Assessment of the qualitative variation in bacterial microflora among compartments of the intestinal tract of dogs by use of a molecular fingerprinting technique.
OBJECTIVE
To evaluate the qualitative variation in bacterial microflora among compartments of the intestinal tract of dogs by use of a molecular fingerprinting technique.


METHODS
14 dogs (similarly housed and fed identical diets).


METHODS
Samples of intestinal contents were collected from the duodenum, jejunum, ileum, colon, and rectum of each dog. Bacterial DNA was extracted from the samples, and the variable V6 to V8 region of 16S ribosomal DNA (gene coding for 16S ribosomal RNA) was amplified by use of universal bacterial primers; polymerase chain reaction amplicons were separated via denaturing gradient gel electrophoresis (DGGE). Similarity indices of DGGE banding patterns were used to assess variation in the bacterial microflora among different compartments of the intestine within and among dogs. Bacterial diversity was assessed by calculating the Simpson diversity index, the Shannon-Weaver diversity index, and evenness.


RESULTS
DGGE profiles indicated marked differences in bacterial composition of intestinal compartments among dogs (range of similarity, 25.6% to 36.6%) and considerable variation among compartments within individual dogs (range of similarity, 36.7% to 579%). Similarities between neighboring intestinal compartments were significantly greater than those between non-neighboring compartments. Diversity indices for the colon and rectum were significantly higher than those of the duodenum, jejunum, and ileum.


CONCLUSIONS
Results indicated that the different intestinal compartments of individual dogs appear to host different bacterial populations, and these compartmental populations vary among dogs. In dogs, fecal sample analysis may not yield accurate information regarding the composition of bacterial populations in compartments of the gastrointestinal tract.
Suchodolski
Jan S
JS
Gastrointestinal Laboratory, Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843-4474, USA.
Ruaux
Craig G
CG
Steiner
Jörg M
JM
Fetz
Kathrin
K
Williams
David A
DA
D000818:Animals; D001419:Bacteria / Q000235:genetics*; D044822:Biodiversity; D016000:Cluster Analysis; D016172:DNA Fingerprinting / Q000379:methods / Q000662:veterinary*; D004285:Dogs / Q000382:microbiology*; D004586:Electrophoresis / Q000662:veterinary; D007422:Intestines / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012336:RNA, Ribosomal, 16S / Q000235:genetics
D012336:RNA, Ribosomal, 16S