饲料中棕榈油替代鱼油和豆油对黄颡鱼生长和肌肉脂肪酸组成的影响

为研究不同棕榈油替代水平对黄颡鱼生长性能、肌肉脂肪酸组成、形体指标和肝脏组织结构的影响, 实验采用5组等氮(400 g/kg)等脂(100 g/kg)等能(15.70 MJ/kg)饲料饲喂黄颡鱼(16.15±0.04) g], 对照饲料以鱼油鲶豆油1鲶2混合为脂肪源, 实验饲料以棕榈油分别替代10、25、40和55 g/kg的混合脂肪源。经过8周的养殖实验, 结果表明棕榈油替代水平对黄颡鱼的摄食量、终末体重、特定生长率、饲料效率和蛋白沉积率未产生显著性的影响(P>0.05), 但是上述指标均呈现先升高后略微下降的趋势, 并在25 g/kg替代组达到最大值。背肌肌肉中亚油酸和n-3HUFA含量随着棕榈油替代水平的上升而显著下降(P<0.05), 但n-3/n-6比值随着棕榈油替代水平的上升而显著上升(P<0.05), 棕榈油替代水平对各组黄颡鱼的肥满度和脏体比未产生显著性的影响(P>0.05), 但是55 g/kg棕榈油替代水平组肝体比显著高于25 g/kg棕榈油添加组(P<0.05), 且55 g/kg棕榈油替代水平组黄颡鱼的肝脏组织出现细胞肿胀, 细胞核移位, 肝血窦和脂肪细胞数量明显增多等不良影响。据上所述: 对于黄颡鱼幼鱼, 棕榈油可以替代25 g/kg的混合脂肪源(鱼油鲶豆油=1鲶2)不影响鱼体生长性能并且在一定程度上改善了背肌肌肉脂肪酸组成。

EFFECTS OF SUBSTITUTING PALM OIL FOR FISH OIL AND SOY OIL IN FEED ON THE GROWTH PERFORMANCE AND MUSCULAR FATTY ACID COMPOSITION OF PELTEOBAGRUS VACHELLI

To investigate the effects of dietary replacement of fish-soy oil mixtures by palm oil on growth performance, feed utilization, muscular fatty acid composition, morphological index and liver tissue structure of yellow catfish (Pel-teobagrus vachelli Richardson), five iso-proteic (400 g/kg), iso-lipidic (100 g/kg) and iso-energetic (15.70 MJ/kg) diets were formulated, in which the control group was supplemented with 1:2 fish-soy oil mixtures, and trial groups adopted different palm oil level (10 g/kg, 25 g/kg, 40 g/kg and 55 g/kg) to replace the mixture oil, respectively. For a 8-week trial. The results showed that dietary palm oil replacement had no significant effect on the feed intake, body weight, growth rate, feed efficiency, and protein retention efficiency (P>0.05). All the above parameters were increased with in-creasing dietary palm oil replacement level up to 25 g/kg, and then decreased. LA and n-3 HUFA concentrations in dorsal muscle significantly decreased with increasing dietary palm oil replacement level (P<0.05), while muscular n-3/n-6 significantly increased with increasing dietary palm oil replacement level (P<0.05). Furthermore, there were no significant difference in condition factor and viscerosomatic index among different groups (P>0.05). However, hepato-somatic index of 55 g/kg palm oil group was significantly higher than that of 25 g/kg palm oil group (P<0.05). The swelling hepatocytes with nuclei displacement and the increasing number of hepatic sinusoid and lipid cells were ob-served in 55 g/kg palm oil group. In conclusion, palm oil that replace 1:2 fish-soy oil mixtures up to 25 g/kg had no sig-nificant effect on the growth performance but improved the fatty acid profile of dorsal muscle.