桑叶对罗非鱼生长性能、脂质代谢和肌肉品质的影响

Effects of Dietary Mulberry Leaves on Growth Performance,Fat Metabolism and Muscle Quality of Tilapia( Oreochromis niloticus)

试验选取云南、陕西、重庆所产桑叶,在基础饲料中分别添加0(对照组)、5%、10%不同来源桑叶粉,配制成7种等能等氮的试验饲料,在室内淡水循环养殖系统中饲喂平均体重为9 g的吉富罗非鱼8周,以研究桑叶对罗非鱼生长性能、脂质代谢和肌肉品质的影响。每组设3个重复,每个重复40尾鱼。结果表明:桑叶来源、添加水平以及二者的交互作用对罗非鱼的末重、特定生长率(SGR)、蛋白质效率(PER)、饲料系数(FCR)和摄食率(FR)均无显著影响(P>0.05)。各试验组罗非鱼的脏体指数(VSI)、肝体指数(HSI)以及血清中总胆固醇(CHO)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)含量均显著低于对照组(P<0.05),且随桑叶添加水平的增加上述指标有不同程度地降低(P>0.05或P<0.05)。对于不同来源的桑叶,均表现为10%组罗非鱼的血清高密度脂蛋白胆固醇(HDL-C)含量及HDL-C/CHO和HDL-C/LDL-C最高,肌肉p H降低值、滴水损失和全血葡萄糖含量最低,且与对照组和5%组的差异达到显著水平(P<0.05)。各组罗非鱼的肥满度(CF),鱼体水分、粗蛋白质、粗脂肪、粗灰分含量以及肌肉熟肉率无显著差异(P>0.05)。由此可见,饲料中添加10%的桑叶不会影响罗非鱼的生长性能,同时可有效调节罗非鱼的脂质代谢,改善其肌肉品质。

In order to study effects of dietary mulberry leaves on growth performance,fat metabolism and muscle quality of tilapia（ Oreochromis niloticus）,3 mulberry leaves were collected from Yunnan,Shaanxi and Chongqin. A basal diet was supplemented with 0（ control group）,5% and 10% mulberry leaf powder from different sources to formulate 7 isonitrogenous and isoenergetic experimental diets. Genetically improved farmed tilapia（ GIFT） with the average body weight of 9 g were used as experimental animal,and were randomly divided into 7 groups with 3 replicates per group and 40 fish per replicate. Fish in each group were fed one experimental diet for 8 weeks in a recirculated filtered rearing system. The results showed as follows： source and supplemental level of mulberry leaves and their interaction had no significant differences in final body weight,specific growth rate（ SGR）,protein efficiency ratio（ PER）,feed conversion ratio（ FCR） and feeding rate（ FR）（ P0.05）. The viscerosomatic index（ VSI）,hepatosomatic index（ HSI） and the contents of total cholesterol（ CHO）,triglyceride（ TG） and lowdensity lipopretein cholestorol（ LDL-C） in experimental groups were significantly lower than those in control group（ P〈 0.05）,and those indices had different degrees of decrease with the supplemental level of mulberry leaves increasing（ P〉 0. 05 or P〈 0. 05）. For mulberry leaves from different sources,the fish in the 10% group all had the highest values of serum high density lipoprotein cholesterol（ HDL-C） content,HDL-C / CHO and HDL-C / LDL-C and the lowest values of muscle p H decreased value,drop loss and blood glucose content,and the differences in those indices reached significance level between 10% group and control group and 5% group（ P〈 0.05）. There were no significant differences in condition factor（ CF）,the contents of moisture,crude protein,crude lipid and crude ash in whole body,and the muscle cooking rate among all groups（ P〉 0.05）. The results suggest that dietary mulberry leaves can not affect the growth performance of tilapia,but can effectively regulate the fat metabolism and improve the muscle quality of tilapia.