COMPOSITION AND VARIATION OF AMINO ACID AND FATTY ACID IN FERTILIZED EGGS AND LARVAE OF SEBASTISCUS MARMORATUS IN DIFFERENT DEVELOPMENTAL STAGES
GUO Chung-Yang;LIN Shao-Zhen;GONG Jian-Hua;QIU Cheng-Gong;ZHAO Chun;XU Shan-Liang;School of Marine Sciences, Ningbo University;Zhejiang Mariculture Research Institute;
To investigate amino acids and fatty acid composition and changes of Sebastiscus marmoratus in different development stages. Amino acids and fatty acid composition of the fish in four stages(fertilized eggs, first larvae fish, prophase larvae fish, and late stage larvae fish) were analyzed in GC/MS. Five results were followed.(1) The total amino acid content decreased significantly from fertilized eggs to first larvae fish stage, then increased significantly during prophase larvae fish stage, and finally decreased significantly again in late stage larvae fish(P0.05).(2) The total amount of free amino acids during first larvae fish was the highest among the four stages, which was 10 times of the fertilized eggs. The ratio of free amino acids each stage was 1.4%—20.0%.(3) The maximum content was DHA(104.88 mg/g) and C16:0(68.74 mg/g) in fertilized eggs, followed by C18:1n-9(41.23 mg/g) and EPA(27.23 mg/g).(4) The main fatty acid selective consumed during endogenous vegetative stage of S. marmoratus was in the sequence of C16:0C18:1 EPADHAARA, and MUFASFAPUFA for the utilization of fatty acid.(5) The fatty acid utilization was in sequence of PUFASFAMUFA during exogenous vegetative stage after weaning larvae, of which DHA was selectively consumed compared to EPA and ARA. We found that the ratio of free amino acid in the fertilized eggs accorded with features of demersal eggs of marine fishes, showing different selectivity when the fish consumed fatty acid during different early development stages. C16:1, C16:0, C18:0 and C18:1 are main energy substances during early development stage. Therefore, it is necessary to enrich the diet with a certain level of amino acids, such as isoleucine, leucine, tyrosine, etc. as well as polyunsaturated fatty acids DHA.