Comparative Clinical Evaluation of Systemic Antibiotic Regimens Combined with Tris-EDTA Flushing in Canine Pseudomonas Otitis Externa

Aims: The present study was conducted to compare therapeutic efficacy of three different treatment regimens in otitis externa caused by Pseudomonas spp. in dogs. Study Design: Clinical study involving canine otitis externa patients caused by Pseudomonas spp. in dogs were randomly divided into 3 different groups (group I, II and III) having 06 animals in each group. Dogs in each group were subjected to three different treatment protocols along with daily flushing of ear canal with TRIS EDTA and chlorhexidine solution to compare therapeutic efficacy. Place and Duration of Study: Ear swab samples from otitis externa affected dogs were collected for a period of 09 months from January to September, 2022 from Teaching Veterinary Clinical Complex, College of Veterinary Science and Animal Husbandry, Anjora, Durg (C.G.) and various Government Veterinary Hospitals and Private Pet Clinics in and around Durg district of Chhattisgarh. Methodology: Sterile ear swabs from clinical cases of otitis externa were processed for microbiological isolation and identification of Pseudomonas spp. based on the cultural, morphological and biochemical characteristics. All isolates were also subjected to antibiotic sensitivity testing as per standard protocol. Results: Antibiogram analysis of all Pseudomonas isolates demonstrated the highest susceptibility to imipenem (100%), followed by piperacillin–tazobactam (84.2%). In contrast, the lowest susceptibility rates were observed for amikacin and ceftriaxone (5.2% each). Clinical recovery was adjudged on the basis of restoration of clinical signs after treatment in affected dogs which revealed that oral marbofloxacin combined with daily Tris-EDTA and chlorhexidine flushing for two weeks achieved complete (100%) recovery in dogs with Pseudomonas otitis externa while animals treated with amoxicillin-clavulanic acid therapy resulted in an 83.33% recovery. However, enrofloxacin administered with the same flushing protocol was effective in 66.66% of Pseudomonas otitis affected dogs Conclusion: Oral marbofloxacin in combination with daily Tris-EDTA and chlorhexidine ear flushing for two weeks was found to be the most effective therapeutic protocol. Amoxicillin–clavulanic acid demonstrated moderate efficacy, whereas enrofloxacin showed comparatively lower clinical success. Overall, marbofloxacin-based therapy appears to be the most reliable treatment option for the management of Pseudomonas otitis externa in dogs. The findings of our study reveal that Pseudomonas otits externa in dogs needs to be addressed with appropriate therapeutic regimen for early recovery and prevent recurrence. The limitations of small sample size in our study needs to validated with larger population size for much stronger recommendations towards therapeutic management of Pseudomonas otitis externa in dogs.