Studies on haemocyanin and haemolymph protein levels of Penaeus japonicus based on sex, size and moulting cycle

Abstract

1. Mean (± SE) haemolymph protein level was 64.78 ± 4.06 and 62.24 ± 4.13 mg/ml, while mean haemocyanin level was 0.72 ± 0.05 mol/l for male (12.45 ± 0.60 g, N = 27) and female (12.41 ± 0.68 g, N = 21) Penaeus japonicus, with no significant difference between the sexes. 2. Protein and haemocyanin in the haemolymph of shrimp significantly increased (P < 0.05) with increased weight in the range of 7.56–21.22 g (N = 70). 3. Among the moulting cycles tested, the shrimp had the highest mean (± SE) protein (74.90 ± 4.61 mg/ml) and haemocyanin (0.73 ± 0.04 mol/l) at the D0 stage, and had the lowest protein (41.37 ± 3.11 mg/ml) and haemocyanin (0.42 ± 0.02 mol/l) at the B stage. 4. Haemocyanin accounts for 64% (C stage) to 72% (D3 stage) of protein in the haem