You are here

Clinical and laboratory prognostic indicators for fertility in sheep

With the use of technology of artificial insemination in sheep farms are not yet defined criteria for assessing the full value of the preparation of females for insemination, and hence – the possibility of prediction and correction of their fertilization, which prevents the rational use of cryopreserved semen and ensuring the maximum reception of the offspring. We have proved the prognostic importance of fertilization of the morphofunctional state of the vulva and the vagina and the quality of mucus in sheep breeds during estrus. The material of the study was 327 sheep of ascanian breeding, which during the sexual intercourse before insemination examined the vulva, vagina and evaluated the estrus slime (number, color, consistency, presence of impurities, elasticity, electrical resistance, type of crystallization, protein content). The results of ultrasound diagnosis of pregnancy were determined by the fertility of sheep with different integral compositions of clinical and laboratory parameters.

It has been established that in sheep, in which fertility in the first sexual cycle reached 65.1%, most often found a pink, moderately edematous vulva with clear mucus. In females with pale mucous membrane and insignificant amount of mucus, the effectiveness of inseminates declined to 53.3-58.0%. In a significant amount of estral mucus, the proportion of infertile animals increased twofold. At the same time, the selection of liquid, but cloudy, or thick mucus is a sign of an unfavorable prognosis, in which fertility decreases by 1.8-2.1 times (p <0.001). Dense, white, paste-like isolates were observed in a small number of sheep, mostly bright at the beginning of the anestral season. Low fertility in the first sexual hunting (35.5%) and a high multiplicity of repeated inseminations (29.0%) indicate that sheep with thick estral slime are only beginning to enter the sexual season, and this quality of secrecy indicates an inadequate estrogenization of the body.

It was also found that in the infertile sheep during sexual hunting, the protein content of cervical mucus was 4.8 times higher, and the elasticity of mucus was reduced by 2.9 times. The most prevalent was the prognosis of average fertilization (53.3-58.0%), which was recorded in 62.9% of experimental sheep. The prognosis of high fertilization, which resulted in 62.5-65.1% of oseminins, was found in 27.8% of females. At the same time, the number of females with a fertility forecast at 40% was only 3.1%, and the prevalence of an unfavorable prognosis, in which fertility was the smallest (30.0-35.5%), reached 6.2%.

Key words: sheep, askanian breeding, estrus, fertility prognosis, estral mucus, vulva, vagina, artificial insemination.

1. Zhulinska, O.S., Drozd, S.L., Mohylnytska, S.V. (2016). Analiz pokaznykiv vidtvorennia v ovets askaniiskoi selektsii [Analysis of reproduction rates in sheep Askanian breeding]. Biolohiia tvaryn [Biology of animals]. Issue 18, no. 3, pp. 36–45.

2. Amr, A. Gabr., Nazem, A. Shalaby., Mohamed, E. Ahmed. (2016). Effect of Ewe Born Type, Growth Rate and Weight at Conception on the Ewe Subsequent Productivity of Rahmani Sheep. Asian Journal of Animal and Veterinary Advances. pp. 732–736.

3. Gardner, D.S., Buttery, P.J., Danieland, Z., Symonds, M.E. (2007). Factors affecting birth weight in sheep: Maternal environment. Reproduction. pp. 297–307.

4. Notter, D.R. (2008). Genetic aspects of reproduction in sheep. Reproduction Domestic Animal. pp. 122–128.

5. Earle, E., McHugh, N., Boland, T.M., Creighton, P. (2017). Effect of ewe prolificacy potential and stocking rate on ewe and lamb performance in a grass-based lamb production system. J. Anim Sci. Vol. 95(1), pp. 154–164.

6. Freetly, H.C., Leymaster, K.A. (2004).  Relationship between litter birth weight and litter size in six breeds of sheep. J. Animal Science. Issue 82(2), pp. 612–618.

7. Douhard, F., Jopson, N.B., Friggens, N.C., Amer, P.R. (2016). Effects of the level of early productivity on the lifespan of ewes in contrasting flock environments. Animal. pp. 2034–2042.

8. Koshevoi, V.P., Skliarov, P.M., Naumenko, S.V. (2011). Problemy vidtvorennia ovets i kiz ta shliakhy yikh vyrishennia [Problems of reproduction of sheep and goats and ways to solve them]. Kh.D. Hamaliia, 467 p.

9. Parkinson, T. (2009). Artificial insemination of ewes. In: Noakes, D.E., Parkinson, T.J., England, G.C.W. (eds) Veterinary Reproduction and Obstetrics. 9th edition. Saunders-Elsevier, London, UK. pp. 765–808.

10. Bolotov, Yu.I. (2010) Udoskonalennja tehnologichnyh pryjomiv pidvyshhennja spermoprodukcii' baraniv-plidnykiv i vidtvorjuval'nyh jakostej vivcematok riznogo naprjamku produktyvnosti: avtoref. dys.  kand. s.-g. nauk: 06.02.04. [Perfection of technological methods of increase of semen production of sheep-breeders and reproductive qualities of ewes of different direction of productivity: the abstract of the dissertation of the candidate of agricultural sciences: 06.02.04.]. Kherson, 18 p.

11. The State of the Worlds Animal Genetic Resources for Food and Agriculture. Edited by Barbara Rischkowsky and Dafydd Pilling. FAO. Rome, 2007. 511 p.

