本试验旨在研究乳铁蛋白( lactoferrin,LF)对滇撒配套系断奶仔猪生产性能、血清抗氧化指标及组织抗氧化基因表达量的影响. 选用(28±2)日龄滇撒配套系断奶仔猪192头,随机分为4个处理,每个处理6个重复,每个重复8头,对照组饲喂基础饲粮,LF1、LF2和LF3 3个试验组在基础饲粮基础上分别添加125、250 和500 mg/kg的 LF. 饲喂42 d 后,测定平均日增重( ADG)、平均日采食量( ADFI)、料重比( F/G)和腹泻率. 采用试剂盒检测血清总抗氧化能力( T-AOC)、总超氧化物歧化酶( T-SOD)活力、丙二醛( MDA)含量和谷胱甘肽过氧化物酶( GSH-Px)活力,采用实时荧光定量PCR(RT-qPCR)法测定心脏和肝脏谷氧还蛋白1(GRX1)、硫氧还蛋白1(TRX1)、超氧化物歧化酶(SOD)及GSH-Px基因表达量. 结果表明:1)与对照组相比, LF2和LF3组显著提高了ADG、ADFI(P<0.05),LF1 和LF2 组显著降低了料重比(P<0.05), LF2和LF3组显著降低了仔猪的腹泻率( P<0.05). 2)血清中,与对照组相比,LF1( P<0.05)、LF2(P<0.01)和 LF3 组(P<0.05)T-SOD 活力均显著或极显著提高;LF2 组 GSH-Px 活力及T-AOC均显著提高(P<0.05);LF2和LF3组的MDA含量均显著降低(P<0.05). 3)与对照组相比,LF1和LF2组GRX1、SOD和GSH-Px基因在心脏和肝脏中的表达量均增加,其中LF1组肝脏GSH-Px差异显著(P<0.05),LF2 组肝脏 GRX1、SOD 和 GSH-Px 差异极显著(P<0.01);LF1组TRX1基因在肝脏中的表达量极显著提高( P<0.01);LF3组GRX1、TRX1基因在肝脏和心脏中及SOD、GSH-Px基因在心脏中的表达量均降低,其中心脏GRX1、TRX1和SOD差异极显著( P<0.01). 结果提示:在断奶仔猪饲粮中添加一定量的LF(本试验添加250 mg/kg最佳)可提高断奶仔猪的生长性能,提高血清抗氧化指标及心脏和肝脏中抗氧化基因GRX1、TRX1、SOD和GSH-Px的表达量.
This experiment was conducted to investigate the effects of lactofferin ( LF ) on growth perform-ance, serum antioxidant indices and tissue antioxidant gene expressions in Diansa weaned piglets. A total of 192 Diansa weaned piglets at the age of (28±2) days were randomly divided into 4 groups with 6 replicates in every group and with 8 piglets in every replicate. The control group was fed a basal diet, and LF1, LF2 and LF3 groups were respectively supplemented with 125, 250 and 500 mg/kg LF in the basal diet. Average daily weight ( ADG) , average daily feed intake ( ADFI) , feed to gain ratio ( F/G) and diarrhea rate were deter-mined after feeding 42 days. Kits were used for detecting serum antioxidant indices: total antioxidant capacity ( T-AOC) , total superoxide dismutase ( T-SOD) activity, malondialdehyde ( MDA) content and glutathione peroxidase ( GSH-Px) activity. The expression levels of glutraredoxin 1 ( GRX1) , thioredoxin 1 ( TRX1) , su-peroxide dismutase ( SOD) and GSH-Px genes in heart and liver were detected by real-time quantitative PCR ( RT-qPCR) . The results showed as follows: 1) compared with control group, LF2 and LF3 groups signifi-cantly improved ADG and ADFI ( P<0.05) , LF1 and LF2 groups significantly ( P<0.05) reduced F/G, and LF2 and LF3 groups significantly reduced dairrhea rate ( P<0. 05 ) . 2 ) In serum, compared with control group, T-SOD activity were significantly increased in LF1 (P<0.05), LF2 (P<0.01) and LF3 (P<0.05) groups, GSH-Px activity and T-AOC in LF2 group were significantly increased ( P<0.05) , and the contents of MDA in LF2 and LF3 groups were significantly decreased (P<0.05). 3) Compared with control group, the expression levels of GRX1, SOD and GSH-Px genes in heart and liver were increased in LF1 and LF2 groups. In liver, the difference of GSH-Px gene in LF1 group was significant (P<0.05), and those of GRX1, SOD and GSH-Px genes in LF2 group were extremely significant (P<0.01). TRX1 gene expression level in LF1 group was extremely significantly increased ( P<0.01) . The expression levels of GRX1 and TRX1 genes in both tissues, SOD and GSH-Px genes in heart in LF3 group were decreased. and the differences of GRX1, TRX1 and SOD genes in heart was extremely significant ( P<0. 01 ) . The results suggest that the additon of LF (250 mg/kg was the best in this study) with a certain amount in diets can improve growth performance of weaned piglets, and enhance antioxidant capacity of piglets by improving the serum antioxidant indices and up-regulating antioxidant gene expressions.