正常和白化褐牙鲆皮肤和肌肉中DHA和EPA含量的比较

利用气相色谱法对相同养殖条件下生长的正常和白化褐牙鲆(Paralichthys olivaceus)的皮肤和肌肉组织中的DHA和EPA含量进行了比较分析。结果显示，正常和白化褐牙鲆的皮肤和肌肉中EPA含量相近，但白化个体皮肤中DHA含量显著低于正常个体，约为后者的1／2。而两者肌肉中的DHA含量则没有显著差异。同时，白化个体皮肤和肌肉组织中的DHA／EPA比值略低于正常个体。这一结果证明白化褐牙鲆皮肤蓄积或利用DHA的能力要低于正常褐牙鲆。关于鲆鳔类白化现象同鱼体对饵料中脂肪酸类物质的利用率之间的关系有待深入研究。

Comparisons of DHA and EPA contents in skin and muscle between normal and albino Paralichthys olivaceus

In this study, the variations of contents of DHA (22:6n-3) and EPA (20:5n-3) in the skin and muscle of normal and albino Japanese flounder growing under the same environment and fed with the same diets were determined by using gas-chromatographer. The results showed that the contents of EPA are similar in the skin and muscle of both normal and albino fish, while the content of DHA in the skin of albino fish is significantly lower than that in the skin of normal fish. The contents of DHA in muscle of normal and albino fish show no difference. Moreover, the ratios of DHA/EPA in the skin and muscle of albino fish are a little lower than those in the skin and muscle of the normal ones. So we suggest that the skin of albino fish has low capability of cumulating and utilizing DHA. This result is helpful for further understanding the utilization of fatty acids in fish bodies, and evaluating the effects of diets enriched with n-3 unsaturated fatty acid in reducing the albinism of flatfish.