Effect of Selenomethionine or Yeast Enriched with Selenium on Reproductive Performance, Progesterone and Estrogen Hormones in Iraqi Ewes

Abstract

This study was conducted at the animal farm affiliated with the college of agriculture, university of anbar, ramadi, iraq, to investigate the effects of selenomethionine or selenium-enriched yeast on the reproductive performance and hormone levels (progesterone and estrogen) in Iraqi ewes. the study was carried out from July 26, 2022, to january 27, 2023. eighteen ewes with an average age of 2-3 years and an average body weight of 43 ± 2.5 kg were used. the ewes were randomly divided into three equal groups, with six ewes in each group. all ewes were fed the same ration. group 1 served as the control group and received no treatment, while group 2 was treated with selenomethionine at a dose of 0.03 g/kg/bw. group 3 was treated with selenium-enriched yeast (saccharomyces cerevisiae-selenium) at the same dose, following the guidelines of the national research council (nrc, 1980). the treatments were administered orally for 45 days by dissolving the samples in 30 ml of distilled water. blood samples were collected from the jugular vein to assess changes in hormone concentrations. the results showed a significant increase in progesterone levels during the second period for groups 1 and 2 compared to group 3 (p ≤ 0.01). group 1 exhibited a significant increase in the time of the first appearance of estrus and the average time for estrus compared to group 2. group 2 showed a significant increase in estrus rate compared to group 1 and group 3. both group 2 and group 3 exhibited a significant increase in fertility rate, fertilization rate, pregnancy rate, and lambing rate. group 2 and group 3 also showed a significant increase in fecundity, twinning rate, and litter size compared to group 1. In conclusion, the supplementation of Selenomethionine and Selenium-enriched yeast positively affected reproductive performance in Iraqi ewes, as evidenced by improved hormone levels, estrus characteristics, fertility rates, and lambing outcomes.