Proposed Dietary Solutions

Proposed solutions took two main routes. First was to switch to a lower energy/lower oil content diet so that, to maintain existing energy expenditure, fish had to call on the oil reserves within their muscle tissue. An alternative was to continue with the same diet but to use a reduced ration, again to encourage use of in-built stores. In short, changes to feeding management were deemed to be the answer rather than wholesale changes to the type of diet.

Reduction of energy input aided the gaping problem. This was thought to be a consequence of too rapid growth in muscle tissue resulting in incorrect tissue formation and insertion of muscle myofibrils into the myosepta. Thus, on filleting the muscle tissue tore very easily. The colour problem was associated with the fact that pigments used in fish diets are fat-soluble and with excess around, some pigment was being re-absorbed. These changes to feed management resulted in a resolution to the problem in time - it took several months as opposed to being an overnight cure.

The range of diets now available to farmers mean that they have the capability to produce the quality of fish required by the various market outlets through diet manipulation.