MVSc.

The study was carried out in twelve clinical cases of dogs of either sex with history of affection of ear canal of different breeds and age groups presented to the Veterinary Hospitals of College of Veterinary and Animal Sciences at Mannuthy and Kokkalai to evaluate the endoscopic changes of the ear canal associated with otitis and its management.

The animals were subjected to detailed clinical examination to study the type and extent of lesions present. Microbial culture and antibiotic sensitivity of the otic discharge was done in all cases and animals were subjected to endoscopic evaluation of the ear canal to assess the extent of affection after administering atropine sulphate and xylazine hydrochloride for premedication followed by ketamine hydrochloride to effect anaesthesia.

The study revealed a higher incidence of otitis in German Shepherd Dogs. The incidence was more in male dogs than females with a mean age of 4.56 years. The symptoms observed included discharge from the affected ears, pawing and rubbing of the affected ear, shaking of the head, painful responses evinced while palpating the base of the ear, tilting of the head to the side of affection and drooping of the affected ear.

Physiological parameters of all the animals were within the normal range on the day of otoscopic examination. There were statistically significant variation in the mean temperature recorded on the day of endoscopic examination and the fourteenth day. Heamatological parameters recorded were within the normal range and there was no statistical variation between these parameters recorded on the day of endoscopic examination and on the fourteenth day.

Gram negative coccobacilli, Gram positive cocci, Gram negative short rods, Pseudomonas sp., and mixed culture of Gram negative short rods, Gram negative coccobacilli and fungal spores were isolated from the otic discharge. Majority of the isolates were Gram negative coccobacilli sensitive to gentamicin.

Endoscopic evaluation revealed inflammation of the ear canal with ulceration, stenosis and erythema of the lining of the canal. A nodular growth in the ear canal was observed in one case and presence of ear mite Otodectus cynotis were identified in another dog. The status of the tympanic membrane was assessed in cases were the tympanic membrane was visible otoscopically.

Radiographic changes noted in plain radiographs in dorso- ventral, lateral- oblique and rostro-caudal open mouth view include ossification of the external ear canal and thickening or lysis of the tympanic bulla.

Medical management of otitis was carried out with topical otic preparation containing ofloxacin, beclomethasone dipropionate, clotrimazole and lignocaine and oral antibiotics (cephalexin in nine dogs and one dog each with enrofloxacin and ciprofloxacin) and the response to the treatment was assessed endoscopically after fourteen days of treatment.