Epidemiological Analysis of Ear Diseases in 221 Dogs in Northwest of China

Ear disease is a relatively common disease in veterinary, and it will great effect on the pets’ life. This study mainly collected and collated the cases of Xi’an Teaching Hospital of Northwest A&F University from 2012 to 2016, and conducted an epidemiological analysis of the incidence of ear disease in dogs. In this study, the common ear diseases in dogs were divided into otitis externa, otitis media, otitis interna, and ear hematoma. The results showed that the total number of dog ear disease cases was 221, the highest incidence was otitis externa (84.62%), and the main cause of otitis externa was the bacterial infection (44.10%), which followed by fungal infection (32.31%). The ratio of male to female is 1:1.5. In terms of the dog species, the highest incidence was Teddy (18.55%), followed by the Golden Retriever (10.41%). The most common ear diseases in puppies was otitis externa, ear canal hyperplasia and ear canal tumors occur mainly in older dogs. Through the analysis of the 221 cases of ear diseases, we could better understand the development and epidemiology of dog ear diseases, and provide some reference for clinical diagnosis, treatment and prevention of dog ear diseases. In recent years, with the continuous improvement of people’s quality of life, more and more people choose to keep pets to accompany themselves, and the number of pets in Xi’an has also increased sharply. However, ear disease is one of common diseases in dogs, their characteristics include pruritus, long treatment period and easy to relapse. If the treatment is not timely, there may be secondary otitis media and otitis interna, which may affect the hearing of dogs. In severe cases, neurological symptoms may occur, which may have a bad impact on the life and health of dogs. Now, we have collected and sorted out a total of 221 cases of ear diseases in dogs from Xi’an Teaching Hospital of Northwest A&F University from 2012 to 2016, and classified them into four directions: otitis externa, otitis media, otitis interna and ear hematoma for epidemiological analysis, so as to provide references for the clinical diagnosis and treatment of ear diseases in dogs in the future.

months was shown in Figure 4.

Investigation results of dog ear diseases in different breeds
107 The results of this study had showed that the top three breeds of ear diseases in Xi'an were 108 Teddy, Cocker Spaniel and Golden Retriever, accounting for 18.55%, 10.41%, and 9.50% of 109 the total cases respectively. The incidence of different breeds was shown in Table 4. The number of ear diseases showed a tendency to increase with time gradually in Table 1. and the average annual number of dog ear diseases was 44. According to this data, the incidence 122 of ear diseases was still relatively high in the small animal clinic, accounting for more than 10%

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As can be seen from figure 2, the highest incidence of otitis externa is bacterial infection, 152 and the common bacteria in the ear canal mainly are Staphylococcus, Pseudomonas and Proteus.

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In the experiment, the microorganisms in the ear canal of healthy dogs and affected dogs were

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The third is external parasites, and the main causes of this disease is Otodectes cynotis. Its

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The fourth is allergic diseases. The auricle is an extension of the skin on the surface of the 183 body. In the statistical cases, the cause of allergy were mainly foreign body or IgE. When 184 animals are exposed to allergens many times, which stimulates B cells to produce IgE, and of organ is not yet fully mature, the barrier function and the immunity of skin is relatively weak.

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Secondly, young dogs enjoy outdoor activities and they may be exposed to many allergens, 201 such as ear mites, which increases the risk of allergies. For elderly dogs, the secretion of sebum

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Among the collected cases, there were 133 male cases, accounting for 60.18% of the total 225 cases, which was more than 39.82% of females (Fig.3)

The relationship between the incidence of canine ear disease and the season 239
As can be seen from Figure 4, the high incidence of ear diseases in Xi'an is from June to

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First, Xi'an has a large rainfall in the summer and autumn, with a long rainy period and a 250 high air humidity. However, the structure of the ear canal is relatively closed, and the moist 251 environment is beneficial to the growth of microorganisms, which increases the incidence of

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Third, we generally think that the degree of hair growth in the external auditory canal may 264 have an effect on the temperature of the ear canal, which will increase the temperature of the ear canal, and the higher temperature is conducive to the reproduction of microorganisms. Beijing. In recent years, the number of Teddy, Pomeranian, and Golden Retriever in Xi'an has 305 increased, so the incidence has also increased greatly. Secondly, some hairy breeds, such as 306 schnauzer and teddy, which get regular haircut. When plucking hair of ear canal, the external 307 force will destroy the stratum corneum of the ear canal skin, and the defense of skin is weakened,

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it is prone to cause ear diseases.

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We are grateful to all of those who helped with this study, especially to hospital staff of