谷氨酰胺对脂多糖应激仔猪生长性能及血清生化指标的影响

本试验旨在研究饲粮中添加谷氨酰胺(Gln)对断奶仔猪不同阶段生长性能的影响,以及其对脂多糖(LPS)诱导肠道损伤后断奶仔猪血清生化指标和生长性能的影响。选用24头28日龄健康的"杜×长×大"三元杂交断奶仔猪,随机分为3组,每组8个重复,每个重复1头猪。对照组和LPS组饲喂基础饲粮,Gln+LPS组饲喂添加了1%的外源性Gln的基础饲粮;在试验第22、25、28、30天,LPS组和Gln+LPS组腹腔注射100μg/kg BW LPS,对照组则注射相同剂量的生理盐水。试验期30 d。结果表明:1)LPS处理前(试验第1~21天),与对照组相比,Gln+LPS组显著提高了试验第1~7天断奶仔猪的平均日采食量(ADFI)和平均日增重(ADG)(P0.05),显著提高了试验第8~14天和第1~21天断奶仔猪的ADFI(P0.05)。2)LPS处理后(试验第22~30天),对照组断奶仔猪的ADFI、ADG、第30天体重均显著高于LPS组和Gln+LPS组(P0.05),Gln+LPS组断奶仔猪的ADFI、ADG、第30天体重均高于LPS组(P0.05)。3)LPS组断奶仔猪的小肠长度显著低于对照组和Gln+LPS组(P0.05),而对照组和Gln+LPS组之间无显著差异(P0.05)。4)与对照组相比,Gln+LPS组断奶仔猪的血清高密度脂蛋白胆固醇(HDLC)含量和碱性磷酸酶(ALP)活性显著降低(P0.05),而Gln+LPS组与LPS组之间无显著差异(P0.05);Gln+LPS组和LPS组断奶仔猪的血清免疫球蛋白M(Ig M)含量显著提高(P0.05)。由此可见,饲粮中添加1%的Gln能够显著提高仔猪断奶后第1~7天的生长性能,之后效果不明显。饲粮中添加1%的Gln能够调节应激仔猪的血清生化指标,改善其生长性能和小肠长度,从而缓解仔猪断奶应激。

Effects of Glutamine on Growth Performance and Serum Biochemical Parameters of Lipopolysaccharide Challenged Piglets

The objective of the study was to evaluate the effects of dietary glutamine ( Gln) supplementation on growth performance in the different stages, and the effects of Gln on growth performance and serum biochemi?cal parameters of weaned piglets after intestinal injury induced by lipopolysaccharide ( LPS ) . Twenty?four cross?bred (Duroc×Landrace×Yorkshire) piglets weaned at 28 days of age were randomly assigned into 3 groups with 8 replicates per group and 1 pig per replicate. Pigs in the control group and LPS group were fed the basal diet, and the others in the Gln+LPS group were fed the basal diet supplemented with 1% exogenous Gln. On day 22, 25, 28 and 30 of the trial, piglets in the LPS and Gln+LPS groups were administered intraperito?neally with 100 μg/kg BW LPS, whereas pigs in the control group were injected intraperitoneally with the same volume of sterile saline. The experiment lasted for 30 days. The results showed as follows: 1 ) before LPS challenge ( day 1 to 21 of the trial) , compared with the control group, the average daily feed intake ( AD?FI) and average daily gain ( ADG) of weaned piglets in Gln+LPS group were significantly increased on day 1 to 7 of the trial ( P<0.05) , the ADFI of weaned piglets in Gln+LPS group was significantly increased on day 8 to 14 and 1 to 21 of the trial (P<0.05). 2) After LPS challenge (day 22 to 30 of the trial), the ADFI, ADG and body weight on day 30 of weaned piglets in control group were significantly higher than those in LPS and Gln+LPS groups ( P<0.05) , the ADFI, ADG and body weight on day 30 of weaned piglets in Gln+LPS group were higher than those in LPS group ( P>0.05) . 3) The small intestine length of weaned piglets in LPS group was significantly lower than that in control and Gln+LPS groups ( P<0.05) , but there was no difference between the control group and Gln+LPS group ( P>0.05) . 4) Compared with the control group, the high den?sity lipoprotein cholesterol content and alkaline phosphatase activity in serum of weaned piglets in Gln+LPS group were significantly decreased (P<0.05), but there was no difference between the Gln+LPS group and LPS group ( P>0.05); the serum immunoglobulin M content of weaned piglets in Gln+LPS and LPS groups was significantly increased ( P<0.05) . The results indicate that dietary supplemented with 1% Gln can improve the growth performance of piglets after weaning 1 to 7 day, and then it is not obvious. Dietary supplemented with 1% Gln can regulate the serum biochemical parameters, improve the growth performance and small intes?tine length of piglets, thereby alleviate weaning stress.