A simplified method of scoring cataracts in fish

With the increased incidence of cataracts being reported in farmed fish it has been important to monitor the degree and progression of these cataracts. This paper describes the different methods that are used and discusses the relative merits of each. A method of scoring the cataracts is described, 0= No cataract, up to 4= total opacity of the lens. The scoring method does not give detailed morphological information of the type of cataract seen but can be a useful epidemiological tool in assessing the cataract status in a population of fish.