Malaltia d'hivern en la daurada: Optimització de l'estat nutritiu i immunològic

The increase in the aquaculture activity of gilthead sea bream in the Mediterranean area has shown a new pathology associated with the thermal decrease produced during the most cold months of the year (water by under 14ºC of temperature) wich provoke the dead of animals. This pathology is known as winter disease or winter syndrome. Field and experimental data have shown that this disease appear in animals of 100 to 300 g of weigh, which present a good apparent state, but with lesions of the digestive tract and the exocrine glands, and muscular fibers degeneration. The present project approaches the problem according to the following hypothesis: -There is an inmunodepresion caused by the temperature decrease, a status characteristic of the polikilotherms. -This depression is made worse by a previous history of malnutrition. The planning proposed is. 1. Obtainment of field data about nutritional and inmunitary status of the fish in the fish farms. 2. Experimental phase so "in vitro" as "in vivo" in order to approach possible solutions: diet formulation and experimental checking of its usefulness in the laborratory. 3. The third phase will consist in the accomplishment of a new field study with the new diet in the facilities used in the first phase. This phase will allow to conclude the degree of success of the formulated diet and its transfer to the fish farmers.