Twenty-four heifers were allotted in a randomized block design in a 2 × 3 factorial arrangement (with or without the injection of hCG, three isoproteic diets) to evaluate the effect of different dietary lipid sources associated or not to hCG on the progesterone and lipid metabolite levels, and the cyclic luteal function of heifers in six different treatments. The progesterone concentration from the sixth to the 12th day postestrus were higher in heifers fed on hyperlipidemic diets than those fed on control diet. The hyperlipidemic diets were important in the lipidic metabolism profile, mainly from sixth to the ninth day after the onset of estrus because the interaction between the hCG and hyperlipidemic diets. The best lipidic metabolites to detect the lipometabolic alterations were the total cholesterol and high density lipoprotein (HDL). There was a positive correlation between the total cholesterol, HDL and progesterone concentration in postestrus animals. Total cholesterol and HDL probably can modify the luteal cyclic function of heifers and be the precursors in the esteroidogenic sinthesis in the ovary.
Heifer; hiperlipidemic diets; reproduction; hCG; lipid metabolics
