Abstract

CELLULAR IMMUNITY STUDIES OF FRESH MUD CRAB SCYLLA SERRATA FORSSKAL, 1775

C.H. Saritha Subhashini and P. Nagarajarao*

ABSTRACT

Mud crabs that dwell constantly exposed to biotic stress throughout the year. Therefore, it is interesting to know how crabs regulate their biotic stress physiology to counteract the bacterial induction. To understand the relationship between bacterial induction and biotic stress physiology two experiments were designed. The present study is a comprehensive attempt to examine the relationship between bacterial induction of biotic stress physiology of mud crabs (S. serrata). In the first experiment, various biochemical components physiology of mud crabs collected in the fields were studied at different seasons. In the second experiment, parameters were investigated in animals that were first acclimatized in the laboratory and then exposed to different bacteria for the biochemical changes. In both the experiments, the objective was achieved by quantifying selected biochemical parameters related to biotic stress and antioxidant defences in different tissues of mud crabs such as muscle, gills and hepatopancreas. Hemocyte classification is based on the presence and size of cytoplasmic granules into 3 types: hyaline, semi-granular and granular hemocytes. Following this criterion, three types of circulating haemocytes were recognised in the crab, Syclla serreta, hyalinocytes, Small granulocytes and large granulocytes.

Keywords: Biotic Stress, Hemocytes, Granulocytes, Syclla serreta.