Comparison between Cultured Small-Intestinal and Fecal Microbiotas in Beagle Dogs

Abstract

The microbiota of the small intestine is poorly known because of difficulties in sampling. In this study, we examined whether the organisms cultured from the jejunum and feces resemble each other. Small-intestinal fluid samples were collected from 22 beagle dogs with a permanent jejunal fistula in parallel with fecal samples. In addition, corresponding samples from seven of the dogs were collected during a 4-week period (days 4, 10, 14, and 28) to examine the stability of the microbiota. In the jejunal samples, aerobic/facultative and anaerobic bacteria were equally represented, whereas anaerobes dominated in the fecal samples. Despite lower numbers of bacteria in the jejunum (range, 10 2 to 10 6 CFU/g) than in feces (range, 10 8 to 10 11 CFU/g), some microbial groups were more prevalent in the small intestine: staphylococci, 64% versus 36%; nonfermentative gramnegative rods, 27% versus 9%; and yeasts, 27% versus 5%, respectively. In contrast, part of the fecal dominant microbiota (bile-resistant Bacteroides spp., Clostridium hiranonis-like organisms, and lactobacilli) was practically absent in the jejunum. Many species were seldom isolated simultaneously from both sample types, regardless of their overall prevalence. In conclusion, the small intestine contains a few bacterial species at a time with vastly fluctuating counts, opposite to the results obtained for the colon, where the major bacterial groups remain relatively constant over time. Qualitative and quantitative differences between the corresponding jejunal and fecal samples indicate the inability of fecal samples to represent the microbiotas present in the upper gut.

Cecal drop reflects the chickens' cecal microbiome, fecal drop does not

“…Three different kinds of studies can be distinguished: the first group of studies consider fecal samples to be a reliable sample in quantifying and identifying the bacteria in the gut (Claesson et al, 2011), the second group limits the use of fecal samples to monitoring shifts in the microbiota of the gut (Mai et al, 2004;Lubbs et al, 2009) and the last group considers fecal samples to be of limited use as a reference for the gut microbiota (Eckburg et al, 2005;Mentula et al, 2005). In our study, fecal drop showed a bacterial diversity, richness and community composition that is low compared to cecal content.…”

Dominance of Lactobacillus acidophilus in the Facultative Jejunal Lactobacillus Microbiota of Fistulated Beagles

“…However, it is argued that fecal samples cannot represent the microbiota present in the upper gut since they are different niches and provide specific habitats for different microbiota (17). Therefore, studies based on GI samples are needed to reflect the actual community in GI tract.…”

P1A Recombinant β-Lactamase Prevents Emergence of Antimicrobial Resistance in Gut Microflora of Healthy Subjects during Intravenous Administration of Ampicillin

“…Counting of anaerobic and aerobic microbial groups and species in fecal samples was performed by standard culture techniques (15,26). The total counts of Bacteroides fragilis group, Bifidobacterium spp., Lactobacillus spp., Clostridium spp., coliforms, Streptococcus spp., and yeasts were enumerated (detection limit, 10 2 CFU/g), and isolates were identified by established methods (24,26). The presence of Clostridium difficile toxins A and B in diarrheal samples was determined with a commercial kit (Premier Toxins A&B; Meridian Diagnostics).…”

“…Additionally, 10 colonies of coliforms (or as near to 10 as possible) at each time point, including all visibly different morphotypes, were isolated at random from blood and cysteine lactose electrolyte-deficient agar plates. The isolated coliformic colonies were identified to the species level by established methods (24,26).…”

“…In dogs, orally administered P1A recombinant ␤-lactamase was shown to effectively degrade the GI residue of intravenously administered ampicillin, ampicillin-sulbactam, amoxicillin-clavulanate, and piperacillin-tazobactam (10,11,24,33). Studies using mouse models demonstrated that oral administration of P1A recombinant ␤-lactamase given in conjunction with ampicillin or piperacillin preserved colonization resistance, reduced antibiotic-associated alteration in the indigenous microflora, and prevented overgrowth of vancomycinresistant enterococci and Clostridium difficile (35,36,37).…”