凡纳滨对虾亲虾常用天然饵料营养成分的比较研究

A COMPARATIVE STUDY ON BIOCHEMICAL COMPOSITION OF MAIN NATURAL DIETS FOR BROODSTOCK LITOPENAEUS VANNAMEI

分析比较了凡纳滨对虾亲虾培育中 4 种常用天然饵料———长吻沙蚕 Glycera chirori 、双齿围沙蚕Perinereis aibuhitensis、近江牡蛎Crassostrea rivularis (去壳)和杜氏枪乌贼Lol igo duvancelii 的营养成分及组成。结果表明,杜氏枪乌贼的蛋白质(78. 41%)和胆固醇(16.1 mg·g-1 )含量最高;双齿围沙蚕的 EPA 和 DHA 含量最高(分别为 14. 15%和12.97%),∑n 3/∑n 6值为5. 79;长吻沙蚕的 EPA和 DHA含量略低(分别为 12. 36%和11.54%),但其∑n 3/∑n 6值最高,为 7.06;长吻沙蚕的α 生育酚含量最高,为 47.72mg·kg-1,以下依次为双齿围沙蚕(43.02mg·kg-1 )、近江牡蛎(42.31mg·kg-1 )、杜氏枪乌贼(38.93mg·kg-1)。双齿围沙蚕具有最高的抗坏血酸含量,为 110.12mg·kg-1,以下依次为长吻沙蚕(100.06mg·kg-1)、杜氏枪乌贼(91.41mg·kg-1 )、近江牡蛎(33.75mg·kg-1 )。通过比较这些天然饵料的营养组成并结合已有研究结果,认为杜氏枪乌贼具有较高的蛋白质和胆固醇含量及理想的氨基酸组成,是凡纳滨对虾亲虾的优质蛋白质和胆固醇来源;而长吻沙蚕和双齿围沙蚕具有高含量的EPA和DHA,以及更高的∑n 3/∑n 6值,是凡纳滨对虾亲虾的最佳高度不饱和脂肪酸来源。此外,2 种沙蚕的α 生育酚和抗坏血酸含量较高。

This study was conducted to evaluate nutritional values of the main natural diets for broodstock Litopenaeus vannamei. Four natural diets, Crassostrea rivularis, Loligo duvancelii, Perinereis aibuhitensis and Glycera chirori were analyzed, and the biochemical composition was presented. The results showed that these natural diets have almost the same amino acid and fatty acid patterns; a great difference, however, was found in the concentrations of protein, total lipid, cholesterol, α-tocopherol and ascorbic acid, as well as in the compositions of essential amino acids (EAA) and highly unsaturated fatty acids (HUFA). Based on the above results, we came to the conclusion that L. duvancelii, with its rich contents of protein and cholesterol as well as the excellent amino acid composition, is the optimal protein and cholesterol sources for broodstock L. vannamei; while P. aibuhitensis and G. chirori, with higher levels of EPA, DHA and ∑n-3HUFA to ∑n-6HUFA ratio than C. rivularis and L. duvancelii, may be responsible for their outstanding effect on triggering maturation. Furthermore, higher concentrations of α-tocopherol and ascorbic acid in these two clamworms may also contribute to the promotion of ovarian maturation and egg quality of L. vannamei. But the optimum levels of these vitamins for shrimp broodstock could not be determined in this study.