To evaluation of blood biochemical parameters during breeding season, twelve number of Mehraban ewes were synchronized using intravaginal insertion of progesterone controlled internal drug release (CIDR). Estrous was stimulated through intramuscular injection of pregnant mare's serum gonadotropin (PMSG). Blood samples were collected at three time-points of breeding season (day 0, day 14th and day estrus). Values of triacylglycerol (TAG) and very low density lipoprotein (VLDL) obtained at day estrus were significantly lower than day 0 and day 14th (P<0.05). In contrast, values of cholesterol (Chol) and low density lipoprotein (LDL) were significantly higher (P<0.05) at day estrus compared with day 14th. No significant differences were identified for protein (PRO) and albumin in all three time-points. High correlation (r≥0.99) was represented between Chol and LDL at three time-points. Negative, negative and positive correlations were calculated between Chol and albumin at day 0, day 14th and day of estrus, respectively. Perfect correlation was identified between TAG and VLDL at three time-points. Apart of Chol as estradiol precursor, including LDL and albumin may be biochemical markers that utilize in ewes breeding season, routinely.
