发酵木薯渣替代部分玉米对湖羊生长性能、血清生化指标、屠宰性能和肉品质的影响

本研究旨在探索发酵木薯渣在湖羊日粮中替代部分能量饲料(玉米)的可行性,并确定最佳替代比例。选择48只体重为(18.35±1.39) kg的湖羊公羔,随机分成4组,每组4个重复,每个重复3只羊,分别用发酵木薯渣替代0%(对照组)、20%(A组)、40%(B组)、60%(C组)玉米的日粮进行饲喂,试验期60 d。在试验开始和结束时测定羔羊生长性能,并采集血液样品进行分析,同时在试验结束时进行屠宰试验,测定屠宰性能以及肉品质。研究结果表明,A组湖羊的平均采食量(ADFI)显著高于对照组和B组(P<0.05),日增重(ADG)的变化趋势为A组>B组>对照组(P>0.05),A组和B组的料重比(F/G)有低于对照组的趋势(P>0.05)。而C组湖羊由于腹泻严重,于试验开始2周后将其淘汰。A组的宰前活重、胴体重、肝、瓣胃和肾的重量显著大于对照组和B组(P<0.05),而各组其他内脏器官无显著差异(P>0.05)。各组湖羊的血液生化指标和肉品质均无显著差异(P>0.05)。B组的肉豆蔻酸、棕榈酸等饱和脂肪酸的含量显著低于A组(P<0.05),而B组的十七烷酸和花生酸的含量显著高于A组和对照组(P<0.05),其他种类的脂肪酸无显著差异(P>0.05)。由此可见,利用发酵木薯渣替代20%玉米对湖羊公羔的生长发育和健康无不良影响,且能降低饲料成本,育肥效果最好。因此,将发酵木薯渣作为湖羊的饲料来源是完全可行的。

Effects of substitution of corn and fermented cassava residue in the diet on growth,carcass characteristics and meat quality of Hu lamb

To evaluate the optimal replacement ratio of energy source (mainly corn) with fermented cassava residue in diets of Hu lambs at 3 months of age 48 Hu lambs [(18.4±1.4) kg liveweight] were randomly divided into four groups with 4 replicates (3 lambs in each replicate),and fed diets containing 0 (control),20％ (A group),40％ (B group),and 60％ (C group) fermented cassava residue in place of the normal diet of corn.The experiment lasted for 60 d.Growth and blood biochemical indices were determined after feeding for 60days;four lambs of each group were killed to measure slaughter performance and meat quality.Lambs in group C were removed from the trial after 2 weeks due to animal health problems.The results showed that the average daily feed intake of lambs in A group was significantly higher than that of B group and the control (P＜0.05).Both A and B group lambs had improved feed:liveweight gain ratios compared with the control group (P＞0.05).Liveweight,carcass weight and the weight of the liver,abomasum and kidney's in A group were significantly higher than the control and B group (P＜0.05).There were no treatment differences (P＞0.05)in blood serum biochemical indices and meat quality.Saturated fatty acids,including myristic acid and palmitic acid in B group lambs were significantly lower than in A group;heptadecanoic acid and arachidic acid in B group lambs were significantly higher than A group and control lambs (P＜0.05).The optimal replacement rate of corn with fermented cassava residue in Hu lamb's diet was 20％,a substitution rate which is feasible based on feed costs.