Comparison of reproductive performance, embryo color and biochemical composition of white and green carapace strains of Chinese mitten crab (Eriocheir sinensis)

To investigate the reproductive performance of a new white carapace strain of Chinese mitten crab (Eriocheir sinensis), we compared the breeding experiments and gastral embryo quality of white and green carapace strains in indoor tanks. The results show that the ovigerous rate, survival rate and spawning rate of the white carapace strain were higher than those of the green carapace strain, but the egg production, fecundity and reproductive effort of the white carapace strain were slightly lower than those of the green strain. There were no significant differences in the egg diameter, wet and dry mass of single egg between the two strains (P>0.05). In addition, no significant differences were found in the color parameters in dried eggs (P<0.05) and the contents of total carotenoids, zeaxanthin, canthaxanthin and β-carotene in both strains were similar (P>0.05), but the contents of astaxanthin and lutein in dried eggs in the white carapace strain were significantly lower than those in the green carapace strain (P<0.05). Besides, the eggs of both strains had similar moisture, total lipid and crude protein contents (P>0.05). As for fatty acid composition of eggs, the percentage of C18:1 n-9 in the white carapace strain was significantly higher than that in the green carapace strain (P<0.05), but there were no significant differences in other fatty acid contents (P>0.05). In conclusion, the female ovigerous rate of the white carapace strain is faster than that of the green carapace strain, but the reproductive performance, eggs color and proximate composition are similar.