纳豆菌、甘露寡糖对仔猪肠道pH、微生物区系及肠黏膜形态的影响

Effect of Natto and MOS on Intestinal pH,Colonic Microflora Population and Intestinal Membrane Shape of Early Weaning Piglet

选取144头18日龄断奶,体重5.6 kg的杜大长三元杂仔猪,按体重和性别分成6个处理,每组3个重复,每重复8头仔猪,研究纳豆菌(Natto)和甘露寡糖(MOS)对早期断奶仔猪肠道pH、微生物区系和小肠黏膜形态的影响。结果为:(1)Natto、MOS均有降低仔猪肠道pH的趋势(P>0.05),Natto与MOS联用时显著降低仔猪空肠、回肠、盲肠和结肠内容物的pH(P<0.05);(2)Natto提高了仔猪结肠内容物中乳酸杆菌和双歧杆菌数量(P<0.05),提高结肠黏膜中乳酸杆菌数量(P<0.05),MOS提高了仔猪结肠内容物和黏膜中乳酸杆菌数量(P<0.05),2 g/kg的MOS组使结肠内容物和黏膜中大肠杆菌数下降(P<0.05)。Natto与MOS联用时内容物中大肠杆菌数量下降(P<0.05),乳酸杆菌数量显著高于金霉素组(P<0.05),黏膜中乳酸杆菌数量上升,大肠杆菌数下降,与空白组、金霉素组有显著差异(P<0.05);(3)Natto及联用组都显著提高了小肠黏膜的绒毛高度(P<0.05),但处理组间隐窝深度没有显著差异(P>0.05),Natto组、1 g/kg的MOS组及联用组的绒毛高度/隐窝深度比值显著上升(P<0.05)。试验说明,纳豆菌和甘露寡糖通过调节肠道内容物及黏膜中微生物区系,降低肠道pH,以维持仔猪肠黏膜正常的形态结构。

144 Duroc×Large white×Landrace crossbred piglets weaned at 18 d, weighted 5.6 kg, sorted by weight and gender, were allotted to 6 treatments, with 3 replicates per treatment and 8 piglet per replicate. The basal diet was corn-soybean, without antibiotics or probitotics, which was fed to the 1st group as negative control（CTL）. The 2nd group was fed with basal diets adding chlortetracycline hydrochloride （CTC） in 150 mg/kg as the positive control. The 3rd-Sth group were fed with basal diets adding 1 000 mg/kg Bacillus Natto sawamura （Natto） and 1 000 mg/kg or 2 000 mg/kg mannan oligosaccharides （MOS） respectively, the 6th group was fed with basal diets adding 1 000 mg/kg MOS and 500 mg/kg Natto. Intestinal pH, colonic gut flora population were examined, and the intestinal morphology were detected. The results were as follows. Dietary Natto and MOS supplementation have a trend of reducing pH value of jejunum, ileum, caecum and colon cotent, the intestinal pH were reduced significantly when Natto used combining with MOS. Dietary Natto increased lactobacillus and bifidobacterium population in colonic content, and lactobacillus population in mucous membrane increased, dietary MOS increased population of lactobacillus both colonic content and mucous membrane, group of 2 g/kg MOS reduced population of E.coli both colonic content and mucous membrane. In colonic content, cooperation of Natto and MOS had a suppressoion to E.coli compared with CTL and an enrichment of lactobacillus compared with CTC group （P〈0.05）, while in colonic mucous membrane, population of lactobacillus increased and E.coli decreased, with a remarkable difference to CTL and CTC group（P〈0.05）. Natto increased villus height of mucous membrane, as same as group of cooperation of Natto and MOS , There is no difference between each group for crypt depth of mucous membrane（P〉0.05）, the ratio of villus height and crypt depth of group Natto, 1 g/kg MOS, and the group of cooperation of Natto and MOS increasing remarkable compared to CTL group.