黄条鰤不同组织碳稳定同位素的转化率与分馏

摘要

In this study,the conversion difference and ffactionation coefficient of carbon stable isotope in different tissues were investigated in yellow tail Seriola aureovittata with body weight of (34.2± 1.8) g fed diets containing detected carbon source by stable isotope technique in a laboratory condition at water temperature of 18.79 ～ 22.15 ℃C in order to understand the effects of tissue growth and metabolism on the relative contribution of the carbon stable isotope conversion in different tissues of yellow tail.The results showed that the minimal half-life of carbon stable isotope was observed in liver (3.2 d),followed by intestine (3.4 d),gill (3.6 d),heart (5.5 d),and muscle (6.4 d),and that the minimal enrichment coefficients of carbon stable isotope in liver and diet (0.15‰),followed by intestine (0.48‰),heart (0.98‰),gill (1.02‰) and muscle (1.08‰).The higher stable isotope conversion rates in liver and intestine were involved in high metabolic rate (＞ 60％),thus relatively less contribution to growth.Liver and intestine can reflect the isotope alteration during the assimilation of dietary carbon in short-term feeding,while the muscle reflects the isotope alteration of long-term feeding.The findings improved the biology of yellow tail,and provided information for the stable isotope sample collection at different period,diet enrichment and selection in the aquaculture industry.%在水温18.79～22.15℃的实验室条件下,给体质量(34.2±1.8)g的黄条鰤Seriola aureovittata投喂已知碳源的冰鲜玉筋鱼Ammodytes personatus肌肉,研究黄条鰤不同组织碳稳定同位素的转化率差异及分馏系数,以探讨组织生长和代谢对不同组织碳稳定同位素转化的相对贡献.结果表明,黄条鰤各组织碳稳定同位素半衰期从小到大依次为肝脏(3.2d)、肠(3.4d)、鳃(3.6d)、心脏(5.5d)、肌肉(6.4d),各组织与饵料间的碳稳定同位素富集系数(△δ13C)从小到大依次为肝(0.15‰)、肠(0.48‰)、心脏(0.98‰)、鳃(1.02‰)、肌肉(1.08‰).代谢作用对肝脏和肠组织的碳稳定同位素转化率的贡献占主导地位(＞60％),生长作用对其贡献相对较小.肝脏和肠组织可反映黄条鰤短期内的摄食特征,而肌肉组织则可反映较长时间的摄食特征.本研究结果可丰富黄条鰤基础生物学内容,为不同时间尺度的稳定同位素研究取样和工厂化养殖中的营养强化、饵料选择等提供参考.