After 32 days of post feeding, a significant increase in total haemocyte count (THC), different haemocyte count (DHC),respiratory bursts (RBs), superoxide dismutase (SOD) activity, glutathione peroxidase (GPx) activity,phenoloxidase (PO) activity and transglutaminase (TG) activity, and meanwhile, a decreased haemolymph coagulation time was observed. Furthermore, phagocytic activity and clearance efficiency of prawns against Lactococcus garvieae infection were significantly increased