neuroendocrine regulation and pesticidal impact on freshwater crab, Barytelphusa guerini (H. Milne Edwards).

The extensive use of pesticides to control agricultural pests poses a serious threat to many non-target organisms of the aquatic environment such as the freshwater crab, B. guerini. The deleterious influence of the pesticide causes physiological, biochemical, histological and such other disorders in the animal exposed. In the present study impact of an organophosphate pesticide, monocrotophos and neuroendocrine regulation on the biochemical contents of hepatopancreas of B. guerini has been studied. Experimental studies revealed that glycogen and protein content decreased in normal crabs when exposed to sub lethal concentrations of monocrotophos, while lipid content was increased. In the ablated and pesticide exposed crabs glycogen, protein and lipid contents decreased. In case of ablated and exposed crabs when injected with eyestalk extract, glycogen and protein contents declined, whereas lipid content hiked. It was observed that glycogen, protein and lipid contents in eyestalk extract injected crabs were similar to those of normal exposed crabs. This indicates the vital role of eyestalk in the regulation of biochemical contents. Histological studies of the hepatopancreas indicate structural changes such as large number of vacuolated cells and phagocytes when exposed to the pesticide.