Comparative analysis of nutrients in muscle and ovary between an improved fish and its parents

In previous studies, an allodiploid lineage (WR-F1-F5) was established by the distant hybridization of white crucian carp (Carassius cuvieri, WCC, ♀) and red crucian carp (Carassius auratus red var., RCC, ♂), an allodiploid fish (WR-II) was produced by WR-F1 (♀) × WCC (♂). In this study, the nutrients in the muscle and ovary of WR-II and its parents (WCC, RCC, and WR) were investigated, including protein, fat, amino acid, docosahexaenoic acid (DHA), moisture, and ash. The results showed that the protein content of WR-II in muscle and ovary (17.90 % and 25.60 % respectively) was higher than that of WR, and was significantly higher than that of WCC and RCC (p < 0.05). The fat content of WR-II in muscle and ovary (4.30 % and 5.31 % respectively) was higher than that of WR and was significantly higher than that of WCC and RCC (p < 0.05), and the muscle and ovary of WR-II showed rich DHA content (0.32 % and 0.54 % respectively) than that of WCC and RCC (p < 0.05). Fifteen amino acids were detected in WR-II and its parents, the total amino acid (TAA) content of WR-II in muscle and ovary (15.49 % and 18.43 % respectively) was significantly higher than that of WCC (p < 0.05), the delicious amino acid (DAA) content of WR-II in muscle and ovary (6.56 % and 8.29 % respectively) was different degrees higher than that of WCC, RCC, and WR. The moisture and carbohydrates of WR-II in muscle and ovary were lower than those in WCC and RCC. Furthermore, protein, fat, TAA, and DAA content in the ovary were significantly higher than those in muscle (p < 0.05), showing tissue differences in all detected fish. This study indicated that WR-II had the characteristics of high protein, high fat, high DHA, high TAA, high DAA, low moisture, and low carbohydrates, which provided theoretical support for its application.