Study on the morphology and classification of haemocytes in adult Neomysis japonica and the immune enzyme activities at different developmental stages in Neomysis japonica

In order to classify the haemocytes of adult Neomysis japonica, light and electron microscopical studies were carried out. According to the presence or the absence of cytoplasmic granules, nucleus/cytoplasm(N/C)ratio, the number of granules with different sizes and electron-density of their cytoplasmic granules, three types of haemocytes were recognized in adult Neomysis japonica: type 1 hyaline cells(no cytoplasmic granule), type 2 semigranular cells(a few cytoplasm granule), type 3 granular cells(abundant granules in cytoplasm). The proportion of the three types were analyzed depending on Wright’s smears, and the result indicated that the proportion of haemocytes(47.53%±0.02) was the largest, while that of hyalinocytes(21.24%±0.02) the smallest. The size was increased from type 1 to type 3, however, the N/C rate was decreased. The activites of acid Phosphatase(ACP), alkaline phosphatase(AKP), lysozyme(LYZ), and phenoloxidase(PO) were analyzed by biological and chemistry methods in total body of Neomysis japonica on 0 d，10 d， 20 d， 30 d after being hatched，respectively. The activities of ACP， AKP, LYZ, PO were decreasing with the growth of individuals．The activity of LYZ was 305.20 U/mg Prot on average, the highest in the three enzymes； the second is ACP, at 0.236 5 U/mg Prot； The activities of PO and ACP were almost the same at 0.129 5 U/mg Prot in adult N. japonica．In conclusion, hyaline cells were mainly haemocytes type in adult N. japonica．In addition, lysozyme played a siginificant role in immune process of N. japonica．The activities of ACP, AKP, LYZ, PO were decreasing gradually with the individual development．