| 摘要: |
| 以鱼粉和酪蛋白为蛋白源，玉米淀粉为糖源，以豆油分别替代25%、50%、75%和100%的鱼油，配制4组等氮（50.26%-51.03%）、等能（20.82-21.01kJ/g）实验饲料，每组饲料设3个平行，每个平行20尾鱼，进行为期6周的生长实验。实验结果表明，过高的豆油替代会引起生长的下降。随着豆油替代水平的升高，饲料转换系数（FCR）呈现先下降后上升的趋势，最高值（1.96±0.42）出现在全豆油替代水平组，而蛋白质效率（PER）表现为相反的结果。全豆油替代组呈现相对最高的肝体比（HSI）值，但各处理组之间没有显著性差异（P>0.05）。全鱼水分和蛋白含量没有明显差异（P>0.05）。投喂25%替代水平组的全鱼脂肪含量最高（P<0.05），但是在50%-100%替代水平处理组之间没有显著差异（P>0.05）。赤点石斑鱼鱼体脂肪酸组成明显受到饲料脂肪酸组成的影响。随着饲料豆油水平的升高，全鱼鱼体中的亚油酸（C18：2n6）含量显著升高（P<0.05），ARA（C20：4n6）、EPA（C20：5n3）和DHA（C22：6n3）含量在全豆油替代组最低。总之，饲料豆油替代水平不宜超过75%，过高的豆油替代水平可能会对赤点石斑鱼生长产生不利影响，并影响鱼的品质。 |
| 关键词: 赤点石斑鱼 饲料替代 生长 体脂肪酸 |
| DOI：10.11693/hyhz20160300054 |
| 分类号: |
| 基金项目:浙江省自然科学基金项目，LY16C190005号；浙江省国际科技合作项目，2015C34002号；浙江省科技计划项目，2015C33089号；舟山市科技计划项目，2014C41009号。 |
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| EFFECTS OF DIETARY FISH OIL REPLACEMENT BY SOYBEAN OIL ON GROWTH PERFORMANCE, BODY COMPOSITION AND BODY FATTY ACID COMPOSITION OF RED SPOTTED GROUPER EPINEPHELUS AKAARA |
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WANG Ji-Teng, JIANG Yu-Dong, YANG Yun-Xia, HAN Tao, YANG Min, ZHENG Pu-Qiang, SHENG Jian-Hai
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Aquaculture Department of Zhejiang Ocean University, Zhoushan 316022, China
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| Abstract: |
| A 6-week experiment was conducted to investigate the effects of dietary fish oil replacement by soybean oil on growth performance, body composition, and body fatty acid composition of red spotted grouper Epinephelus akaara. Four isonitrogenous (crude protein 50.26%-51.03%) and isoenergetic (20.82-21.01kJ/g) experimental diets were formulated with soybean oil replacing 25%, 50%, 75%, and 100% fish oil, respectively. Grouper were randomly distributed into four triplicate groups (20 fish per group). The results show that with the increase of soybean oil content, FCR (food conversion factor) decreased and then increased. The highest FCR value (1.96±0.42) occurred in the group of entire replacement by soybean oil. However, the PER (protein efficiency ratio) value showed an inverse tendency with FCR. The entire replacement treatment showed a relatively high HSI (hepatosomatic index) value, but no significant different was observed among treatments (P>0.05). In addition, no significant impact was shown on whole body moisture and protein regardless of soybean oil replacement level (P>0.05), except that those fed with 25% replacement of soybean oil showed the highest whole body lipid content (P<0.05). No apparent correlation occurred with the dietary replacement in body fatty acid composition. The content of C18:2n6 significantly increased (P<0.05) with increase in dietary soybean oil level; and the lowest ARA (C20:4n6), EPA (C20:5n3), and DHA (22C:6n3) contents occurred in 100% soybean oil group. Therefore, the level of soybean oil replacement should be kept below 75%. |
| Key words: red spotted grouper Epinephelus akaara dietary replacing growth performance body fatty acid composition |
