低蛋白质水平饲粮添加不同水平赖氨酸对肥育猪生长性能、胴体性状、肉品质及氮排放的影响

Effects of Different Supplemental Levels of Lysine in Low Protein Diets on Performance,Carcass Traits,Meat Quality and Nitrogen Excretion of Finishing Pigs

本试验旨在研究低蛋白质水平饲粮添加不同水平赖氨酸对肥育猪生长性能、胴体性状、肉品质及氮排放的影响。试验1:选取健康、初始体重[(78.19±6.69)kg]相近的“杜×长×大”肥育猪108头,随机分为6组,每组6个重复,每个重复3头猪。组1为正常蛋白质水平饲粮组,即12.5%粗蛋白质(CP)+0.73%标准回肠可消化赖氨酸(SID-Lys);组2、3、4、5和6为低蛋白质水平饲粮(10.5%CP)不同SID-Lys组,SID-Lys水平分别为0.58%、0.66%、0.73%、0.80%和0.88%。试验期28 d。试验2:选取初始体重为(90.56±3.28)kg的“杜×长×大”肥育猪18头,随机分为3组,每组6个重复,每个重复1头猪。3组分别饲喂试验1中组1、4和5的饲粮,试验期共7 d,其中预试期3 d,氮平衡试验期4 d。结果表明:1)降低饲粮蛋白质水平对肥育猪的生长性能无显著影响(P>0.05)。低蛋白质水平饲粮添加不同水平赖氨酸对肥育猪的生长性能无显著影响(P>0.05)。2)降低饲粮蛋白质水平对肥育猪胴体性状无显著影响(P>0.05),但显著影响肥育猪背最长肌的红度值(P<0.05)。低蛋白质水平饲粮添加不同水平赖氨酸对肥育猪胴体性状无显著影响(P>0.05),但显著影响肥育猪背最长肌的滴水损失(P<0.05)。3)降低饲粮蛋白质水平显著影响了肥育猪的粪氮排放、尿氮排放和总氮排放(P<0.05)。低蛋白质水平饲粮添加不同水平赖氨酸对肥育猪粪氮排放、尿氮排放和总氮排放均无显著影响(P>0.05)。由此可见,降低饲粮蛋白质水平对肥育猪的生长性能和胴体性状无显著影响,且可改善肉色,降低总氮排放;低蛋白质水平饲粮添加不同水平赖氨酸对肥育猪生长性能、胴体性状和氮排放无显著影响,但可改善肉品质。

This study was conducted to investigate the effect of different supplemental levels of lysine in low protein diets on performance,carcass traits,meat quality and nitrogen excretion of finishing pigs.In experiment 1,a total of 108 healthy“Durco×Landrace×Large White”finishing pigs with average initial body weight of(78.19±6.69)kg were assigned into 6 groups with 6 replicates per group and 3 pigs per replicate.Group 1 was normal protein level diet group,which was 12.5%crude protein(CP)and 0.73%standardized ileal digestible lysine(SID-Lys);groups 2,3,4,5 and 6 were low protein level diet(10.5%CP)and different SID-Lys groups with the SID-Lys levels were 0.58%,0.66%,0.73%,0.80%and 0.88%,respectively.The experiment lasted for 28 days.In experiment 2,eighteen“Durco×Landrace×Large White”finishing pigs with average initial body weight of(90.56±3.28)kg were assigned into 3 groups with 6 replicates per group and 1 pig per replicate.Pigs in the 3 groups were fed the same diets of groups 1,4 and 5 in experiment 1,respectively.The experiment lasted for 7 days include 3 days preliminary experiment period and 4 days nitrogen balance experiment period.The results showed as follows:1)reducing dietary protein level had no significant effects on growth performance of finishing pigs(P>0.05).Different supplemental levels of lysine in low protein diets had no significant effects on growth performance of finishing pigs(P>0.05).2)Reducing dietary protein level had no significant effects on carcass traits of finishing pigs(P>0.05),but significant affected the Longissimus dorsi redness value of finishing pigs(P<0.05).Different supplemental levels of lysine in low protein diets had no significant effects on carcass traits of finishing pigs(P>0.05),but significant affected the Longissimus dorsi drip loss of finishing pigs(P<0.05).3)Reducing dietary protein level significant affected the fecal nitrogen excretion,urine nitrogen excretion and total nitrogen excretion of finishing pigs(P<0.05).Different supplemental levels of lysine in low protein diets had no significant effects on fecal nitrogen excretion,urine nitrogen excretion and total nitrogen excretion of finishing pigs(P>0.05).Collectively,reducing dietary protein level have no significant effects on growth performance and carcass traits of finishing pigs,but improve the meat color and decrease the nitrogen excretion.Different supplemental levels of lysine in low protein diets have no significant effects on growth performance,carcass traits and nitrogen excretion of finishing pigs,but improve the meat quality.