摘要：
The aim of the study was to investigate the effects of nutritional modes on the specific growth rate, nutrients and histology of muscle and hepatopancreas of grass carp. A total 270 of grass carp ( Ctenopharyng?odon idellus) with the similar body weight was divided into 3 groups with 3 replicates per group and 30 fish per replicate and fed under three nutritional modes ( Pennisetum purpereum, 20% Pennisetum purpereum+80%compound feed, compound feed, dry sample base) , respectively. The experiment lasted for 180 d. Results showed as follows: 1) under Pennisetum purpereum mode, the specific growth rate and ether extract content in abdominal muscle, dorsal muscle and hepatopancreas were significantly lower than those under other nutritional modes ( P＜0.05) , while the feed conversion efficiency and crude protein content in the above tissues and Ca in abdominal muscle and dorsal muscle were significantly higher than those under other nutritional modes ( P＜0.05). Fat vacuole in hepatocytes was not visible. Both intermuscular and intramuscular fat were less. Muscle fibers were thinner but tightly arranged. 2) Under mixed mode, except for the lowest nitrogen?free extract con?tent in abdominal muscle and the highest Cu, Zn, Fe contents in abdominal muscle and Ca and Mn contents in the hepatopancreas, other determined nutrients in the three kinds of tissues, as well as the specific growth rate, feed conversion efficiency, muscle fiber diameter and interspace, intermuscular and intramuscular fat, and fat vacuoles in hepatocytes were all between other two nutritional modes.3) Under compound feed mode, the spe?cific growth rate, nitrogen?free extract in hepatopancreas, ether extract and ash contents in abdominal muscle, dorsal muscle and hepatopancreas of grass carp were significantly higher than those under other two nutritional modes( P＜0.05) , but the feed conversion efficiency, nitrogen?free extract content in dorsal muscle, crude pro?tein content in three kinds of tissues, as well as Zn, Mg and Fe contents in abdominal muscle, and Zn, Cu, Mg and Fe contents in hepatopancreas were significantly lower than those under other two modes ( P＜0.05). In addition, fat vacuoles in hepatocytes, intermuscular and intramuscular fat, diameter and interspace of muscle fibers all obviously increased. On the whole, the 20% Pennisetum purpereum+80% compound feed mixed mode is better than the other two modes for the grass carp.[ Chinese Journal of Animal Nutrition, 2019, 31 (6) :2898?2906]%本试验旨在研究营养模式对草鱼特定生长率、肌肉及肝胰脏营养成分与组织结构的影响.选取270尾体质量相近的草鱼,随机分为3组,每组3个重复,每个重复30尾鱼,分别采用矮象草( Pennisetum purpereum) 、20%矮象草+80%配合饲料混合、配合饲料(均以干重计) 3种营养模式进行饲喂.试验期为180 d.结果表明:1)矮象草模式下,草鱼特定生长率及腹肌、背肌、肝胰脏中粗脂肪含量均显著低于其他2种营养模式( P＜0.05) ,但饲料系数及3种组织中粗蛋白质含量以及腹肌和背肌中钙( Ca)含量则显著高于其他2种营养模式( P＜0.05) ,且肝细胞内无明显脂肪空泡,肌间和肌内脂肪较少,肌纤维较细且排列紧密. 2)混合模式下,草鱼除腹肌无氮浸出物含量最低,腹肌铜( Cu) ,背肌锌( Zn) 、铁( Fe)及肝胰脏Ca、锰( Mn)含量显著高于其他2种营养模式( P＜0.05)外,特定生长率、饲料系数、肌纤维直径及间隙、肌间与肌内脂肪、肝细胞中脂肪空泡数量均介于矮象草模式和配合饲料模式之间. 3)配合饲料模式下,草鱼特定生长率、肝胰脏无氮浸出物和3 种组织中粗脂肪、粗灰分含量均显著高于其他2 种营养模式(P＜0.05) ;但饲料系数,背肌无氮浸出物含量,腹肌Zn、镁( Mg) 、Fe含量,肝胰脏Zn、Cu、Mg、Fe含量以及3种组织中粗蛋白质含量均显著低于其他2种营养模式( P＜0.05) ,且肝细胞内脂肪空泡数量、肌间和肌内脂肪沉积量、肌纤维直径、肌纤维间隙等均明显增加.综合来看,草鱼的营养模式以20%矮象草+80%配合饲料混合模式为宜.
