Assessment of the effects of diet and physical rehabilitation on radiographic findings and markers of synovial inflammation in dogs following tibial plateau leveling osteotomy.

OBJECTIVE To determine the effects of an omega-3 fatty acid and protein-enriched diet, physical rehabilitation, or both on radiographic findings and markers of synovial inflammation in dogs following tibial plateau leveling osteotomy and arthroscopic surgery for treatment of cranial cruciate ligament disease. DESIGN Randomized, prospective clinical trial. ANIMALS 48 dogs with unilateral cranial cruciate ligament disease. PROCEDURES Dogs were randomly assigned to receive a dry omega-3 fatty acid and protein-enriched dog food formulated to support joint health (test food [TF]), a dry food formulated for adult canine maintenance (control food [CF]), TF plus rehabilitation, or CF plus rehabilitation after surgery. Synovial fluid prostaglandin (PG) E2 and interleukin-1ß concentrations, radiographic osteoarthritis scores, osteotomy site healing, and patellar ligament thickness were assessed at predetermined time points up to 6 months after surgery. RESULTS Dogs that received CF had significantly higher PGE2 concentrations over time following surgery than did dogs that received TF, regardless of rehabilitation status. Synovial fluid interleukin-1ß concentrations did not change over time in any groups. Diet and rehabilitation were both associated with osteoarthritis scores, with significantly lower scores over time for dogs that received TF versus CF and for dogs that underwent rehabilitation versus those that did not. Proportions of dogs with complete osteotomy healing 8 and 24 weeks after surgery were significantly lower for dogs that received TF than for dogs that received CF, regardless of rehabilitation status. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that feeding the TF can result in lower synovial fluid PGE2 concentrations and that both the TF and rehabilitation can reduce progression of osteoarthritis in the 6 months following tibial plateau leveling osteotomy; clinical relevance of slower osteotomy healing in dogs fed the TF was unclear.

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. ANIMALS: 14 dogs (similarly housed and fed identical diets). PROCEDURE: 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 AND CLINICAL RELEVANCE: 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.

Application of molecular fingerprinting for qualitative assessment of small-intestinal bacterial diversity in dogs.

The aims of this study were to evaluate the use of molecular fingerprinting for assessment of bacterial diversity in canine duodenal juice and to evaluate the variation in the small intestinal microflora at repeated sampling. Two groups of dogs were used. Duodenal juice was collected from eight dogs euthanized for an unrelated project (group 1). Duodenal juice was also collected endoscopically from six dogs at weekly intervals for a total of 3 weeks (group 2). The variable V6-V8 region of bacterial 16S ribosomal DNA was amplified, and PCR amplicons separated by denaturing gradient gel electrophoresis (DGGE). The reproducibility of DGGE profiles and variations in bacterial diversity between dogs were evaluated by comparing similarity indices (Dice's coefficient; 100% represents complete identity) of DGGE profiles from group 1 dogs. Weekly variations in the flora of the small intestine were evaluated by comparison of DGGE profiles from different time points within the same individuals in group 2. The mean (+/- standard deviation) similarity of DGGE profiles of duodenal juice between the dogs in group 1 was 38.3 +/- 15.7% (range, 12.5 to 76.65%). There was a significantly higher variation in DGGE profiles between different dogs than between duplicates obtained from the same dog (P < 0.0001). DGGE profiles from samples collected at different time points varied within individuals, possibly due to variation over time or slight variation in sampling location. DGGE profiles indicate that dogs have a highly diverse microflora of the small intestine, with marked differences between individual dogs.