The eye is an organ within which the immune reactions, because of a particular physiology, frequently develop. Recent studies have enabled these different diseases to be classified. Their identification, the aim of diagnosis, is often easy. It may call upon biological, serological examinations or more usually on biopsies. Cyto-patho-anatomical observation and direct immuno fluorescent are of particular interest. The treatment of A. I. O. D. has recourse to anti-inflammatories and to general immnosuppressants but also, when possible, to topical drugs, collyrium and ointment which are less toxic for the organism. Therapeutic evolution is directed towards less toxicity and greater efficacy.

The spontaneously epileptic rat (zi/zi, tm/tm: SER), a double mutant obtained by mating tremor rats (+/+, tm/tm) and zitter rats (zi/zi, +/+), exihibits characteristic absence-like seizures and tonic convulsions without external stimuli. These epileptic rats have extensive spongy changes in the brain including the brainstem. These findings stimulated us to perform further morphological and functional studies on the visual organ in these mutants.

Five males each of tremor rats, zitter rats, SER and Kyo: Wistar rats (control), 6 and 10 to 12 weeks of age, were subjected to eye examination.

No remarkable change was observed in SERs or tremor rats in ophthalmoscopic examination. Zitter rats showed mild tortuosity and narrowness of the retinal artery.

ERGs revealed prolongation of b-wave latency, increase of a- and b-waves amplitude, splitting and indistinctness of oscillatory potential were recorded in zitter rats and SERs. In biochemical examination, the dopamine content in the retina was significantly decreased in zitter rats compared with that in Kyo: Wistar rats. The dopamine content in the retina of SERs was lower, though not statistically significant, than that of Kyo: Wistar rats. Histopathological examination revealed abundunt vacuole-like gaps between the external plexiform and outer granular layers in the retina in zitter rats and similar gaps in the inner granular layer in SERs. In addition, hypomyelinization was observed in the optic nerve in SERs and zitter rats.

Tremor rats, however, showed no remarkable change in ERG findings, dopamine contents, and histopathological examinations.

Thus, we concluded that the retinal abnormality observed in SERs was ascribable to the zi/zi gene from the zitter rat; however, the changes in the retina were more marked in zitter rats than in SERs.

Diplomates of the American College of Veterinary Ophthalmologists provide a well-organized basic course of comparative ophthalmology for veterinary students and an advanced training program for residents. The course of comparative ophthalmology at the Ohio State University and the training program for residents are described. In addition, the fundamental approach to ophthalmic abnormalities as taught to veterinary students is discussed.

Most of the ophthalmological instruments used in animal experimentation were designed originally for use on human beings and therefore are often inconvenient in experiments using rabbits, which are frequently used for testing of this eye drops and so on. The objective of the present trial was to overcome the inconvenience and we succeeded in producing a stressless restraint apparatus and an easy-to-operate observation table for rabbits. The holding box was made of aluminum and designed so as to minimize stress on the rabbit by providing adequate space for the rabbit to stretch its front legs and to lower the position of its neck, and the weight of the device was reduced to make it portable. The observation table was made of metal, mainly aluminum, and was sustained by a coupled pair of pantagraphs for ease of height adjustments. A small roller bearing assisted pantagraph was used for angle adjustment. The weight of the table was kept to a minimum in order to lighten the burden on the apparatus.

The experimental use of these trial models revealed a significant reduction in injuries and less change in physical condition of the rabbits. Also, the observation table permitted the operator to work alone and perform examinations and recording within a shorter period of time.

Corneal opacity was found in a female Japanese white rabbit. On slit lamp biomicroscopic examination (KOWA SL-5), the opacity was present in both eyes where well demarcated rectangular opacity occupied most of the central part of the cornea with its long axis parallel to the palpebral fissure. The lesions appeared to be composed primarily of myriads of evenly dispersed coarse granules. A vertical linear dense band ran across the rectangles. There were no other notable changes in either of the eyes.

Histological examination of these corneas revealed disarrangement of the subepithelial lamella structure. The collagen fibers in the regions of the opacity were swollen, arranged haphazardly and formed a disoriented corneal stromal mass. Toward the periphery of the corneas, a few persistent capillaries were apparent. There also was cellular infiltration consisting primarily of plasma cells at each limbus. Special staining including PAS and Von Kossa was negative for the stromal lesions.

On the basis of these findings, the corneal opacity most likely represented a chronic stage of keratitis. The etiology is uncertain, but probably traumatic.

A survey of veterinary practitioners living in the western part of Japan was carried out in July, 1991. All of these veterinarians thought that ophthalmological aspects of their practice were very important, but the frequency of surgical operations was not high. They desire to receive information on new drugs, standard operating procedures for emergency ophthalmological treatment, details on the latest treatments and techniques, special lectures, etc. A majority of the respondents, particularly the younger ones, desire to visit overseas eye clinics and related facilities for research or training. The main candidate countries were those of North America and Europe. The respondents also wish to hear lectures by active veterinarians from these countries.