Abstract:In order to understand the effects of female body weight of giant freshwater prawn (Macrobrachium rosenbergii) on their reproductive performance and embryo quality, the reproductive performance, embryo quality, and egg colouration of four sizes of female M. rosenbergii broodstock (A: 16-20 g/tail, B: 24-28 g/tail, C: 32-36 g/tail, D: 40-44 g/tail) were compared in this study, and the correlation between body weight and reproductive performance was also analyzed. The results showed that while the body weight of giant freshwater prawn broodstock increased, the amount of egg production increased significantly. The egg production of group D was significantly higher than that of group A, B and C, while that of group C was significantly higher than that of group A. The reproduction and reproductive index also increased with the increase of body weight, with group D significantly higher than group A. However, there was no significant difference among groups A, B and C, and among groups B, C and D. There was no significant difference in wet weight, dry weight and diameter of single egg among the groups, as well as the embryo color parameters. The body weight of giant freshwater prawn broodstock exhibited significant positive correlation with egg production (r=0.847,P=0.000), fecundity (r=0.508,P=0.004), and reproductive effort (r=0.551,P=0.001). In conclusion, the reproductive performance of larger size of giant freshwater prawn broodstock was better than that of smaller size, but the size had no obvious influence on embryo quality. These results could provide valuable information for the broodstock selection, evaluation of reproductive performance and artificial breeding of giant freshwater prawn in the future.