不同剂量甘露寡聚糖对鸡细胞免疫和肠道微生态的影响

45只1日龄海兰褐壳蛋鸡雄性雏鸡随机分成3组（Ⅰ、Ⅱ组分别在千克基础日粮中含甘露寡聚糖2、4g，Ⅲ组为对照组），试验期42d．结果表明，Ⅱ组鸡的白细胞吞噬率和PHA淋巴细胞转化率（27．6％，47．8％）与Ⅲ组（23．6％，43．8％）相比差异极显著（P＜0．01）；Ⅱ组鸡的白细胞吞噬率与Ⅰ组（25．3％）比较差异显著（P＜0．05）．Ⅰ组鸡白细胞吞噬率（25．3％）显著高于Ⅲ组（23．6％）（P＜0．05），PHA淋巴细胞转化率（47．1％）极显著高于Ⅲ组（43．8％）（P＜0．01）．Ⅱ组鸡盲肠大肠杆菌数（9．001亿）、盲肠和回肠内容物pH值（6．137、5．097）都极显著低于Ⅲ组（9．412亿，6．66、6．08）（P＜0．01）；Ⅰ组鸡盲肠大肠杆菌数（9．164亿）显著低于Ⅲ组（9．412亿）（P＜0．05），盲肠和回肠内容物pH值（6．253、5．258）都极显著低于Ⅲ组（6．667、6．08）（P＜0．01）．测试的各项指标除白细胞吞噬率外，Ⅰ组和Ⅱ组之间均无显著差异．日粮中添加甘露寡聚糖能显著提高鸡的细胞免疫功能，能通过改善肠道内环境，显著降低大肠杆菌数，促进有益的乳酸菌生长，降低场内容物的pH值．添加高剂量甘露寡聚糖对鸡肠道微生态的调节作用没有明显的累加效应，说明了肠道微生态的平衡在正常情况下具有一定程度的?

Effects of different levels of mannan-oligosaccharide on cellular immuneresponse and gastrointestinal microecology in chickens

Forty five one-day old male chickens of Hy-line were divided randomly into 3 groups, group Ⅰ, Ⅱ(basic diet respectively containing 0.2%, 0.4% ) and control (basic diet). All chickens were slaughtered at the age of 42 days. The results were as follows: (1) macrophage activity and PHA lymphoblast transforming rate are significantly higher in group Ⅱ than that in control (27.6% compared to 23.6 %; 47.8% compared to 43.8%, respectively) (P<0.01); macrophage activity in group Ⅰis significantly higher than that in control (25.3% compared to 23.6%) (P<0.05); PHA lymphoblast transforming rate is significantly higher in group Ⅰ than in control (47.1% compared to 43.8%) (P<0.01); (2) E. coli in ceca is significantly lower in group Ⅱ than in control (9.001×10 compared to 9.412×10) (P<0.01); and is significantly lower in group Ⅰ than in control (9.164×10 compared to 9.412×10) (P<0.05). pH in ceca and ileum of group Ⅱ (6.138, 5.097,respectively) and group Ⅰ (6. 253, 5. 258, respectively) are significantly lower than those (6. 667, 6. 08,respectively) of control (P<0.01). It is concluded that cell-mediated immunity was stimulated or enhanced,and cecal E. coli count and pH of ceca and ileum were reduced at the same time, by the improvement of intestinal microflora of chickens wlth MOS treatment. Because of no siginificent difference of all items except macrophage activity between group Ⅰ and group Ⅱ, there is no better influence on intestinal microflora with the treatment of higher level of MOS, indicating that microflora self-regulation may exist in the intestine of healthy chickens.