不同活体饵料对斑马鱼幼鱼发育的影响

The effects of different live diets on the development of the zebrafish larvae

目的:探究不同活体饵料对斑马鱼幼鱼生长发育的影响,筛选适宜斑马鱼幼体生长的饵料及投喂方式。方法:挑选5 dpf活泼健康的野生型(AB)斑马鱼幼鱼,随机分为饥饿组、草履虫组、轮虫组、丰年虫组、草履虫+轮虫组、草履虫+丰年虫组和轮虫+丰年虫组。每日记录幼鱼存活率和摄食丰年虫幼鱼比例,每隔10天拍照并测量幼鱼体长,40天后测量幼鱼最终体长和体质量。结果:在斑马鱼幼鱼发育早期,草履虫各组均保持较高存活率,轮虫组和轮虫+丰年虫组幼鱼死亡率较高:随着幼鱼发育,所有添加丰年虫的实验组包括单独投喂丰年虫组最终存活率都高于未添加组,并且幼体体质量和体长也显著高于未投喂丰年虫组。斑马鱼幼鱼只有发育到9 dpf后才能摄食丰年虫,混合投喂草履虫有助于提高幼鱼丰年虫摄食率,直至13 dpf各组幼鱼摄食丰年虫。10 dpf前所有投喂草履虫的幼鱼生长速度显著高于未投喂草履虫组,但10 dpf后投喂丰年虫所有实验组幼鱼体长增速显著增加,未投喂丰年虫的3个实验组中幼鱼生长速度显著减慢。结论:在实验室斑马鱼幼鱼饲养中轮虫不适合作为斑马鱼幼鱼的饵料,草履虫是斑马鱼幼鱼早期适宜的饵料,后期适宜饵料为丰年虫,最佳方式为9 dpf前投喂草履虫,从9 dpf开始添加丰年虫,13 dpf后完全由丰年虫替代草履虫。

Objective:To investigate the effects of different live diets on the development of zebrafish larvae,and screen suitable diet and feeding manner for zebrafish growth.Methods:All zebrafish larvae were divided into 7 groups,including Starvation group,Paramecium group,Rotifer group,Artemia group,Paramecium+Rotifer group,Paramecium+Artemia group,and Rotifer+Artemia group.Survival rates and the rates of the zebrafish larvae that ingested Artemia were recorded every day.Meanwhile,the body lengths of the zebrafish were measured in every ten days.The observation was terminated at 40 dpf(day post fertilization)and the final weight and body length of the fish were measured respectively.Results:During the early development stage of the zebrafish larvae,all the fish that fed with the paramecium had higher survival rates,while the fish in the Rotifera group and Rotifera+Artemia group had high mortalities.However,with the development of the zebrafish,the survival rate,final weight and body length of all groups that fed with artemia,even the group fed with only artemia,were all significantly higher than the groups without artemia.In addition,the zebrafish larvae could ingest the artemia only when they developed to 9 dpf and adding paramecium could increase the rate of the zebrafish larvae that ingest artemia until 13 dpf when all the zebrafish larvae ate the artemia.Moreover,the results of the body length showed that the growth rate of fish in all the groups that fed with paramecium were higher than that without paramecium before 10 dpf.However,after 10 dpf the growth rates of all the groups that fed with artemia were remarkably increased.Conclusion:Our results indicate that rotifers are not suitable for zebrafish larvae.The paramecium is the optimal diet for zebrafish at the early stage,while artemia could substitute the paramecium to provide more nutrition for the fish at the late stage.Therefore,the best feeding way for zebrafish larvae in the lab is that before 9 dpf only feeding paramecium and adding artemia at 10 dpf and then were totally replaced at 13 dpf.Our results could provide instructive guidance for the zebrafish culturing and diet selection.