This project examines the effect of plant extracts in the treatment of water mould infections and the effect of red algae as a feed supplement on disease resistance in trout and European perch. The project is supported by Migros.
There are two parts to this project: Enhanced immunocompetence in European perch and trout, and the control of water mould infections with the aid of plant extracts.
The relevance of these two project components lies in the generally prevalent lack of suitable medication in the aquaculture sector which strongly hampers the treatment of a range of diseases. In contrast to humans and other mammals, fish lack a specific immune system at hatch, rendering them very susceptible to a range of illnesses especially at the early stages of their lives. The enhancement of their non-specific immune system with the aid of certain red algae used as a food supplement may improve disease resistance and thus stress resistance in juvenile fish.
In trout reproduction, unfertilized eggs are easily infected with water moulds such as Saprolegnia spp. which can result in very significant losses. The most effective antifungal, malachite green, has been banned worldwide since 2006. Plant extracts may be a suitable alternative as all currently used substances have specific drawbacks or more limited effectiveness.