A 6-week experiment was conducted to determine the optimum feeding frequency for gastric evacuation, growth performance and body composition of juvenile Darkbarbel catfish （Pelteobagrus vachelli Richardson）. At the start and end of the feeding trial, gastric evacuation rate of the fish was monitored after feeding. Gastric evacuation of fish was best fitted with square root model. By the square root model of GER, it was estimated that evacuation would require 36-40h reaching the pre-feeding level and 95% evacuation would require 32-36h, which suggested the return of appetite Three replicate groups of fish （average weight of 5.9 g）were fed to visual satiety with pellet feed at different feeding frequencies （three meals a day, two meals a day, one meal a day, two meals every 2 days or one meal every 2 days）： Weight gains and feed intakes of the fish fed triple a day, twice a day and twice every 2 days were significantly higher than those of the fish fed once a day or once every 2 days （P〈0.05）, but feed efficiency ratios in the fish fed once a day, twice every 2 days and once every 2 days were significantly higher than those of the fish fed triple a day or twice a day （P〈0.05）. As feeding frequency gradually decreased, moisture content of fish body increased. Feeding frequency had no significant effects on protein and fat content of fish body, except for fish fed once every 2 days. Hepatosomatic indices （HIS） of fish with different feeding frequencies were not significantly different and the livers were normal. It is concluded that two meals every 2 days is more effective than other feeding frequencies for improving growth performance of juvenile Darkbarbel catfish from 5.9 to 31.8g. Gastric evacuation is a simple and convenient way to evaluate optimal feeding frequency of juvenile Darkbarbel catfish.%应用鱼类胃排空与养殖实验方法，研究了瓦氏黄颡鱼幼鱼的不同投饲频率对其胃排空、生长以及体组成的影响。结果表明，瓦氏黄颡鱼其胃排空的最佳数学模型描述为平方根模型，胃内饲料在投喂后36h和40h左右完全排空，达到投喂前水平。瓦氏黄颡鱼幼鱼在投饲频率为1天3次、1天2次和2天2次时其生长率和摄食量显著高于投饲频率为1天1次或2天1次时（P〈0．05）；而在投饲频率为1天1次、2天2次和2天1次时其饲料效益率显著高于投饲频率为1天3次或1天2次时（P〈0．05）。随着投饲频率降低，投饲频率对鱼体营养成分均无明显影响（P〉0．05）。各投饲频率组间的肝体指数无显著性差异，肝脏结构正常。5．9—31．8g瓦氏黄颡鱼幼鱼的最佳投饲频率为2天2次，它较1天1次和2天1次明显提高了生长速度，较1天3次、1天2次明显提高了饲料效益。
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