Interactions of dietary eicosapentaenoic acid and vitamin C on growth performance, anti-oxidation and muscle quality of abalone Haliotis discus hannai Ino

A 93-day feeding trial was conducted to investigate the effects of dietary eicosapentaenoic acid (EPA) and vitamin C (VC) on the growth performance, anti-oxidation and muscle quality of abalone Haliotis discus hannai (initial body weight: 26.89 +/- 0.26 g; initial shell length: 60.36 +/- 0.25 mm). Six experimental diets in a 3 x 2 two-factor design were formulated with graded levels of dietary EPA (0.25%, 0.75% and 1.25%) and dietary VC (0 and 1260 mg/kg). Results showed that the weight gain rate (WGR) of abalone was significantly increased with the increasing dietary EPA levels (P < 0.05), but there was no significant effect of dietary VC on the WGR. The significant highest superoxide dismutase (SOD) activity was observed in the group with 1.25% of dietary EPA and 1260 mg/kg of dietary VC, and there was a significant interaction between dietary EPA and VC (P < 0.05). Dietary EPA supplementation significantly improved muscle hardness and the content of n-ary sigma(n-3) polyunsaturated fatty acids, volatile compounds, adenosine-5'-monophosphate (AMP) and inosine-5'-monophosphate (IMP) in muscle. Dietary VC supplementation significantly improved the muscle hardness, springiness, chewiness, and the contents of volatile compounds, hydroxyproline and IMP in muscle (P < 0.05). Significant interactions between dietary EPA and VC were observed on volatile compounds, AMP and IMP (P < 0.05). In conclusion, dietary EPA and VC interactively influence the anti-oxidative capability and muscle quality of abalone.