禁食处理对尼罗罗非鱼体重及肌肉营养成分的影响

Effects of Starvation Stress on the Body Weight and Muscle Nutrition Composition of Nile Tilapia

获得罗非鱼最佳的饥饿胁迫时间,兼顾鱼的品质与经济效益,旨在为罗非鱼品质调控提供参考。以达到上市规格(837.78±86.78) g的尼罗罗非鱼为研究对象,分析罗非鱼在禁食后的不同时期内其体重以及肌肉营养成分的变化。结果表明,随着饥饿时间的增加,尼罗罗非鱼的体重持续减少。试验结束时体重减少14.35%,肥满度为3.16~3.52,肝体比呈先升后降趋势,胃体比及肠体比随时间推移逐渐降低,肌肉蛋白质、脂肪含量降低,而灰分、水分等增加;肌肉中EAA/NEAA比例高于60%,脂肪酸及微量元素呈动态变化。根据鱼体减重和损耗,结合肌肉中营养成分及微量元素等的变化,综合成本、口感等,罗非鱼禁食14~21 d较为适宜。

The purpose of this study is to obtain the optimal time of starvation stress for tilapia,and to provide reference for quality control of tilapia by considering both fish quality and economic benefits.The changes of body weight and muscle nutrition composition of Nile tilapia(837.78±86.78) g in different periods after fasting were analyzed.The results showed that the body weight of Nile tilapia decreased continuously with the increase of starvation time.At the end of the experiment(28 day post-starvation),the condition factor was 3.16 to 3.52,the body weight decreased by 14.35%,the liver-somatic index increased first and then decreased,the stomach-body ratio and viserosomatic index decreased gradually with time,the content of crude protein and fat in muscle decreased while the ash and moisture increased.In addition,the EAA/NEAA ratio in muscle was higher than 60%,and the content of fatty acids and trace elements showed dynamic changes.In conclusion,it is suitable for tilapia to fast for 14 to 21d according to the changes of body weight,mortality,and nutritional component and trace elements in muscle,as well as the taste and economic benefits.