THE INFLUENCE OF DIETARY-FAT SOURCE (SUNFLOWER OIL OR OLIVE OIL) ON LDL COMPOSITION AND SERUM-LIPID LEVELS IN MINIATURE SWINE (SUS-SCROFA)

A total of 24 miniature swine (Sus scrofa) were fed with two diets of 9% fat content, differing only in the quality of the fat source (sunfl ower oil and olive oil). Two groups of animals were fed for a 12-week period, and the other two groups were fed for a 50-week period. After the two experimental periods, the influence of the dietary fat on seru m lipids and protein and fatty acid composition of isolated LDLs was s tudied. In the short term, the serum cholesterol level was slightly hi gher in the olive oil group but, with the time of adaptation to the di et, serum levels of TC, FC and PL increased significantly in the sunfl ower group. In the long term, LDL and HDL were also significantly high er in the sunflower group when compared to the monounsaturated diet. I n the sunflower group, PROT/TC and PROT/LIP ratios decreased significa ntly with the experimental period, while in the olive oil group they i ncreased, due to the decrease in EC and TG fractions. The LDL particle in the olive group contained fewer saturated fatty acids and more mon ounsaturated fatty acids, specially oleic acid, than the LDL in the su nflower group. The changes found in chemical and fatty acid compositio ns of LDL, according to the saturation degree of the predominant fat o f the diet, could alter its cellular metabolism.