饲料铜水平对方格星虫稚虫生长及体组成的影响

【目的】了解饲料中微量元素铜水平对方格星虫(Sipunculus nudus Linnaeus)稚虫生长及体组成的影响,探索饲料中铜元素的最佳含量。【方法】通过给方格星虫稚虫投喂不同铜水平(2.7 mg/kg,7.5 mg/kg,11.2mg/kg,19.8mg/kg,30.4mg/kg,52.1mg/kg)的饲料56d,研究微量元素铜对方格星虫的成活率、增重率(Weight gain rate,WGR)、特定生长率(Specific gain rate,SGR)、体组成成分的影响。【结果】饲料中的微量元素铜水平对方格星虫稚虫的增重率、特定生长率有显著影响(P0.05)。随着饲料中铜含量的提高,方格星虫稚虫的SGR和WGR都呈先上升后下降,之后再上升的趋势,当饲料铜含量为11.2mg/kg时,方格星虫稚虫增重率和特定生长率均达到最大值。饲料铜水平对方格星虫稚虫的成活率、体组成成分没有显著影响(P0.05)。【结论】基础饲料中铜的适宜添加量为7.5~11.2mg/kg。

Effect of Dietary Copper Level on Growth Performance and Body Composition of Juvenile Peanut Worm, Sipunculus nudus Linnaeus

Objective]This trial was conducted to investigate the effects of dietary copper lev-els on growth performance and body composition of j uvenile peanut worm,Sipunculus nudus Linnaeus.Methods]S.nudus juveniles with average body weight of (18.45 ±0.11) mg were fed diets with six copper levels (2.7 mg/kg,7.5 mg/kg,11.2 mg/kg,19.8 mg/kg, 30.4 mg/kg,52.1 mg/kg diet)for 56 d.Results]The results showed that the dietary copper levels had significant effects on weight gain rate (WGR),specific gain rate (SGR)(P <0.05).With the increasing of dietary copper levels,WGR and SGR were increased,then de-creased in generally,and increased again,and reached the maximum at 1 1 .2 mg/kg.No significant differences were observed in survival ratio (SR),body moisture,body protein content, body lipid content and body ash content of S. nudus among dietary treatments with graded levels of copper (P >0.05 ).Conclusion]The dietary copper levels range which could acquire high WGR were from 7.5 mg/kg to 11.2 mg/kg.