BACKGROUND: Studies indicate elements and vitamins play an important role in reproductive function activities.
OBJECTIVES: The present study was concluded to investigate the effect of organic and inorganic selenium supplements along with vitamin E to improve the properties of estrus in Ghezel ewes using CIDR.
METHODS: Forty-four Ghezel ewes (Age: 2-3 years old, weight: 55±2 kg, body condition score 3) were used. Animals allocated in four groups including eleven ewes in each group. Treatments were divided into four groups: first group: As a control group (basal diet), the second group (basal diet + Barley grain), the third group (basal diet + Barley grain + vitamin E + selenium organic), and the forth group (basal diet + Barley grain+ vitamin E + inorganic selenium). Ewes received the experimental diets 2 weeks before mating and continued 3 weeks later. Oestrus was synchronized using CIDR.
RESULTS: The highest and the lowest rate of return to estrus were observed in control group (45.5%) and in the fourth group (18.2%) respectively (P<0.01). Moreover, the first observed estrus after CIDR removal was belonged to third group which was significantly different compared to other groups (P<0.01). The estrogen levels of third and fourth groups during proestrus and estrus and progesterone concentration of third and fourth groups in 21 days after mating were significantly different from groups control and second group (P<0.01).
CONCLUSIONS: It seems that the use of flushing diets containing organic and inorganic selenium along with vitamin E increased the estrus, the probability of fertilization and decreased the non-pregnant ewes.