3种植物油源对军曹鱼生长、体组成和脂肪酸组成的影响

Impact of Three Vegetable Oil Sources on Growth,Body Composition and Tissue Fatty Acid Composition of Juvenile Cobia(Rachycentron canadum)

开展了一个8周的饲养试验以评价3种植物油(大豆油,菜籽油和亚麻油)对军曹鱼幼鱼的生长、体组成和组织脂肪酸组成的影响。配制了4种等氮(饲料干重含46%蛋白)等能的饲料,对照组是海水鱼油,每组设3个平行,每个平行有15尾初始重(10.29±0.22)g的军曹鱼幼鱼。结果提示军曹鱼幼鱼无法通过饲料补充18:2n-6或18:3n-3来满足对EFA,的需求。投喂植物油饲料的军曹鱼肌肉被有显著高含量的LA所特征,这意味着使用植物油饲料降低了军曹鱼产品的品质。

A 8-week feeding experiment was conducted to investigate the effects of dietary vegetable oils on growth, body composition and tissue fatty acid profiles of juvenile cobia. Four isonitrogenous diets containing 10% of added marine fish oil （MFO）, soybean oil （SO）, rapeseed oil （RO） or linseed oil （LO） were fed to triplicate groups of 15 fish （initial body weight： 10.29±0.22 g） grown in sea water at the temperature of 28.9±1.5 ℃. After 56 days, growth rates of cobia fed the VO diets were low and probably reflective of a lack of sufficient essential fatty acids. Tissue fatty acid compositions of fish were directly reflected by dietary fatty acid composition, but a selective reserve of essential fatty acids was observed. The percentages of flesh 20：5n-3 and 22：6n-3 were higher in fish fed VO compared to them in diets. The percentages of flesh 20：5n-3 were not significantly different among treatments, while percentages of 22：6n-3 were significantly lower in fish fed VO （5.15%-9.10%） compared to fish fed FO（10.84%）. Although 20： 4n-6（AA） was scarce in diets containing vegetable oil, AA muscle contents of these fish in LO, SO and RO groups （2.97% ,2.06% and 2.92%, respectively） were higher than their content in the respective diet. The results suggest that juvenile cobia hadapparently absolute requirement of dietary DHA, EPA and AA for growth in the present experiment. High deposition of flesh 18：2n-6 in fish fed VO is disadvantage for human nutrition.