Effects of Dietary Carbohydrate-lipid Ratio on Growth, Body Composition and Digestive Enzyme Activities of Juvenile Peanut Worm,Sipunculus nudus

[Objective] This study was conducted to investigate the effects of dietary carbohydrate-lipid( C / L) ratios on growth performance,body composition and digestive enzyme activities of juvenile peanut worm. [Methods]Juvenile peanut worm with average body weight of( 16. 77 ± 0. 40) mg were fed with five isonitrogenous and isoenergetic diets formulated to contain different carbohydrate / lipid( C / L) ratios( 0. 68,1. 02,1. 62,2. 61 or 4. 35) for 8 weeks. [Results] The dietary C / L ratios had no significant effects on survival of juvenile peanut worm( P 】 0. 05). With the increasing of dietary C / L ratios,weight growth rate( WGR)and specific growth rate( SGR) increased when dietary C / L ratios were between 0. 68 and 2. 61,and then decreased significantly with dietary C / L ratio further increased. When the dietary C / L ratio was 2. 61( carbohydrate level was 20. 64%,lipid level was 7. 92%) both WGR and SGR produced the maximum value,they were 451. 78 ± 16. 85% and 3. 41 ± 0. 06 % / d,respectively. The dietary C / L ratios had significant effects on body moisture,body protein content and body lipid content( P 【 0. 05),but no significant effects on body ash content of juvenile peanut worm( P 】 0. 05). Different C / L ratios had significant effects on amylase activity and lipases activity of juvenile peanut worm( P 【 0. 05),but no significant effects on protease activity( P 】 0. 05). [Conclusion]The regression model analysis showed that the most suitable dietary C / L ratio which can make juvenile peanut worm acquire the best weight growth rate is 2. 42.

[Objective] This study was conducted to investigate the effects of dietary carbohydrate-lipid( C / L) ratios on growth performance,body composition and digestive enzyme activities of juvenile peanut worm. [Methods]Juvenile peanut worm with average body weight of( 16. 77 ± 0. 40) mg were fed with five isonitrogenous and isoenergetic diets formulated to contain different carbohydrate / lipid( C / L) ratios( 0. 68,1. 02,1. 62,2. 61 or 4. 35) for 8 weeks. [Results] The dietary C / L ratios had no significant effects on survival of juvenile peanut worm( P > 0. 05). With the increasing of dietary C / L ratios,weight growth rate( WGR)and specific growth rate( SGR) increased when dietary C / L ratios were between 0. 68 and 2. 61,and then decreased significantly with dietary C / L ratio further increased. When the dietary C / L ratio was 2. 61( carbohydrate level was 20. 64%,lipid level was 7. 92%) both WGR and SGR produced the maximum value,they were 451. 78 ± 16. 85% and 3. 41 ± 0. 06 % / d,respectively. The dietary C / L ratios had significant effects on body moisture,body protein content and body lipid content( P < 0. 05),but no significant effects on body ash content of juvenile peanut worm( P > 0. 05). Different C / L ratios had significant effects on amylase activity and lipases activity of juvenile peanut worm( P < 0. 05),but no significant effects on protease activity( P > 0. 05). [Conclusion]The regression model analysis showed that the most suitable dietary C / L ratio which can make juvenile peanut worm acquire the best weight growth rate is 2. 42.