Epidemiological Investigation of Bacterial, Fungal and Parasitic Factors Causing Otitis externa in Dogs and Cats in Northern Iran from 2019 to 2021

Abstract

Otitis externa is a multifactorial disease that has 5 to 20 percent prevalence in small animal medicine which can be diagnosed according to the history and general dermatological and otoscopic examinations. This study aimed to compare the agents that cause Otitis externa in dogs and cats, taking into account the breeds, gender, and age differences of these animals. The samples were taken from 63 dogs and cats that were suspected of having external ear infections and referred to veterinary clinics from north of Iran, including Mazandaran, Guilan, and Golestan provinces, within 24 months (from April 2019 to April 2021). After obtaining the consent, sampling was performed from the pinna and the end of the vertical ear canal. The prevalence of infection observed in dogs was: 28.57% for Malassezia, 28.57% for gram-positive bacteria, 11.91% gram-negative bacteria, 16.67% and 14.28% for Otobius megnini and Sarcoptes scabiei respectively, while in cats, the prevalence of Malassezia infections was 9.52%, 23.80% gram-positive bacteria, 19.04% gram-negative bacteria, 19.04% Otobius megnini, and 33.34% Notoedres cati. There was no statistically significant difference between the studied dogs and cats with the variables of age, gender, and breed. Identifying the agents causing external ear infections and paying attention to factors such as etiologies, geographical effects, region climate, disease-causing agents, breed differences, gender, and age in Iran is crucial and can improve the rate of success in management and treatment of external ear infections. Therefore, it seems that due to the limited number of these studies in Iran, additional studies in this field are necessary. Among dogs and cats in the north of Iran, this study represents the first assessment of external otitis.