Significance of periodic fluctuations in the haemolymph proteins and their catabolic products during starvation and repeated injury in Scylla serrata (Forskal)

Abstract

AbstractThe fate of haemolymph proteins during the course of prolonged starvation was investigated. Two different experimental protocols were set up. In experiment 1, sampling of the haemolymph was done in a group of six crabs at 3‐day intervals up to 33 days (group 1). In experiment 2, separate groups of crabs were sampled at 3‐day intervals up to 33 days (group 2).There is no change in body weight. The haemolymph volume and water increase significantly indicating hydration of haemolymph. The haemolymph protein concentration and quantity decline significantly in both groups during the course of prolonged starvation. Concomitantly, the haemolymph free amino acids concentration and quantity increase in both the groups, indicating degradation of protein during the course of starvation.That degradation of protein cannot occur continuously but rather takes place on specific days in both groups is indicated by the increase in the products of protein catabolism—namely, free amino acids and ammonia. The results also provide evidence for the mobilization of proteins from storage sites. Nonprotein dry weight increases markedly during the course of starvation, the significance of which is discussed.