本试验以松辽黑猪为试验对象，研究宰前短期高钙日粮对猪肌钙含量和μ-calpain活性及其mRNA表达量的影响。选取健康、初重为(90.2±2.8) kg的松辽黑猪48头，随机分成8组，每组6个重复，每个重复1头猪。试验期为7 d。对照组饲喂基础日粮，试验组日粮分别在基础日粮中添加Ca2+浓度为0、0.5%、1.0%和1.5%的CaCl2或甲酸钙。结果表明：与对照组相比，CaCl2和甲酸钙均可显著(P<0.05)或极显著(P<0.01)提高肌钙含量和μ-calpain活性，其中以1.0%甲酸钙组效果最明显；甲酸钙可以提高μ-calpain的mRNA相对表达量，1.0%甲酸钙组与其他各组差异显著(P<0.05)；甲酸钙处理下，肌钙与μ-calpain在宰后熟化第3天和第9天存在着显著的正相关(P<0.05)。由结果可知，CaCl2和甲酸钙做为宰前肥育猪日粮中短期超量添加的钙源，均可达到提高肌钙含量和μ-calpain活性的目的，在本试验条件下以1.0%的甲酸钙(以Ca2+浓度计)效果最好。

This trial was conducted to study the effects of high dietary calcium within short term feeding on muscular calcium content, activity and mRNA expression of μ-calpain of Songliao black swines. Forty-two Songliao black swines with an initial weight of (90.2±2.8) kg were randomly allotted to 8 groups with 6 replicates each and 1 swine in each replicate. The trial lasted for 7 days. The control group was fed basal diets (contained Ca2+ of 0.5%, without CaCl2 and calcium formate), the experimental groups were fed basal diets with 0, 0.5%, 1.0% and 1.5% CaCl2 and calcium formate, respectively. The results showed as follows: compared with control group, CaCl2 and calcium formate increased the content of muscular calcium and activity of μ-calpain (P<0.05), and 1.0% calcium formate group had the best effect; calcium formate could increase the relative expression of μ-calpain mRNA, and the relative expression of μ-calpain mRNA of 1.0% calcium formate group was significantly higher than those of other groups (P<0.05). There was a significant positive relation between muscular calcium and activity of μ-calpain under the treatment of calcium formate after 3 d and 9 d of slaughtering (P<0.05). In conclusion, calcium chloride and calcium formate as the source of calcium in short term feeding of finishing pigs before slaughter could increase the content of muscular calcium and activity of μ-calpain, and the 1.0% calcium formate group had the best effect in this research. ［Chinese Journal of Animal Nutrition, 2009，21(6):960-966］