PRELIMINARY FINDINGS OF OPHTHALMOLOGICAL ABNORMALITIES IN FARMED HALIBUT

Ocular abnormalities occurring in farmed halibut at the Sea Fish Indus try Authority Marine Farming Unit, Ardtoe, Argyll were investigated cl inically and post mortem, A significant number of fish were found to h ave posterior polar cystic changes either causing scleral ectasia or g ross degenerative posterior segment abnormalities with chorioretinal a trophy, Other ocular abnormalities included cataract formation and int raocular inflammation, In a small number of fish gas bubble formation in the anterior chamber was observed during capture and examination, I t is possible that the lesions seen in these fish are a form of gas bu bble disease although super-saturation, the cause of gas bubble diseas e previously reported in farmed fish, does not occur in the tanks in w hich these fish are housed, While this paper provides no answers with regard to the aetiopathogenesis of the lesions, it is hoped that it wi ll stimulate discussion, leading to resolution of these questions thro ugh a multidisciplinary approach to the problem.