日粮添加蛋氨酸对宫内发育迟缓生长猪肠道发育和抗氧化功能的影响

目的:研究蛋氨酸对宫内发育迟缓(intrauterine growth retardation,IUGR)生长猪肠道发育和抗氧化功能的调节作用。方法:30头正常初生体质量(normal birth weight,NBW)和60头IUGR仔猪于21日龄断奶,分别随机分成3个处理组,即NBW-CON组(NBW仔猪饲喂基础(control,CON)日粮),IUGR-CON组(IUGR仔猪饲喂基础日粮),IUGR-MET组(IUGR仔猪饲喂蛋氨酸(methionine,Met)日粮),每个处理组6个重复,每个重复5头猪,实验期为84 d。结果:IUGR-CON组猪空肠和回肠绒毛高度(villus height,VH)、空肠绒毛表面积、回肠蔗糖酶和麦芽糖酶活力、空肠OCLN m RNA相对表达量较NBW-CON组猪显著降低(P0.05)。与NBW-CON组猪相比,IUGR-CON组猪空肠丙二醛(malondialdehyde,MDA)含量显著升高(P0.05),空肠还原型谷胱甘肽(reduced glutathione,GSH)含量和GSH/氧化型谷胱甘肽值显著降低(P0.05),回肠超氧化物歧化酶活力显著降低(P0.05)。日粮添加蛋氨酸可显著增加IUGR猪空肠VH,升高回肠麦芽糖酶活力,上调空肠OCLN m RNA相对表达量(P0.05)。同时,蛋氨酸可显著缓解IUGR介导生长猪空肠MDA含量升高与GSH含量降低(P0.05)。结论:蛋氨酸可降低IUGR猪肠道脂质过氧化程度,改善肠道抗氧化能力,一定程度上缓解了IUGR对生长猪肠道发育的不良影响。

Effect of Dietary Methionine Supplementation on Intestinal Development and Antioxidant Function in Growing Pigs with Intrauterine Growth Retardation

Objective: In order to investigate the effect of dietary methionine supplementation on intestinal development and antioxidant function in growing pigs with intrauterine growth retardation (IUGR). Methods: At postnatal day 21, thirty normal birth weight (NBW) female piglets and sixty same-sex IUGR piglets were weaned. The NBW piglets were allocated to the NBW control (NBW-CON) group, and the IUGR piglets were randomly assigned to the IUGR control (IUGR-CON) and methionine supplementation (IUGR-MET) groups. The piglets were thus distributed across three groups for a 84 d of feeding trial, and each group consisted of six replicates with five piglets per replicate. Results: IUGR-CON pigs exhibited a reduction in villus height (VH) in both the jejunum and ileum, villus surface area in the jejunum, the activities of sucrase and maltase in the ileum, and OCLN mRNA expression in the jejunum when compared with NBW-CON pigs (P < 0.05). Compared with NBW-CON pigs, IUGR-CON pigs had increased malondialdehyde (MDA) content in the jejunum, decreased reduced glutathione (GSH) content and GSH/oxidized glutathione ratio in the jejunum, and superoxide dismutase activity in the ileum (P < 0.05). Dietary methionine supplementation significantly increased VH in the jejunum, maltase activity in the ileum, and OCLN mRNA expression in the jejunum of IUGR pigs (P < 0.05). A higher methionine inclusion alleviated the increased MDA content and the decreased GSH content in the jejunum of IUGR pigs (P < 0.05). Conclusion: Dietary methionine supplementation attenuates lipid peroxidation and improves antioxidant capacity in the intestine, which may be associated with the partially improved intestinal development in IUGR pigs.