An analysis of the ion-exchange characteristics of fish-egg chorions

The chorions of rainbow trout were investigated to measure their ion-exchange characteristics. These characteristics have been incorporated into a model, based on ion-exchange theory, which attempts to describe interactions between chorions and a range of water qualities, in terms of the distribution of K⁺. The model was tested by comparing predicted K⁺ accumulation by chorions with that actually measured in experimental conditions. The model successfully predicted the influence of combinations of K⁺ and Ca²⁺ on K⁺ accumulation, and was able to predict the direction of changes in K⁺ accumulation in the presence of aluminium and low pH.