Efficacy of Leptin and Linoleic Acid on Nuclear Succession and Early Embryos of Sheep Oocytes


  • Hussam Aryan University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Department of Veterinary Obestetrics, Gynecology and Reproduction, Cluj County, Romania https://orcid.org/0000-0001-8779-6352
  • Omar Mardenli University of Aleppo, Faculty of Agriculture, Department of Animal Reproductio, Aleppo, Syria
  • Liviu Bogdan University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Department of Veterinary Obestetrics, Gynecology and Reproduction, Cluj County, Romania
  • Ioan Groza University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Department of Veterinary Obestetrics, Gynecology and Reproduction, Cluj County, Romania


embryos, leptin, linoleic acid, oocytes, sheep


Hormones and fatty acids play a crucial role in enhancing the yield and quality of in vitro produced embryos. The present study aimed to assess the effectiveness of leptin and linoleic acid in increasing the in vitro maturation rate of ovine oocytes and the resulting competence of embryos. Two experiments were conducted. The first experiment aimed to investigate the nuclear status of oocytes at three maturation intervals (9, 21, and 28 hours), while the second experiment aimed to examine the cleavage rates and quality of  the resulting embryos. In both experiments, the  oocytes were matured in six maturation treatments, primarily consisting of TCM-199 supplemented with varying concentrations of leptin and linoleic acid. The control group, without any addition, was designated as T0, while increasing concentrations of leptin and linoleic acid were added to four treatments: T1 (50 nM.ml-1 and 10 µM, respectively), T2 (75 nM.ml-1 and 100 µM, respectively), T3 (100 nM.ml-1 and 200 µM, respectively), and T4 (150 nM.ml-1 and 1,000 µM, respectively). In the last treatment (T5), only 15% fetal calf serum was added. In comparison with the control (T0) and T5 treatments, matured oocytes in the T3 treatment achieved the highest rates of M-II (88.46% at 28 hours; p <0.001), cleavage (81.27%; p = 0.001), 2–8 cells (22.55%; p = 0.001), morula (11.27%; p = 0.04), blastocyst (66.18%; p = 0.001), and Type I embryo (47.55%; p = 0.02). In conclusion, the maturation of sheep oocytes in a combination of leptin (100 nM.ml-1) and linoleic acid (200 µM) through TCM-199 resulted in the highest rates of maturation and embryonic cleavage of excellent quality.

Author Biography

  • Hussam Aryan, University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, Department of Veterinary Obestetrics, Gynecology and Reproduction, Cluj County, Romania

    University of Agricultural Sciences and Veterinary Medicine, Faculty of veterinary medicine, Department of Veterinary Obstetrics, Gynecology and Reproduction, Cluj county, Romania


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Animal Science