Otitis media can be a consequence of chronic otitis externa and could represent a perpetuating factor. While the microbiota of the EEC in healthy dogs and in the presence of otitis externa has been described, only sparse information is available concerning the normal microbiota of the middle ear. The objective was to compare the tympanic bulla (TB) with the external ear canal (EEC) microbiota in healthy dogs. Six healthy experimental Beagle dogs were selected based on the absence of otitis externa, negative cytology and bacterial culture from the TB. Samples from the EEC and TB were collected directly after death using a total ear canal ablation and lateral bulla osteotomy. The hypervariable segment V1–V3 of the 16S rDNA was amplified and sequenced with a MiSeq Illumina. The sequences were analyzed by the Mothur software using the SILVA database. No significant differences between the EEC and TB microbiota for the Chao1 richness index (p = 0.6544), the Simpson evenness index (p = 0.4328) and the reciprocal Simpson alpha diversity (p = 0.4313) were noted (Kruskal-Wallis test). A significant difference (p = 0.009) for the Chao1 richness index between the right and left EEC was observed. The microbiota profile was similar in the EEC and the TB of the Beagles.

To assess the rigidity of Robert-Jones Bandage (RJB) used to stabilize a standardized in vitro fracture model, under cyclic compression/bending. In vitro cyclic testing study. wooden rods divided into two segments of identical length by a Cardan Joint enclosed in a thick foam tube and supported by a RJB. Part 1: incremental loading applied to 6 specimens in successive stages of 50 N from 5 to 150 to 5-300 N with 3000 cycles per stage. Part 2: 9 specimens were loaded at 150 N (5-150 N) during 60,000 cycles. The Wilcoxon signed-rank test was used to compare data obtained at 10,000 and 60,000 cycles. In part 1, 6/6 specimens withstood 150 N for 3000 cycles. Three specimens endured an additional 3000 cycles at 200 N, 2 withstood 250 N for another 3000 cycles, and 1 tolerated 300 N. In part 2, 9/9 specimens withstood 150 N for 60,000 cycles, with displacements ranging from 0.102 mm to 0.309 mm (mean 0.179 ± 0.069 mm) and a median rigidity of 897 ± 375 N/mm. No specimen reached the fixed displacement limit of 2 mm after 60,000 cycles. No statistically significant difference was found between the results at 10,000 and 60,000 cycles (p = 0.129). The Robert-Jones Bandage showed consistent rigidity under prolonged cyclic loading in an in vitro fracture model. While this in-vitro model cannot replicate the influence of soft tissues, joint motion, or multidirectional physiological forces, the findings suggest that a properly applied Robert Jones bandage may provide short-term mechanical support to a long-bone fracture prior to definitive stabilization. However, clinical applicability should be interpreted with caution given the inherent limitations of the experimental setup.