胍基乙酸对育肥猪肉品质和抗氧化能力的影响

本试验旨在研究日粮添加不同浓度胍基乙酸（GAA）对育肥猪生长性能、肉品质和抗氧化能力的影响。140头健康的体重相近的育肥猪，随机分为4个处理，分别饲喂在基础日粮中添加0（对照组）、300、500和700 mg/kg的GAA，饲养期为35天。饲养过程中记录体重和采食量，屠宰时采集背最长肌和血浆样品用于肉品质和抗氧化指标分析。日粮添加GAA对育肥猪日采食量、日增重均有提高的趋势，对料重比也有降低的趋势（P>0.05），显著降低平均背膘厚（P<0.05）；添加GAA可以显著提高育肥猪背最长肌宰后45 min的pH值，降低滴水损失、蒸煮损失和剪切力值（P<0.05），对肉色影响不显著（P>0.05）；添加GAA显著提高血浆中谷胱甘肽过氧化物酶活性和总抗氧化能力，降低丙二醛含量（P<0.05）；添加GAA显著提高背最长肌中超氧化物歧化酶活性和总抗氧化能力，降低丙二醛和羰基含量（P<0.05）。育肥猪日粮中添加GAA可以改善背最长肌肉品质，增强机体的抗氧化能力。

Effect of Guanidinoacetic Acid Supplementation on the Meat Quality and Antioxidant Capacity of Finishing Pigs

The aim of this study was to investigate the effect of guanidinoacetic acid (GAA) supplementation on the growth performance, meat quality and antioxidant capacity of finishing pigs. A total of 140 healthy finishing pigs with roughly equal weight were randomly assigned to 4 groups, and were fed a basal diet supplemented with 0 (control), 300, 500 or 700 mg/kg GAA for 35 days, respectively. During the feed period, the body weight and consumption of feed were recorded for the calculation of growth performance, and the samples of the longissimus dorsi muscle and plasma were collected to measure the meat quality and the antioxidant index after slaughter. Compared with the control group, GAA supplementation tended to increase the average daily feed intake and average daily gain, and decrease the feed/gain ratio (P>0.05), and decrease the back fat depth significantly (P<0.05). In addition, GAA treatments showed significant increase in the pH value at 45 min postmortem, and decrease in the drip loss, cooking loss and shear force value (P<0.05). However, there was no difference in the meat color among these groups (P>0.05). Moreover, dietary GAA increased the activity of glutathione peroxidase and total antioxidant capacity, and decreased the concentrations of malondialdehyde in the plasma (P<0.05). Meanwhile, the pigs subjected to GAA treatments had higher activity of superoxide dismutase and total antioxidant capacity, and lower concentrations of malondialdehyde and carbonyl in the longissimus dorsi muscle (P<0.05). Dietary GAA supplementation could improve the meat quality and enhance the antioxidant capacity of finishing pigs.