低蛋白饲粮对杜长大猪生长性能、肉品质和抗氧化的影响

Effects of low protein diets on growth performance,meat quality and antioxidant capacity of pigs

【目的】研究低蛋白饲粮下添加氨基酸对生长育肥猪生产性能、肉品质和抗氧化活性的影响。【方法】选取平均体质量(24.6±0.95)kg/头杜洛克×长白×大白杂交猪(杜长大杂交猪)63头,随机分3组,即对照组(基础饲粮)、低蛋白Ⅰ组(粗蛋白水平较对照低1%)和低蛋白Ⅱ组(粗蛋白水平较对照低2%),每组3个重复,每个重复7头猪,试验期105 d,分为3个饲养阶段,第1阶段猪体质量为25~50 kg/头,第2阶段为50~75 kg/头,第3阶段为75~110 kg/头,研究低蛋白饲粮对保育-生长-育肥全期杜长大猪生长性能、肉品质、抗氧化能力和血液生化指标的影响。【结果】与对照组相比,2个低蛋白处理组的平均日采食量、平均日增质量、料重比均无显著差异(P>0.05)。各组间的肉质红度a^(*)、黄度b^(*)、亮度L和蒸煮损失无显著差异(P>0.05);而低蛋白Ⅱ组滴水损失较对照组显著增加(P<0.05)。与对照组相比,低蛋白处理组超氧化物歧化酶(SOD)活性显著提高(P<0.05)。低蛋白Ⅱ组总抗氧化能力(T-AOC)较对照组显著提高,总胆固醇含量与低蛋白Ⅰ组相比显著升高(P<0.05),其他血液生化指标总蛋白、白蛋白、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和尿素氮含量与对照组和低蛋白Ⅰ组间均差异不显著(P>0.05)。【结论】在补充氨基酸的基础下饲喂低蛋白饲粮,对生长育肥猪的生长性能、肉品质、血液生化指标无显著负面影响,且可在一定程度上提高肌肉抗氧化能力。

【Objective】This study investigated the effects of low protein diet supplemented with amino acids on growth performance,meat quality and antioxidant capacity of pigs.【Method】A total of 63 Duroc×Landrace×Large White hybrid pigs with an average body weight of(24.6±0.95)kg were randomly divided into three groups of control(basic diet),low-protein groupⅠ(crude protein level 1%lower than the control)and low-protein groupⅡ(crude protein level 2%lower than the control).There were three replicates in each group,with 7 pigs in each replicate.The experimental period of 105 days were divided into three stages according to weight.The first stage was 25-50 kg/head,the second stage was 50-75 kg/head,and the third stage was 75-110 kg/head.The effects of low-protein diet on growth performance,meat quality,antioxidant capacity and blood biochemical indexes in hybrid pigs in the conservation-growth-fattening period was then investigated.【Result】There were no significant differences in average daily gain,average daily feed intake and F/G among the three groups(P>0.05).No significant differences in minolta color a^(*),color b^(*),color L^(*)and cooking loss were observed among the three diets(P>0.05),while the drip loss was markedly increased in low protein-dietⅡcompared with control group(P<0.05).The superoxide dismutase(SOD)activity in muscle of low proteinⅠandⅡgroups was significantly increased(P<0.05).Compared with control group,low-protein dietⅡincreased the total antioxidant capacity(T-AOC).Total cholesterol content in low-protein groupⅡwas significantly higher than that in low proteinⅠgroup(P<0.05),while there were no significant differences in other blood indexes TP,ALB,TG,HDL-C,LDL-C,BUN between three groups(P>0.05).【Conclusion】Low protein diets enhanced antioxidant capacity of pork without having negative effects on growth performance,meat quality and blood biochemical indexes in growing-finishing pigs.