Abstract：Abstract In order to study the feasibility of injecting Chinese shrimp (Fenneropenaeus chinensis) total DNA into common carp (Cyprinus carpio) and its effects on muscle nutritional composition of experimental carp, total DNA of Chinese shrimp was fragmented and injected into oosperm of common carp to breed a batch of microinjection offspring. The amplified fragment length polymorphism (AFLP) detection showed that all F2 generation of microinjection contained exogenous gene fragments from the total DNA of Chinese shrimp genome. Furthermore, PCR experiments were conducted using E-AAG and M-CTC primers to detect the Chinese shrimp DNA fragments, which presence in F2 generation of microinjection carp, but absent in control group of carps. Results showed that Chinese shrimp gene fragments had been incorporated into the genome of microinjection carp offspring and can be stably transmitted to the progeny generation. Based on the confirmation of genetic stability of exogenous gene, nutrient content and metal content were tested in the muscle of F2 generation. The results showed that crude protein, fat content and ash content in muscle of microinjection carp showed significant difference in that of control carp. Crude protein content was 18.37% in microinjection carp and 16.49% in control carp, respectively. Fat content was 2.49% in microinjection carp, and it was lower than 3.51% in control carp. Ash content was 1.17% in microinjection carp, and it was higher than 1.05% in control carp. Total amino acid content was 79.92% and 74.16% in microinjection carp and control carp, respectively. Of which, glutamic acid was the highest amino acid in all the 17 tested amino acids, accounting for 16.60% and 16.22% of the total amino acid, with a percentage of 13.27% and 12.03% in microinjection carp and control carp, respectively. The top 5 amino acids in microinjection carp were glutamic acid, aspartic acid, lysine, leucine and alanine, which were consistent with that in control carp. These results suggested that there was no differences in amino acid composition between microinjection carp and common carp. The delicious amino acid was 31.16% in microinjection carp, and it was 28.04% in control carp, accounting for 38.99% and 37.81% of the total amino acid, separately. In addition, tryptophan, isoleucine, leucine, threonine, valine, methionine, phenylalanine and lysine were another 7 essential amino acids in 18 amino acids. The essential amino acid content was 31.5% and 29.54% in microinjection carp and control carp, accounting for 39.41% and 39.83% of total amino acids, respectively. The limited amino acid was valine in both microinjection carp and control carp. Above all, microinjection carp had certain advantages in nutrients when compared to common carp. Amino acid score (AAS), chemical score (CS) and essential amino acid index (EAAI) were computed by converting the amino acid content into amino acid weight per gram of nitrogen following by the standard evaluation of protein made by FAO/WHO and the amino acid pattern of egg protein. The content of heavy metals including Cu, Zn, Cr, Hg, Cd and Pb in both microinjection carp and common carp met the requirements of relevant food safety standards. This study provides a basis for the commercialization of microinjection carp.
