Dumonceaux Tim J, Hill Janet E, Hemmingsen Sean M, Van Kessel Andrew G
Department of Animal and Poultry Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK S7N 5A8, Canada.
Appl Environ Microbiol. 2006 Apr;72(4):2815-23. doi: 10.1128/AEM.72.4.2815-2823.2006.
The inclusion of antibiotic growth promoters, such as virginiamycin, at subtherapeutic levels in poultry feeds has a positive effect on health and growth characteristics, possibly due to beneficial effects on the host gastrointestinal microbiota. To improve our understanding of the chicken gastrointestinal microbiota and the effect of virginiamycin on its composition, we characterized the bacteria found in five different gastrointestinal tract locations (duodenal loop, mid-jejunum, proximal ileum, ileocecal junction, and cecum) in 47-day-old chickens that were fed diets excluding or including virginiamycin throughout the production cycle. Ten libraries (five gastrointestinal tract locations from two groups of birds) of approximately 555-bp chaperonin 60 PCR products were prepared, and 10,932 cloned sequences were analyzed. A total of 370 distinct cpn60 sequences were identified, which ranged in frequency of recovery from 1 to 2,872. The small intestinal libraries were dominated by sequences from the Lactobacillales (90% of sequences), while the cecum libraries were more diverse and included members of the Clostridiales (68%), Lactobacillales (25%), and Bacteroidetes (6%). To assess the effects of virginiamycin on the gastrointestinal microbiota, 15 bacterial targets were enumerated using quantitative, real-time PCR. Virginiamycin was associated with increased abundance of many of the targets in the proximal gastrointestinal tract (duodenal loop to proximal ileum), with fewer targets affected in the distal regions (ileocecal junction and cecum). These findings provide improved profiling of the composition of the chicken intestinal microbiota and indicate that microbial responses to virginiamycin are most significant in the proximal small intestine.
在禽类饲料中添加亚治疗水平的抗生素生长促进剂（如维吉尼亚霉素），对健康和生长特性有积极影响，这可能归因于其对宿主胃肠道微生物群的有益作用。为了更好地了解鸡的胃肠道微生物群以及维吉尼亚霉素对其组成的影响，我们对47日龄鸡的五个不同胃肠道部位（十二指肠袢、空肠中段、回肠近端、回盲交界处和盲肠）中的细菌进行了特征分析，这些鸡在整个生产周期中分别喂食不含或含有维吉尼亚霉素的日粮。制备了10个文库（来自两组鸡的五个胃肠道部位），每个文库包含约555 bp的伴侣蛋白60 PCR产物，并对10932个克隆序列进行了分析。总共鉴定出370个不同的cpn60序列，其回收频率在1到2872之间。小肠文库中以乳杆菌目序列为主（占序列的90%），而盲肠文库的多样性更高，包括梭菌目（68%）、乳杆菌目（25%）和拟杆菌门（6%）的成员。为了评估维吉尼亚霉素对胃肠道微生物群的影响，使用定量实时PCR对15个细菌靶点进行了计数。维吉尼亚霉素与胃肠道近端（十二指肠袢至回肠近端）许多靶点的丰度增加有关，而在远端区域（回盲交界处和盲肠）受影响的靶点较少。这些发现改进了对鸡肠道微生物群组成的分析，并表明微生物对维吉尼亚霉素的反应在小肠近端最为显著。