12. Banerjee Ramanuj, Mandal Prabhat Kumar, Pal Uttam Kumar, Ray Kunal. (2010). Productivity and Genetic Potential of Garole Sheep of India – A Review. Asian Journal of Animal Sciences. Vol. 4, pp. 170–189.

13. Sukharlёv, V.A., Yakovlev, K.Y. (2011). Ovcy Ukrainy [Sheep of Ukraine]. Kharkov. Espada, 352 p.

14. Rosa, H.J.D., Bryant, M.J. (2003). Seasonality of reproduction in sheep. Review. Small Ruminant Research. Vol. 48, pp. 155–171.

15. Lobachova, I.V. (2016). Morfolohiia yaiechnykiv ovets u rizni misiatsi roku [Morphology of ovary sheep in different months of the year]. Biolohiia tvaryn [Biology of animals]. Issue 18, no. 1, pp. 77–86.

16. David, O. Norris., James, A. Carr. (2013). Vertebrate Endocrinology (Fifth Edition). Chapter 10 – The Endocrino-logy of Mammalian Reproduction.  3 p.

17. Nezhdanov, A.H. (2008). Bolezni organov razmnozhenija u krupnogo rogatogo skota v svete sovremennyh dostizhenij reproduktivnoj jendokrinologii i patobiohimii [Diseases of the reproductive organs in cattle in the light of modern advances in reproductive endocrinology and pathobiochemistry]. Sovremennye problemy diagnostiki, lechenijai profilaktiki infekcionnyh boleznej zhivotnyh i ptic [Modern problems of diagnosis, treatment and prevention of infectious diseases of animals and birds]. Yekaterinburg, Issue. 2, pp. 350–364.

18. Richards, J.A.S., Pangas, S.A. (2010). The ovary: Basic biology and clinical implications.  J. Clincal Investigation. Vol. 120, pp. 963–972.

19. Manju, Yadav. (2008). Mammalian Endocrinology. Encyclopedia of endocrinology, E. 2. Lecture Department of Zoology M.M.H. College. Chaziabad (U.P. India) Discovery Publishing House PVT.LTD. New Delhi –110002. 384 p.

20. Zohara, B.F., Azizunnesa, A., Islam, M.F., Alam, M. G., Bari, F. Y. (2014). Exfoliative vaginal cytology and serum progesterone during the estrous cycle of indigenous ewes in Bangladesh. Journal of Embryo Transfer. Vol. 29 (2), pp. 183–18.

21. Salve, R.R., Ingole, S.D., Nagvekar, A.S., Bharucha, S.V., Dagli, N.R. (2016). Pregnancy Associated Protein and Progesterone Concentrations During Early Pregnancy in Sirohi Goats. Small Ruminant Research. Vol. 141, pp. 45–47. 

22. Christensen, A.C., Haresign, W., Khalid, M. (2014). Progesterone exposure of seasonally anoestrous ewes alters the expression of angiogenic growth factors in preovulatory follicles. Theriogenology. Vol. 81, pp. 358–367.

23. Perry, G.A., Perry, B.L. (2009). Effect of the timing of controlled internal drug-releasingdevice inception of the gonadotropin-releasing hormone-induced luteinizing hormone surge and ovulatory response. J. Animal Science. Vol. 87, pp. 3983–3990.

24. David, O. Norris., James, A. Carr. (2013). Vertebrate Endocrinology (Fifth Edition). Chapter 10 – The Endocrinology of Mammalian Reproduction. pp. 317–374.

25. Noel, B., Bister, J.L., Paquay, R. (1993). Ovarian follicular dynamics in Suffolk ewes at different periods of the year. Journal of Reproduction and Fertility. Vol. 99, pp. 695–700.

26. Lewis, A.W., Berardinelli, J.G. (2001). Gross anatomical and histomorphometric characteristics of the oviduct and uterus during the pubertal transition in sheep. J. Animal Scie. Vol. 79(1), pp. 167–175.

27. Kekan, P.M., Ingole, S.D., Sirsat, S.D., Bharucha, S.V., Kharde, S.D., Nagvekar, A.S. (2017). The role of pheromones in farm animals – A review. Agricultural Reviews. Vol. 38(2), pp. 83–93.

28. Mahmoud, G.B.A. (2013). Physical and chemical properties of ewes cervical mucus during normal estrus and estrus induced by intravaginal sponges. Egyptian J. Animal Production. Vol. 50 (1), pp. 7–12.

29. Kharuta, H.H., Volkov, S.S. Lototskyi, V.V. (2009). Stymuljacija i synhronizacija statevoi' cyklichnosti u koriv ta metody pidvyshhennja zaplidnenosti: metod. rekom. [Stimulation and synchronization of sexual cyclicity in cows and methods of increasing fertilization: guidelines]. Bila Tserkva, 21 p.

30. Vlasenko, S.A. (2010). Poshyrenist hinekolohichnykh khvorob ta efektyvnist hormonalnoi stymuliatsii i synkhronizatsii stadii zbudzhennia statevoho tsyklu u koriv z hniino-nekrotychnymy urazhenniamy v diliantsi paltsiv [The prevalence of gynecological diseases and the effectiveness of hormonal stimulation and synchronization of the stage of excitation of the sexual cycle in cows with purulent-necrotic lesions in the area of fingers]. Biolohiia tvaryn [Biology of animals]. Issue. 12,  no. 1, pp. 184–191.

PDF icon vlasenko_1_2019.pdf6.48 MB