1INRA, UR1213 Herbivores, Site de Theix, F-63122 Saint-Genès-Champanelle, France.
Animal. 2007 Aug;1(7):939-44. doi: 10.1017/S1751731107000304.
Bacteria attached to the rumen epithelium (or epimural community) are not well characterised and their role in rumen functioning is not totally understood. There is just one published report of a clone library from one cow that suggests that this epimural community differs from the bacteria associated with the rumen digestive contents. However, this time-consuming approach is not adapted for examining microbial population changes in groups of animals. In in vivo studies, when samples from several animals have to be analysed simultaneously, a simpler technique has to be used. In this study, a genetic fingerprinting technique, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), was used to characterise the structure of the bacterial population attached to the rumen epithelium. This community was compared with that present in the solid and liquid phases of rumen content under two contrasting diets. Rumen samples were obtained from four forage-fed and four high-concentrate-fed (80 : 20, wheat grain : hay) 5-month-old lambs. After slaughter, samples from five epithelial sites and the solid and liquid digesta phases were taken for DNA extraction and analysis. Bacterial communities were profiled by PCR-DGGE using bacterial-specific 16S rDNA primers. Analysis of the fingerprint revealed that the epithelial community differed from those of rumen content in both diets. As expected, the nature of the feed influenced the bacterial communities from the solid and liquid rumen phases but no diet effect was observed in the rumen epithelial profiles suggesting a strong host effect on this bacterial population. Additionally, no differences were observed among the five epithelial sampling sites taken from each animal. The profile of the bacterial population attached to the rumen epithelium presented a high inter-animal variation, whether this difference has an influence in the function of this community remains to be determined.
附着于瘤胃上皮（或附壁生物群落）的细菌尚未得到很好的描述，其在瘤胃功能中的作用也不完全清楚。仅有一篇从一头奶牛获得的关于附壁生物群落的克隆文库的报道表明，该附壁生物群落与与瘤胃消化内容物相关的细菌不同。然而，这种耗时的方法并不适用于检查动物群体中微生物种群的变化。在体内研究中，当需要同时分析多个动物的样本时，必须使用更简单的技术。在这项研究中，使用聚合酶链反应-变性梯度凝胶电泳（PCR-DGGE）这一遗传指纹图谱技术来描述附着于瘤胃上皮的细菌种群的结构。将该群落与在两种截然不同的日粮下存在于瘤胃内容物的固体和液体相中的群落进行了比较。从 4 头采食粗饲料和 4 头高浓度精料（80:20，小麦粒：干草）的 5 月龄羔羊中获得瘤胃液样本。屠宰后，从五个上皮部位以及固体和液体消化物中取样进行 DNA 提取和分析。使用细菌特异性 16S rDNA 引物通过 PCR-DGGE 对细菌群落进行分析。指纹图谱分析表明，上皮群落与两种日粮下的瘤胃液群落不同。正如预期的那样，饲料的性质影响了来自固体和液体瘤胃相的细菌群落，但在瘤胃上皮图谱中没有观察到日粮的影响，这表明该细菌种群受到强烈的宿主影响。此外，从每个动物的五个上皮采样部位获得的细菌种群的图谱没有差异。附着于瘤胃上皮的细菌种群的图谱呈现出高度的个体间变异性，这种差异是否会对该群落的功能产生影响还有待确定。
