We studied the effect of natural xanthophyll and artificial canthaxanthin in diet on the body color of yellow catfish (Pelteobagrus vachelli Richardson) in a 60-day experiment,during which 11 fish groups (30 individuals each group)were fed xanthophyll at 0,25,50,100,200mg/kg,xanthophyll at 25,50,100mg,and canthaxanthin at 25,50mg/kg in base diet.The initial body weight of fish in test groups was (10.0 ± 0.3)g in average.The results indicate that the final body weight offish reached (22.3 ± 1.8)g in average and no significant difference among test groups (P＞0.05).The body color of fish in test groups 3,8,9 (xanthophyll 50mg/kg; xanthophyll 50mg/kg,and canthaxanthin 25,50mg/kg in base diet) are similar to the wild ones,showing no significant difference in the content of xanthophyll in skin among them (P＞0.05).Therefore,adding natural xanthophyll in diet is much better in acquiring natural color by the fish than artificial canthaxanthin; and xanthophyll shall be a suitable pigment in feed for yellow catfish culture at optimal ratio of 50mg/kg.%采用传统养殖试验方法研究了日粮中添加叶黄素与角黄素对瓦氏黄颡鱼(Pelteobagrus vachelli Richardson)体色的影响.实验设计了11组等蛋白质(42.6％)、等能量(18.5MJ/kg)的实用试验日粮,在试验日粮中分别添加0、25、50、100、200mg/kg叶黄素和25、50、100mg/kg叶黄素与25、50mg/kg角黄素,对照组为野生瓦氏黄颡鱼.结果表明,实验结束时(60d),试验3、8、9日粮组(添加50mg/kg叶黄素、50mg/kg叶黄素+25mg/kg角黄素、50mg/kg叶黄素+25mg/kg角黄素)鱼体体色与对照组鱼(野生瓦氏黄颡鱼)体色相似,试验3、8、9组鱼皮肤中叶黄素含量与对照组鱼差异不显著(P＞0.05).本实验认为,在日粮中添加叶黄素对瓦氏黄颡鱼的着色效果明显较角黄素好,是养殖瓦氏黄颡鱼饲料的适宜添加色素.在瓦氏黄颡鱼的饲料中叶黄素的建议添加量为50mg/kg.
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