Evaluation of four macro-algae on growth performance, anti-oxidant capacity and non-specific immunity in golden pompano (Trachinotus ovatus)

Abstract

A nutritional feeding experiment was conducted to determine growth performance and antioxidant capacity in T. ovatus. Five diets were formulated (D1, control; D2, Saccharina japonica; D3 Undaria pinnatifida; D4 Gracilaria lemaneiformis; D5, Porphyra haitanensis) to feed fish for 8 weeks. Results showed that final body weight and weight gain in D3 and D5 groups were significantly higher than D1 and D4 groups (P < 0.05), while made no significant difference with D2 group (P > 0.05). Feed conversion ratio in D5 group was significantly lower than D1 group (P < 0.05), while made no significant difference with other groups (P > 0.05). Feed intake and survival rate showed no significantly difference among all groups (P < 0.05). The relative expression level of digestion related genes including chymotrypsinogen and carnitine palmitoyltransferase 1 in D5 group was significantly higher than other groups (P < 0.05). The expression level of anti-oxidant related genes such as, catalase in D5 group was significantly higher than that in D2 and D4 groups (P < 0.05); while expression of nuclear factor erythroid 2-related factor 2 in D5 group was significant higher than that in D1 groups (P < 0.05). The mRNA expression of non-specific immunology related gene c-Llysozyme in D5 group were significantly higher than any other groups (P < 0.05). Villi length in fish fed diets with macro-algae were significantly longer than control diet (P < 0.05). Muscle thickness in D5 group were significantly higher than D1, D2 and D4 groups, while showed no significant difference with D3 group (P < 0.05). The results indicated that P. haitanensis is the most suitable macro-algae and then followed by U. pinnatifida as the feed additive for Trachinotus ovatus.