饲粮短期高剂量添加天冬氨酸镁对猪肉品质的影响

本试验研究了在基础日粮中短期添加不同水平的天冬氨酸镁对猪肉品质的影响。试验共分4个处理,每个处理6头猪。处理组镁(天冬氨酸镁)的添加水平分别为0、1 500、2 500和3 500 mg/kg。结果表明:屠宰前7 d饲粮添加天冬氨酸镁提高了猪肉品质,背最长肌肉中镁的含量分别比对照组提高了10.35%(P<0.05)、16.83%和18.61%(P<0.01),血清中镁的浓度分别比对照组增加了14.29%、27.14%和34.29%(P<0.01);显著提高了猪肉的初始pH(6.16~6.50)和最终pH(5.61~5.75)(P<0.05);对肉色评分改善显著(P<0.05);显著降低了滴水损失(P<0.05);但对猪的屠宰率、瘦肉率、背膘厚、眼肌厚度和肌肉中胶原蛋白含量等无显著影响(P>0.05)。回归分析结果表明:当镁的添加量在2 500~3 200 mg/kg时,对pH、滴水损失和肉色的改善作用达到最大,此时血清和肌肉中镁的含量约为0.90 mmol/L和241 mg/kg。

Effects of High Level Magnesium Aspartate on Meat Quality of Pigs for Short Time

To explore the effects of magnesium aspatate supplementation in the basal diet for 7 day prior to slaughter on meat quality of pigs,twenty-four pigs were randomly divided into four treatments of 6 pigs each.The levels of magnesium aspatate supplementation were 0,1 500,2 500 and 3 500 mg/kg of Mg contents.The results showed that dietary MgAsp supplementation improved the meat quality.Longissimus thoracis(LT) and serum magnesium levels were significantly increased by 10.35%(P<0.05),16.83%,18.61%(P<0.01) and 14.29%,27.14%,34.29%(P<0.01) respectively after feeding the MgAsp diet.The pH values of LT muscle at 45 min and 24 h after slaughter were significantly raised(P<0.05).Pigs fed the MgAsp had lower percentage of drip loss amd higher color score than those of the control(P<0.05).There were no significant differences in dressing rate,lean percentage,backfat thickness,eye muscle thickness and collagen content regardless of MgAsp supplementation or not(P>0.05).The result of regression analysis indicated that supplementation of Mg at doses of 2 500 to 3 200 mg/kg could result in the optimal meat pH value,meat color and drip loss.The corresponding Mg contents in serum and LT muscle were about 0.9 mmol/L and 241 mg/kg respectively.