本试验旨在研究饲粮添加一水肌酸 (CMH) 及其组合添加物对生长育肥猪胴体组成、肉质性状及代谢分子指标的影响, 为进一步完善CMH在肉质营养调控中的应用提供参考.选择60～70 kg体重"杜×大×长"阉公猪100头, 随机分为5组 (每组20个重复, 每个重复1头猪) , 分别饲喂基础饲粮 (对照组) 、CMH饲粮 (在基础饲粮中添加0.5 g/kg的CMH) 、CMH+α-硫辛酸 (ALA) 饲粮 (在基础饲粮中添加0.5 g/kg的CMH和0.1 g/kg的ALA) 、CMH+牛磺酸 (Tau) 饲粮 (在基础饲粮中添加0.5 g/kg的CMH和0.1 g/kg的Tau) 和CMH+L-苹果酸 (LMA) 饲粮 (在基础饲粮中添加0.5 g/kg的CMH和0.5 g/kg的LMA) , 饲养50 d后统一屠宰, 采集样品并测定指标.结果表明:与对照组相比, 饲粮添加CMH及其不同组合添加物均显著降低生长育肥猪背膘厚度 (P<0.05) , 有提高背最长肌水分和降低脂肪含量的趋势 (P>0.05) ; CMH+ALA饲粮和CMH+LMA饲粮显著增加生长育肥猪眼肌面积 (P<0.05) ; CMH饲粮和CMH+ALA饲粮显著降低生长育肥猪背最长肌滴水损失和压榨损失 (P<0.05) ; CMH饲粮和CMH+Tau饲粮显著提高生长育肥猪背最长肌肉色亮度和黄度值以及蒸煮损失 (P<0.05) , 显著降低肉色红度值 (P<0.05) ; CM H饲粮、CM H+ALA饲粮和CM H+Tau饲粮显著提高生长育肥猪背最长肌琥珀酸脱氢酶和肌酸激酶活性、总抗氧化能力和肌酸储备量 (P<0.05) , 显著降低背最长肌乳酸含量 (P<0.05) , 并以CM H+ALA饲粮改变程度最大; CM H饲粮和CM H+ALA饲粮显著提高生长育肥猪背最长肌肌酸转运蛋白基因相对表达水平 (P<0.05) , 后者改变大于前者且显著提高背最长肌肌红蛋白和肌球蛋白重链Ⅱa基因相对表达水平 (P<0.05) .综合上述结果可知, 饲粮添加CMH、CM H+ALA或Tau或LM A均能够降低生长育肥猪背膘厚度, 其中CM H+ALA组合添加综合表现出更好的胴体和肉质改善作用, 比单独添加CMH进一步提高了肌酸转运储备、氧化代谢能力、肌红蛋白表达和氧化型肌纤维比例等.%To improve the application of creatine monohydrate (CMH) in nutritional regulation on meat quality, this paper investigated the effects of dietary CMH and its combination additives on carcass composition, meat quality traits and metabolic molecular indices of growing-finishing pigs.A total of 100 Duroc×Landrace×Yorekshire crossed barrows (about 60 to 70 kg) were divided into five groups with twenty replicates in each group and one pig in each replicate.Pigs in the control group were fed the basal diet, and the others in four experimental groups were fed CMH diet (supplemented with 0.5 g/kg CMH in the basal diet) , CMH+α-lipoic acid (ALA) diet (supplemented with 0.5 g/kg CMH and 0.1 g/kg ALA in the basal diet) , CMH+taurine (Tau) diet (supplemented with 0.5 g/kg CMH and 0.1 g/kg Tau in the basal diet) and CMH+L-malic acid (LMA) diet (supplemented with 0.5 g/kg CMH and 0.5 g/kg LMA in the basal diet) , respectively.These pigs were fed for 50 days, and then slaughtered uniformly and sampled for measuring indices.The results showed that, compared with the control group, dietary CMH and its combination additives significantly decreased the back fat thickness (P<0.05) , and tended to increase moisture content and decrease crude lipid content in longissimus dorsi (P>0.05) of growing-finishing pigs;CMH+ALA diet and CMH+LMA diet significantly increased loin eye area of growing-finishing pigs (P<0.05) ;CMH diet and CMH+ALA diet significantly decreased drip loss and mill loss in longissimus dorsi of growing-finishing pigs (P<0.05) ;CMH diet and CMH+Tau diet significantly increased cooking loss, meat color lightness and yellowness values (P< 0.05) , and significantly decreased meat color redness value (P<0.05) in longissimus dorsi of growing-finishing pigs;CMH diet, CMH+ALA diet and CMH+Tau diet all significantly decreased lactic acid content (P<0.05) , and significantly increased activities of succinodehydrogenase and creatine kinase, total antioxidant capacity and creatine reserve content (P<0.05) in longissimus dorsi of growing-finishing pigs, while CMH+ALA diet got more greatly changes on the above metabolism indices;moreover, CMH diet and CMH+ALA diet significantly increased creatine transporter gene relative expressive level (P< 0.05) , and CMH+ALA diet exhibited more markedly increased degree than CMH diet;CMH+ALA diet rather than CMH diet significantly increased the relative expressive levels of myoglobin and myosin heavy chain Ⅱa genes (P<0.05) in longissimus dorsi of growing-finishing pigs.These results indicate that the dietary CMH, CMH+ALA or Tau or LMA can reduce the back fat thickness of growing-finishing pigs, and the combination of CMH+ALA can get a better carcass and meat quality improvement.The underlying mechanism may be further enhanced than individual supplementation of CMH to increase creatine transport reserve, oxidative metabolism, myoglobin expression, and the proportion of oxidized muscle fiber type of growing-finishing pigs.
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