α-GML和植物精油对仔猪生产性能、养分表观消化率、肠道形态结构和肠道内微生物菌群的影响

Effects of α-GML and plant essential oils on performance, nutrient apparent digestibility, intestinal morphology and intestinal microbiota of piglets

为了了解α-月桂酸单甘油酯(α-GML)和植物精油对断奶仔猪生产性能、养分表观消化率、肠道形态结构和肠道内微生物菌群的影响,按照随机区组设计将日龄、体重接近的120头断奶仔猪分为对照组(饲喂基础日粮)和金霉素组、牛至油组、α-GML组、牛至油+α-GML组、复合植物精油组(分别饲喂添加100 mg/kg金霉素、100 mg/kg牛至油、500 mg/kgα-GML、50 mg/kg牛至油+250 mg/kgα-GML、100 mg/kg复合植物精油的基础日粮),每组4个重复,每个重复5头,试验期28 d,测定各组生产性能指标(平均日增重、平均日采食量和料重比),养分表观消化率,小肠(十二指肠、空肠和回肠)的绒毛高度、隐窝深度及肠绒毛高度/隐窝深度,盲肠和结肠内大肠杆菌和乳酸菌数量。结果表明:α-GML组日增重最高,分别比对照组和金霉素组高6.5%和8.4%(P>0.05);料重比最低,分别比对照组和金霉素组低4.5%和10.2%(P>0.05)。与对照组比较,α-GML组粗蛋白、粗脂肪、钙和磷的表观消化率均显著提高(P<0.05);牛至油组和α-GML组十二指肠、空肠和回肠绒毛高度显著提高(P<0.05),α-GML组十二指肠和空肠绒毛高度/隐窝深度显著提高(P<0.05),α-GML组十二指肠隐窝深度显著降低(P<0.05);牛至油+α-GML组盲肠和结肠乳酸菌数量显著提高(P<0.05)。说明在断奶仔猪的基础日粮中添加500 mg/kgα-GML能显著改善小肠绒毛结构,改善肠道微生态环境,提高饲料养分表观消化率;添加50 mg/kg牛至油+250 mg/kgα-GML能显著提高仔猪盲肠、结肠内容物乳酸菌的数量。

This experiment was conducted to investigate the effects of α-glycerol monolaurate(α-GML) and plant essential oil on performance, nutrient apparent digestibility, intestinal morphology and intestinal microbiota of weaned piglets. A total of 120 weaned piglets with similar body weight and age were randomly divided into control group(fed a basal diet), aureomycin group, oregano oil group, α-GML group, oregano oil +α-GML group and complex plant essential oil group(fed basal diet with 100 mg/kg aureomycin, 100 mg/kg oregano oil, 500 mg/kg α-GML, 50 mg/kg oregano oil +250 mg/kg α-GML,and 100 mg/kg complex plant essential oil respectively), 4 replicates per group and 5 piglets per replicate. The experiment lasted for 28 days. The performance indexes(average daily gain, average daily feed intake and feed to gain ratio), the nutrient apparent digestibility, the villus height, crypt depth and villus height/crypt depth of small intestine(duodenum, jejunum and ileum), and the number of Escherichia coli and lactic acid bacteria in the cecum and the colon were determined. The results showed as follows: the average daily gain in the α-GML group was the highest among all groups, which increased by 6.5% and 8.4% compared with that in the control group and the aureomycin group(P>0.05);the ratio of feed to gain was the lowest, which decreased by 4.5% and 10.2% compared with that in the control group and the aureomycin group, respectively(P>0.05). Compared with control group, the apparent digestibility of crude protein, ether extract, calcium and phosphorus was significantly increased in the α-GML group(P<0.05), the villus height in the duodenum, jejunum and ileum in the oregano oil group and the α-GML group, the villus height/crypt depth in the duodenum and jejunum in the α-GML group, and the number of lactic acid bacteria in the cecum and colon in the oregano oil +α-GML group were significantly increased(P<0.05), but the crypt depth in the duodenum in the α-GML group was significantly decreased(P<0.05). The results indicated that 500 mg/kg α-GML in the basal diet could significantly improve the intestinal villus structure and microecological environment, and increase the nutrient apparent digestibility of weaned piglets. The combination of 50 mg/kg oregano oil and 250 mg/kg α-GML could significantly increase the number of lactic acid bacteria in the cecal and colon contents of piglets.