NUTRITIONAL PROPERTIES OF 4 MARINE MICROALGAE FOR ALBINO-RATS

The nutritive value of the marine microalgae Tetraselmis suecica, Isoc hrysis galbana, Dunaliella tertiolecta and Chlorella stigmatophora was studied in diets given to rats. Biological assays were carried out in order to determine the Protein Efficiency Ratio (PER) and the Food Co nversion Efficiency (FCE). Each dried microalga was fed to weaning Wis tar albino rats as the sole protein source at a protein level of 12%. Control rats were given diets containing 12% casein. Food consumption was similar in all groups. PER values obtained were 1.14 with T. sueci ca diet, 1.13 with I. galbana diet, 2.07 with D. tertiolecta diet and 1.13 with C. stigmatophora diet (casein, 2.50). FCE values followed a similar pattern. The data showed that the marine microalga D. tertiole cta is a source of protein of good quality. Its PER is quite high, com pared to vegetable and cereal proteins, and compares favourably with o ther microbial protein sources, such as yeasts or different freshwater microalgae. Haematological tests showed no significant differences am ong the groups in haemoglobin levels, red and white blood cell counts, differential count and mean corpuscular volume. Different blood param eters were also determined and a significant decrease in triglycerides levels appeared with all the microalgal diets, whereas a significant decrease in cholesterol appeared in D. tertiolecta and C. stigmatophor a diets.