复合维生素B对山羊生长性能及肠道微生物区系的影响

Effects of dietary supplementation with different doses of vitamin B-complex on the growth performance and microflora composition in goats

本研究旨在探索日粮中添加不同剂量复合维生素B对山羊生长性能和肠道菌群组成的影响。试验选取20只3-4月龄,体重为(16.78±1.52)kg的波杂山羊,在基础日粮中分别添加0 mg/kg复合维生素B(对照组,C),低剂量复合维生素B组(含1.2 mg/kg维生素B1、2.4 mg/kg维生素B2、2.4 mg/kg维生素B3、2.4 mg/kg维生素B5、1.2 mg/kg维生素B6、8μg/kg维生素B12)(低剂量组,L);中剂量复合维生素B组含维生素B添加剂量为低剂量组的5倍(中剂量组,M);高剂量复合维生素B组含维生素B添加剂量为低剂量组的10倍(高剂量组,H)。每组5只山羊,试验期为56 d。试验期间自由采食和饮水,记录山羊的体重及采食量,试验结束时采集血液和新鲜粪便并采用生化分析法和454高通量测序法检测相关生理指标和粪便中微生物组成。结果显示,复合维生素B处理56 d后,与C组相比H组山羊的增重升高的同时料重比显著下降(P<0.05),H组血液生化指标中总蛋白(TP)和球蛋白(GLOB)含量显著降低(P<0.05),但L和M组无显著变化(P>0.05)。高通量测序的结果表明,厚壁菌门和拟杆菌门在山羊粪便中为优势菌门,H组α-多样性物种相对丰度和ACE指数均显著低于C组(P<0.05),但C和M组的α多样性分析无显著差异(P>0.05)。普雷沃氏菌等有益菌在H组显著高于C组(P<0.05),M组相比C组则无显著变化(P>0.05)。结果提示,日粮补充复合维生素B可提高波杂山羊的生长性能,高剂量组复合维生素B效果较好,且维生素B促进山羊生长可能与肠道中普雷沃氏菌等有益菌的丰度增加有关。

The aim of this study was to explore the effects of vitamin B-complex on the growth performance and intestinal microflora composition in goats. Twenty 3-4 months old crossbred boer goats with body weight of 16.78±1.52 kg were fed with basal diet supplemented with 0 mg/kg vitamin B-complex(the control group, C), low doses of vitamin B complex(1.2 mg vitamin B1, 2.4 mg vitamin B2, 2.4 mg vitamin B3, 2.4 mg vitamin B5, 1.2 mg vitamin B6, 8 ug vitamin B12) per kg diet(the low-dose group, L), moderate doses of vitamin B with 5 times those in the L group(the moderate-dose group, M), and the high-dose vitamin group with 10 times those in the L group(the high dose group, H). There were 5 goats in each group. All the animals enjoyed free access to water and food during the experimental period for 56 d, when their body weight and feed intake were recorded. Their blood and fresh feces samples were collected at the end of the experiment. Then, biochemical methods and 454 high-throughput sequencing were performed to measure the blood parameters and fecal microflora composition in feces. The results showed that, compared with the control, the H group showed significant increase in their weight gain,but decrease in their feed weight ratio(P<0.05), and significant decrease in their blood total protein(TP) and globulin(GLOB) levels(P<0.05). However, there were no significant changes among the C, L and M groups(P> 0.05). The results of high throughput sequencing showed that Firmicutes and Bacteroidetes were the dominant bacteria in the feces of the goats. Alpha diversity analysis showed that the relative abundance and ACE index of the species in the H group were significantly lower than those in the C group(P<0.05).Beneficial bacteria such as Prevotella copri was significantly higher in the H group than in the control group(P<0.05),but no significant changes were observed in the M group(P>0.05).These results indicated that dietary vitamin B-complex supplementation improved the growth performance of goats,which might be related to the changes in intestinal microflora and the abundance of beneficial bacteria such as Prevotella copri.