OBJECTIVES

The objective of this study was to evaluate the efficacy of an otic solution (Otoclean®, Lab. Dr. Esteve, S.A.), in the cleaning of the ear canal of dogs in terms of evaluate the irritation of the product, removal of cerumen, control of erythema, and control of yeast number

MATERIALS

A total of 20 Beagle dogs, otherwise healthy, were randomly included in the study from a population of animals in the kennels of the Faculty of Veterinary Medicine of the Universitat Autònoma de Barcelona (Spain). 2-3 ml of Otoclean® were applied to the right ear canal of each dog for a total period of 30 days (once a day for the first 15 days and once every two days for the following 15 days). The left canal was left untreated. Three clinical examinations were performed on each animal during the study: before the start of the study and at days 15 and 30. The following operations were carried on during each examination: i) superficial and otoscopic examination of the ear canal in both ears of each animal to evaluate levels of existing cerumen and erythema, and ii) collection of samples from both ducts and cover-glass smear for cytological study.

RESULTS

Baseline levels of cerumen and erythema were homogeneous in both treated and untreated groups of ear canals. After 15 days of treatment, percentage of treated ear canals with a moderate to high level of cerumen decreased from 30% (baseline level) to 10%, being this value significantly lower (p<0.001) than the observed in the group of untreated ear canals. On the other hand, baseline level of erythema in the group of treated ear canals had nearly disappeared which was not the case in untreated ear canals. Mean number of yeast, counted through the microscope in three fields of 400X, had decreased by half in the samples obtained from treated ear canals, concretely from 19.6 to 8.4, whilst this value remained similar in the untreated ear canal group.

During examination of day 30, the results were similar to those observed during the previous examination, although the level of both cerumen and erythema in treated ear canals continued to decrease, which was not the case in untreated ear canals remain similar. Differences between groups observed during this examination were statistically significant (p<0.001) for both parameters. Finally, mean number of yeast detected in treated group during this examination was markedly lower than in the previous examination and, furthermore, significantly lower (p<0.001) than in untreated group (9.2 vs. 26.9 respectively).

CONCLUSION

According to the results, Otoclean®: i) presents a cleaning effect, removing existing cerumen from the ear canal of dogs and, therefore, decreasing one of the factors of predisposition for the appearance of external otitis in these species, ii) does not cause irritation to the ear canal, even helping to remove pre-existing erythema, probably in an indirect way by reducing the cerumen in the ear canal, and iii) contributes to the decrease the number of yeast present in the ear canals of dogs.