Gisbert E, Villeneuve L, Zambonino-Infante J L, Quazuguel P, Cahu C L
Centre d'Aqüicultura, Institut de Recerca i Tecnologia Agroalimentaries, Tarragona, Spain.
Lipids. 2005 Jun;40(6):609-18. doi: 10.1007/s11745-005-1422-0.
We evaluated the effects of dietary lipid class (phospholipid vs. neutral lipid) and level of n-3 long-chain PUFA (LC-PUFA) on the growth, digestive enzymatic activity, and histological organization of the intestine and liver in European sea bass larvae. Fish were fed from the onset of exogenous feeding at 7 to 37 d post-hatch with five isoproteic and isolipidic compound diets with different levels of EPA and DHA. Diet names indicated the percentage of EPA and DHA contained in the phospholipids (PL) and neutral lipids (NL), as follows: PL5, PL3, PL1, NL1, and NL3. Histological observations showed different patterns of lipid absorption and accumulation in the intestinal mucosa depending on the level and nature of the dietary lipid fraction. Fish fed high levels of neutral lipids (11%, NL3 diet: 2.6% of EPA + DHA in the NL fraction) showed large intracellular and intercellular lipid deposits in the anterior intestine, but no such lipid accumulation was detected when larvae were fed with low and moderate levels of EPA and DHA in the phospholipid and neutral lipid fractions of the diet (PL and NL1 diets). PL were preferentially absorbed in the postvalvular intestine, and the accumulation of marine PL was inversely correlated to their dietary level. The postvalvular intestinal mucosa and liver showed signs of steatosis; large lipid vacuoles were observed in this region of the intestine and in the liver and were inversely correlated with the level of dietary neutral lipids. The best results in terms of growth, survival, and development (maturation of the digestive system and histological organization of the liver and intestinal mucosa) were obtained in the group fed with 2.3% of EPA and DHA in the PL fraction of the diet (PL3 diet), revealing that European sea bass larvae use the LC-PUFA contained in the PL fraction more efficiently than those from the NL fraction of the diet.
我们评估了日粮脂质类别（磷脂与中性脂质）和n-3长链多不饱和脂肪酸（LC-PUFA）水平对欧洲海鲈幼鱼生长、消化酶活性以及肠道和肝脏组织学结构的影响。从孵化后7天开始外源投喂至37天，用五种等蛋白、等脂质且具有不同二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）水平的复合日粮喂养幼鱼。日粮名称表明了磷脂（PL）和中性脂质（NL）中所含EPA和DHA的百分比，如下：PL5、PL3、PL1、NL1和NL3。组织学观察表明，根据日粮脂质部分的水平和性质，肠道黏膜中脂质吸收和积累的模式有所不同。投喂高水平中性脂质（11%，NL3日粮：NL部分中EPA + DHA含量为2.6%）的幼鱼在前肠出现大量细胞内和细胞间脂质沉积，但当幼鱼日粮的磷脂和中性脂质部分（PL和NL1日粮）中EPA和DHA含量低和中等时，未检测到此类脂质积累。PL优先在后瓣膜后肠道被吸收，海洋PL的积累与它们的日粮水平呈负相关。后瓣膜后肠道黏膜和肝脏出现脂肪变性迹象；在肠道的该区域和肝脏中观察到大量脂质空泡，且与日粮中性脂质水平呈负相关。在日粮PL部分含有2.3% EPA和DHA的组（PL3日粮）中，在生长、存活和发育（消化系统成熟以及肝脏和肠道黏膜的组织学结构）方面取得了最佳结果，这表明欧洲海鲈幼鱼利用日粮PL部分中所含LC-PUFA的效率高于NL部分中的LC-PUFA。
