Published February 12, 2026 | Version v1
Journal article Open

HORMONAL INFLUENCE ON OOCYTE DEVELOPMENT: AN EVALUATION OF LH AND FSH EFFECTS IN AWASSI AND HAMDANI SHEEP BREEDS

Authors/Creators

  • 1. Department of Pathological Analysis, College of Applied Medical Sciences, Al-Muthanna University,Al-rumaytha 66002, Iraq.

Description

This investigation aimed to assess the effects of circulating follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels on oocyte maturity in sheep of the indigenous Awassi and Hamdani breeds. Oocytes were obtained from 48 mature females and evenly distributed between the two breeds for experimental use. The same reproductive synchronization protocol was used for both breeds which included the insertion of a P4 (progesterone)-loaded intravaginal device followed by injecting pregnant mare serum gonadotropin (PMSG) after removal of the device. Blood samples for analysis of circulating gonadotropin levels (measured by ELISA) were collected from the jugular vein 48 hours after removal of the P4. Oocyte maturity was assessed morphologically using conventional light microscopic techniques. Statistical analysis of the data demonstrated significant differences between breeds in regard to oocyte maturity. The Awassi breed exhibited significantly higher levels of LH (0.41 ± 0.36) as well as a greater number of developmentally competent oocytes (76.48 ± 1.33) and fewer degenerative oocytes (10.29 ± 1.41) and immature gametes (13.38 ± 0.38) than the Hamdani breed. Additionally, the FSH (0.53 ± 0.19) levels of the Awassi were significantly higher than the Hamdani. Therefore, it can be concluded that gonadotropic hormones are important markers of oocyte developmental potential and that the Awassi breed has greater hormonal regulation and reproductive potential than the Hamdani breed. This data supports the concept that specific_ breed hormonal protocols stimulation could greatly enhance the success rate of assisted reproductive technologies and genetically selective breeding programs utilizing indigenous ovine genetic resources.

Files

401-Soft Copy.pdf

Files (1.1 MB)

Name Size Download all
md5:794d8665f69207f6a3e6670247dc108c
1.1 MB Preview Download

