壳聚糖对异育银鲫生长和饲料消化率的影响

Effect of Chitosan on Growth and Dietary Digestibility of Carassius auratus gibelio

采用单因子试验设计方法,试验分成4组进行,对照组和3个试验组,每组3个重复.对照组投喂基础饲料,3个试验组分别投喂在基础饲料中添加0.25%壳聚糖、0.50%壳聚糖和1.00%壳聚糖的试验饲料,自然水温下饲养异育银鲫Carassius auratus gibelio 50尾/池[初始体质量为(78.31±2.15)g].64 d后,采用国标常规方法测定异育银鲫肌肉的营养成分,采用国标间接法(以Cr2O3为外源指示剂)测定饲料能量和营养成分消化率,并计算特定生长率、饲料系数、蛋白质效率、蛋白质沉积率、白肌RNA/DNA,旨在探讨壳聚糖对异育银鲫生长、饲料营养成分和能量消化率及利用率的影响.结果表明,饲料中添加0.50%以上的壳聚糖可以显著提高异育银鲫的特定生长率(P<0.05)、蛋白质消化率(P<0.05)和白肌RNA/DNA(P<0.05),显著降低异育银鲫对饲料脂肪的消化率(P<0.05).添加0.50%壳聚糖可以显著降低异育银鲫的饲料系数(P<0.05),显著提高蛋白质效率和肌肉中的蛋白质沉积率(P<0.05),显著提高异育银鲫对饲料能量的消化率(P<0.05).添加0.25%和0.50%壳聚糖可以显著提高鱼体肌肉中的灰分含量(P<0.05).由此看来,在饲料中添加0.50%壳聚糖可以提高蛋白质和能量的消化率和利用率,从而降低饲料系数、促进异育银鲫的生长.

The trial was divided into one control group and three tested ones.Each group was in triaplicate.Gibel carp,Carassius auratus gibelio[initial mass of（78.31±2.15） g] with fifty for every pond were fed with control diet in control group and tested ones were control diet with chitosan of 0.25%,0.50% and 1.00% in three tested groups below indoor temperature respectively.Muscle components were determined with national standard Method.The digestibilities of the dietary general energy and nutriment were determined by the indirect way of external indicator Cr2O3 and the survive ratio,the specific growth rate（SGR）,the feed coefficient,the protein efficiency,protein retention,RNA/DNA ratio in white muscle were measured in order to investigate influence of the chitosan on the digestibilities and the utilization of the dietary nutriments and general energy of gibel carp after 64 d feeding period.Results showed that the supplement with 0.50% or more chitosan could improve the SGR,protein digestibility,the RNA/DNA ratio in white muscle（P0.05） and decrease the fat digestibility of gibel carp respectively（P0.05）.The supplement with 0.50% chitosan could improve the protein efficiency,protein retention and the digestibility of the dietary general energy（P0.05） and decrease the feed coefficient of the fish respectively（P0.05）.The supplement with 0.25% and 0.50% chitosan could improve ash content in muscle（P0.05）.Therefore,the supplement with 0.50% chitosan in gibel carp diet could improve the growth and the digestibilities of the dietary nutriments and general energy and decrease the feed coefficient of gibel carp.