ANALYSIS OF THE GROWTH AND PIGMENTATION OF L. guttatus CULTIVATED IN FLOATING CAGES

The spotted rose snapper; Lutjanus guttatus, is the second most important snappers from commercial in the Mexican Pacific Ocean. The pigmentation of the skin presents problems when it is cultivated, losing commercial value due to the low skin color. The bioassays were designed providing the following diets: 1. Commercial diet+shrimp head (triplicate), 2.- Commercial diet (triplicate) and 3.- Fishes fed with natural food. The temperature, salinity, pH, dissolved oxygen, nitrites, nitrates, ammonium and phosphate were monitored. Biometric analyzes were performed every 10 days to calculate the supply of food rations. In 86 days of culture the Daily growth (1.40 gr) and Survival (73%). The treatment of feed/head of shrimp was the one that presented a better performance in the culture as well as in the pigmentation of the skin with carotenoids, at the beginning of the culture (2.44±1.01) and, at the end culture (17.31±6.57) vs without shrimp head beginning the culture (3.60±1.53) and at the end the culture (7.49±3.26). The results indicate that adding by-products such as shrimp head to red-skinned fish such as snapper L. guttatus increases skin pigmentation.