青贮甘蔗梢替代玉米秸秆对湖羊生长性能、消化代谢及肉品质的影响

Effects of replacing corn straw silage with sugarcane tip silage on growth performance,digestion and metabolism and meat quality of Hu sheep

[目的]本试验旨在探索青贮甘蔗梢替代青贮玉米秸秆作为肉羊日粮的可行性,并确定最佳的替代比例。[方法]选取3月龄、体重相近[(20.15±2.18)kg]的健康湖羊公羔48只,随机分成4组,每组3个重复,分别用青贮甘蔗梢替代0%(对照组)、50%(A组)、75%(B组)、100%(C组)青贮玉米秸秆饲喂,预试期10 d,正试期为60 d。试验开始和结束时测定湖羊生产性能,并采集血液样品进行血清生化分析;饲喂试验结束后,从每组不同重复各选择1只湖羊屠宰,测定其屠宰性能及肉品质;从每组不同重复再挑选3只湖羊进行消化代谢试验,测定养分消化代谢参数。[结果]B组和C组平均日增重、胴体重和屠宰率显著高于A组和对照组(P<0.05);B组和C组氮沉积量显著高于A组和对照组,A组、B组和C组的表观消化能和能量转化率均显著高于对照组;各组间血液生化指标、肉品质及肉营养成分均无显著差异(P>0.05)。青贮甘蔗梢替代75%和100%青贮玉米秸秆可以显著提高湖羊生长性能和屠宰性能,而且对湖羊血清生化指标、组织器官发育和肉品质无不利影响。[结论]青贮甘蔗梢可替代青贮玉米秸秆饲喂肉羊,且最佳替代比例为75%~100%。

[Objectives]The purpose of the trial was to explore the feasibility of using sugarcane tip silage to replace corn straw silage in diets of mutton sheep,and to evaluate the optimal replacement ration.[Methods]Forty-eight healthy male Hu sheep with similar body weight[(20.15±2.18)kg]were randomly divided into four groups,and each group had 3 replicates.Fed diets containing 0%(control),50%(A group),75%(B group),and 100%(C group)sugarcane tip silage replaced the corn straw silage.The experiment lasted for 60 d,including 10 d adapting period.The growth performance were determined at the beginning and end of the experiment,and blood sample were collected for serum biochemical analysis.One sheep was selected from each group and 3 sheep were killed to measure slaughter performance and meat quality after the feeding trial.Three sheep of each group were selected for digestion and metabolism tests to determine digestion and metabolism test parameters.[Results]The average daily gain,carcass weight and slaughter rate in B group and C group were significantly higher than those of A group and control group(P<0.05).The nitrogen deposition in B group and C group were significantly higher than those of A group and control group(P<0.05).Compared with the control group,the apparent digestibility and energy conversion efficiency of group A,B and C significantly increased.There were no treatment differences in blood biochemical parameters,meat quality and nutritional composition of meat(P>0.05).Using sugarcane tip silage of 75% and 100% to replace corn straw silage significantly improved the growth performance and slaughter performance of Hu sheep,and had no effect on serum biochemical indexes,tissue and organ development and meat quality of Hu sheep.[Conclusions]Sugarcane tip silage can replace corn straw silage to feed sheep,and the optimal replacement rate was 75%-100%.