胍基乙酸对不同蛋白水平日粮猪能量和氮沉积的影响

Effects of Guanidinoacetic Acid on Energy Deposition in Pigs Fed the Different Protein-Levels Diets

本研究旨在探究高蛋白和低蛋白日粮中添加不同水平的胍基乙酸对生长猪氮平衡、蛋白质沉积、脂肪沉积和日粮有效能值的影响。试验一和试验二均采用完全随机区组设计,每个试验将18头试验猪分为3组,分别饲喂添加水平为0、300、1200 mg/kg胍基乙酸的高蛋白(平均值18.6%,干物质基础)和低蛋白(平均值15.2%,干物质基础)日粮。试验一和试验二中每个日粮处理组包含6个重复,每个重复1头猪。每个试验共20 d,7 d为代谢笼适应期,随后7 d为日粮适应期,1 d为呼吸测热室适应期,5 d为粪尿收集期。结果表明:高蛋白日粮中添加300 mg/kg和1200 mg/kg胍基乙酸不影响生长猪日粮的净能值和呼吸熵,但提高了尿氮的排出量和日粮的脂肪沉积(P<0.05);低蛋白日粮中添加300 mg/kg和1200 mg/kg胍基乙酸不影响生长猪的呼吸熵,但提高了日粮的蛋白质沉积和净能/代谢能,并且降低了尿氮的排出量以及日粮脂肪的沉积(P<0.05);高蛋白日粮中添加300 mg/kg和1200 mg/kg胍基乙酸降低了氮的利用率,但是低蛋白日粮中添加相同水平的胍基乙酸提高了氮的利用率(P<0.05)。综上,日粮中添加不同水平的胍基乙酸对生长猪能量平衡和氮平衡的作用受日粮蛋白质水平的影响。基于本研究结果,低蛋白生长猪日粮中添加1200 mg/kg胍基乙酸可以提高日粮氮的沉积和能量利用效率,进而提高养猪生产的高效性。

The aim of this study was to explore effects of different levels of guanidinoacetic acid supplemented into highprotein and low-protein diets to growing pigs on dietary nitrogen balance,protein deposition,fat deposition and available energy.A total of 18 growing pigs in each experiment were allocated into 3 groups to be fed high-protein(average crude protein level of 18.6%as dry matter basis)and low-protein(average crude protein level of 15.2%as dry matter basis)diets containing 0 mg/kg,300 mg/kg and 1200 mg/kg guanidinoacetic acid in experimental 1 and 2,respectively.In experiment 1 and 2,each dietary treatment included 6 replicates and 1 pig per replicate.Each experiment lasted 20 d,including 7 d of metabolic cages adaptation,subsequent 7 d of diet adaptation,1 d of respiration chamber adaptation and 5 d of total urine and feces collection.The results showed 300 mg/kg and 1200 mg/kg of guanidinoacetic acid added into the high-protein diets did not affect net energy in diets and respiratory quotient in growing pigs,but improved the urine nitrogen output and dietary fat deposition(P<0.05).However,300 mg/kg and 1200 mg/kg of guanidinoacetic acid added into the low-protein diets did not affect respiratory quotient in growing pigs,but improved dietary protein deposition and a ratio of net energy to metabolizable energy,and decreased the urine nitrogen output and dietary fat deposition(P<0.05).The high-protein diets supplemented with 300 mg/kg and 1200 mg/kg of guanidinoacetic acid decreased nitrogen utilization,but the low-protein diets supplied with the same levels of guanidinoacetic acid increased nitrogen utilization of pigs(P<0.05).In summary,the role of different guanidinoacetic acid levels added into the diets would be influenced by dietary protein levels.Based on the results in the current study,a moderate inclusion level of guanidinoacetic acid should be added into a low-protein diets to improve protein deposition and dietary net energy,resulting in high efficiency of pig production.