Abstract:
Eighteen cattle from different parts of Kerala, affected with ethmoid carcinoma were subjected to detailed investigations of the ocular changes. The incidence of eye involvement in cases of ethmoid tumour in cattle was assessed on the basis of reports or informations received from field veterinarians and cattle owners from different dietricts of Kerala. Incidence, clinical manifestations, intraocular pressure, gross pathological cbanges and biometry of the eye were studied. The effect of the tumour mass on the eye and the possible causes for the different ocular changes has been discussed. The highest incidence was found in the age group of six to ten years. The earliest case was recorded in a heifer aged four years. The frequency of the incidence was high in females (88%). Crossbred animals were found to be more affected (83%). The tumour was also encounter~d in three purebred cattle. Ninetyfour percent of the tumour affected animals showed exophthalmos either unilateral (82%) or bilateral (18%). Tbe left eye was affected in 14 percent and the right eye in 86 percent cases. It is suggested that 37 exophthalmos can be considered as a pathognomonic clinical manifestation for ethmoid tumour affected cattle. Blindness was observed in 90 percent of the affected eyes, ectropion in 85 percent cases and corneal cbanges in the form of keratitis or opaCities in 90 percent cases. Episcleritis, anterior uveitis, euphora, purulent discharges were the other clinical manifestations. Glauc~a, was found to be a characteristic feature in ethmoid caroinoma. Involvement of the optic nerve, optic diso, retina, vitreous and other deep structures of the eyes were also notioed by gross examination of the whole eye at autopsy. The lens showed varying degrees of displacement or luxation.
