Culture system impact on fatty acids and amino acids accumulation in tiger pufferfish (Takifugu rubripes)

Abstract

Tiger pufferfish (Takifugu rubripes) is considered to be the most nutritionally valuable aquaculture species due to its high protein and collagen content. In this study, the fatty acids and amino acids (AAs) of the muscle and skin of tiger pufferfish reared in an offshore sea cage aquaculture system (OSCS) and a recirculating aquaculture system (RAS) were examined to illustrate the possible differences between the two systems. Results showed that the saturated fatty acid (SFA), arachidonic acid, and polyunsaturated fatty acid (PUFA) content of tiger pufferfish reared in the OSCS were significantly higher than those of pufferfish reared in the RAS. Meanwhile, the contents of C14:0, C16:1n-7, C18:1, and C18:2 were significantly higher in the muscle of male pufferfish than in females. The fatty acid content in the skin of tiger pufferfish manifested similar results in the muscle, and pufferfish raised in the OSCS obtained higher values of SFA, PUFA and monounsaturated fatty acid than did pufferfish reared in the RAS. The docosahexaenoic acid and eicosapentaenoic acid content in the skin of male pufferfish were significantly higher than those of females reared in the RAS, whereas there was no significant difference between male and female fish reared in the OSCS. Essential amino acid (EAA), non-essential amino acid (NEAA), and flavor amino acid (FAA) content in the muscle and skin of pufferfish reared in the OSCS were significantly higher than those of fish reared in the RAS. However, EAA content in the muscle and skin of pufferfish reared in the two aquaculture systems showed no significant difference. EAA, NEAA, and FAA content in the muscle and skin of male tiger pufferfish were higher than those of female pufferfish reared in the RAS, whereas no significant difference was observed in male and female pufferfish reared in the OSCS. The interaction effects of gender and rearing system on fatty acid and AAs content in the muscle and skin of tiger pufferfish were observed. In conclusion, the accumulation of fatty acids and AAs in OSCS-raised tiger pufferfish was higher than that in RAS-raised fishes, and male tiger pufferfish had a significant advantage. These findings provide the basic data and will be helpful in developing new strategies for enhancing the flesh quality of tiger pufferfish through the combined land-sea (RAS-OSCS) relay model in captivity.