Additional details

Software

References

  • 1. Fortune, J. E. (2016). Ovarian follicular growth and development in mammals. Biology of Reproduction, 94(4), 86. https://doi.org/10.1095/biolreprod.115.134817 2. Ginther, O. J., Bashir, S. T., Hoffman, M. M., & Beg, M. A. (2018). Hormonal and follicular dynamics during the estrous cycle in sheep. Theriogenology, 112, 1–10. https://doi.org/10.1016/j.theriogenology.20 18.01.034 3. Webb, R., & Campbell, B. K. (2007). Development of the dominant follicle: mechanisms of selection and maintenance of oocyte quality. Theriogenology, 68(S1), S9–S15. https://doi.org/10.1016/j.theriogenology. 2007.04.036 4. Scaramuzzi, R. J., et al. (2011). A review of the effects of supplementary nutrition in the ewe on the concentrations of reproductive hormones. Reproduction Nutrition Development, 46(4), 339–354. https://doi.org/10.1051/rnd:2006021 5. Monniaux, D., Clément, F., Dalbiès-Tran, R., Estienne, A., Fabre, S., Mansanet, C., & Rico, C. (2014). The ovarian reserve of primordial follicles and the dynamic reserve of antral growing follicles: what is the link? Biology of Reproduction, 90(4), 85. https://doi.org/10.1095/biolreprod.113.117770 6. Baird, D. T. (2018). Endocrinology of follicular development and ovulation. Animal Reproduction, 15(3), 278–291. 7. Mossa, F., Duffy, P., Walsh, S. W., Butler, S. T., Berry, D. P., Carter, F., & Evans, A. C. O. (2012). Differences in follicular dynamics, gonadotropin and steroid concentrations, and progesterone receptor expression in high vs. low fertility cows. Reproduction, 143(5), 625–633. https://doi.org/10.1530/REP-11-0415 8. Al-Fatlawi, A. A., Al-Fatlawi, K. M., & Al-Husseiny, M. I. (2020). A comparative study on the reproductive performance of Awassi and Arabi ewes. Iraqi Journal of Veterinary Sciences, 34(2), 265–270. 9. Al-Khuzai, A. L., Al-Jobory, H. T., & Abbas, S. A. (2021). Reproductive performance of Awassi and Arabi ewes under Iraqi environmental conditions. Iraqi Journal of Veterinary Sciences, 35(2), 263–270. 10. Abecia, J. A., Forcada, F., & González-Bulnes, A. (2012). Hormonal control of reproduction in small ruminants. Animal Reproduction Science, 130(3–4), 173–179. https://doi.org/10.1016/j.anireprosci.2012.0 1.010 11. Bartlewski, P. M., Beard, A. P., & Rawlings, N. C. (2011). Ovarian function in sheep. Animal Reproduction Science, 126(1-2), 1–14. https://doi.org/10.1016/j.anireprosci.2011.04.006 12. Lonergan, P., & Fair, T. (2014). The ART of studying early embryo development: progress and challenges in ruminant embryo culture. Theriogenology, 81(1), 49–55. https://doi.org/10.1016/j.theriogenology.2013.09. 022 13. Paramio, M. T. (2010). In vitro maturation of oocytes in domestic ruminants. Animal Reproduction, 7(3), 162–169. 14. National Research Council. 2007. Nutrient Requirements of Small Ruminants: Sheep, Goats, Cervids, and New World Camelids. Washington, DC: The National Academies Press. 384 p. ISBN: 978-0-309-47324-8. DOI: 10.17226/11654 15. Ginther, O. J., Bashir, S. T., Hoffman, M. M., & Beg, M. A. (2018). Hormonal and follicular dynamics during the estrous cycle in sheep. Theriogenology, 112, 1–10. https://doi.org/10.1016/j.theriogenology.2018 .01.034 16. Souza, C. J. H., Campbell, B. K., & Baird, D. T. (2002). Follicular dynamics and ovarian steroid secretion in sheep. Reproduction, 123(6), 917–925. 17. Titi, H. H., Alnimer, M. A., & Obeidat, B. S. (2020). Reproductive responses of ewes to synchronization protocols. Animal Reproduction Science, 216, 106357. https://doi.org/10.1016/j.anireprosci.2020.106357 18. Nogueira, D., Vanhoutte, L., Dumortier, F., & De Sutter, P. (2009). Assessment of a new in vitro maturation system for mouse and human cumulus-enclosed oocytes: Three-dimensional prematuration culture in the presence of a phosphodiesterase 3-inhibitor. Human Reproduction, 24(8), 1946–1959. https://doi.org/ 10.1093/ humrep/dep104 19. Carvalho, A. A., Faustino, L. R., Castro, S. V., et al. (2013). Tissue thickness may influence the outcome of vitrification of goat ovarian cortex. Acta Scientiae Veterinariae, 41, 1150. 20. Lucci, C. M., et al. (2007). Osmotic tolerance and freezability of isolated caprine early-staged follicles. Reproduction, Fertility and Development. 21. Rodrigues, J. K., et al. (2015). Effect of hormonal supplementation on in vitro maturation of caprine oocytes. Theriogenology, 83(1), 124-130. 22. SAS. (2018). Statistical Analysis System, User's Guide. Statistical. Version 9.6th ed. SAS. Inst. Inc. Cary. N.C. USA. 23. Foster, D. L., & Hileman, S. M. (2015). Puberty in sheep. In Knobil and Neill's Physiology of Reproduction (pp. 1257–1306). Elsevier. https://doi.org/10.1016/B978-0-12-397175-3.00025-2 24. McNatty, K. P., et al. (2002). Ovarian follicular development and function: the role of FSH and LH in regulating the expression of steroidogenic enzymes. Reproduction, 123(5), 743–751. https://doi.org/10.1530/ rep.0.1230743 25. Scaramuzzi, R. J., et al. (2006). A review of metabolic and endocrine factors influencing the reproductive system in sheep. Reproduction Nutrition Development, 46(4), 339–354. https://doi.org/10.1051/rnd:2006021 26. Notter, D. R. (2008). Genetic aspects of reproduction in sheep. Reproduction in Domestic Animals, 43(Suppl. 2), 122–128. https://doi.org/10.1111/j.1439-0531.2008.01150.x 27. Gilchrist, R. B., Lane, M., & Thompson, J. G. (2008). Oocyte-secreted factors: regulators of cumulus cell function and oocyte quality. Human Reproduction Update, 14(2), 159–177. https://doi.org/10.1093/humupd/ dmm040 28. Eppig, J. J. (1991). Intercommunication between oocytes and companion somatic cells in the ovary. BioEssays, 13(11), 569–574. https://doi.org/10.1002/bies.950131102 29. Sugiura, K., & Eppig, J. J. (2005). Control of metabolic cooperativity between oocytes and their companion granulosa cells. Reproduction, Fertility and Development, 17(7), 667–674. https://doi.org/10.1071/RD05068 30. Hillier, S.G. (2001). Gonadotropic control of ovarian follicular growth and development. Mol Cell Endocrinol, 179(1-2), 39–46. https://doi.org/10.1016/S0303-7207(01)00473-2 31. Filicori, M., et al. (2002). Luteinizing hormone activity in menotropins optimizes folliculogenesis. J Clin Endocrinol Metab, 87(3), 1156–1161. https://doi.org/10.1210/jcem.87.3.8275 32. Fauser, B.C., et al. (2011). Women's health aspects of PCOS: 3rd PCOS Consensus. Fertil Steril, 97(1), 28–38.e25. https://doi.org/10.1016/j.fertnstert.2011.09.024 33. Simoni, M., Gromoll, J., & Nieschlag, E. (2002). The FSH receptor: biochemistry, molecular biology, physiology, and pathophysiology. Endocrine Reviews, 23(6), 747–773. https://doi.org/10.1210/er.2001-0023