Influence of annual photoperiod changes on ovarian activity of Sanjabi ewes

Document Type : Research Paper

Author

Member of the faculty of Kermanshah Agricultural and Natural Resources Research and Education Center

Abstract

This experiment was conducted to identify the annual cycle of ovarian activities and to determine the relationship between ovary size and ovarian activity in sheep. For this purpose, at least five pairs of Sanjabi ewes ovaries were collected each week during the one year of study and after weighing of each ovary, the number and diameter of visible follicles at the ovary surface, the weight and volume of the corpus luteum and the number of ovaries containing corpus luteum were recorded. Data were analyzed using general linear model test. The results showed that there was no significant difference between right and left ovaries of ewes in terms of mean weight, relative frequency of large, medium and small size follicles and the relative frequency of the number of ovaries containing the corpus luteum. There was a significant positive correlation between ovary weight of ewes and their ovarian activities. The highest relative frequency of ovulation in right ovaries were observed in December and in left ovaries were observed in June and December (p < 0.05). The lowest relative frequency of ovulation in the right ovarieswere observed in April, June, August and March and in the left ovaries were observed in April, September and March (p < 0.05). Based on the results, the Sanjabi ewes in Kermanshah region have some reproductive activity in spring which indicates the return of a temporary ovarian activity in this season and it can lead to out-of-season pregnancies.

Keywords

References

احمدی، م. ر.، روزی طلب، ح.(1379). بررسی کشتارگاهی فعالیت تولید مثل میش در منطقه فارس. مجله پژوهش و سازندگی:46، 128-126.
صادقی پناه، ح.(1384). اثرات سطح و منبع چربی جیره بر بازده تولید مثل، نرخ تخمک ریزی، استروئیدسازی و سوخت و ساز تخمدان میش. رساله برای دریافت درجه دکتری تخصصی تغذیه دام. دانشکده کشاورزی. دانشگاه تهران.
عباسی، م.، کریمی، ح. وقارزی، ا. (1385). مطالعه بیومتری و هیستومتری تخمدان گوسفند لری. مجله دامپزشکی ایران 2: 95-101.
فراستی، س.(1390). استفاده از پروژسترون و eCG به منظور بالا بردن راندمان تولید مثلی در گله های گوسفند استان. گزارش نهایی پروژه تحقیقاتی- ترویجی. مدیریت هماهنگی ترویج کشاورزی استان کرمانشاه.
مرکز آمار ایران (1396). نتایج تفضیلی آمارگیری از دامداری­های کشور. سازمان برنامه و بودجه کشور. ریاست جمهوری. قابل دسترس در https://www.amar.org.ir/Portals/0/News/1396/a-dams96.pdf.
نعمت الهی، ا. و  ایزدی، غ.  ع. (1384). بررسی کشتارگاهی فعالیت تولید مثلی میش های ماکویی. مجموعه مقالات دومین سمینار پژوهشی گوسفند و بز کشور.
Abecia, J.A., Chemineau, P., Gómez, A., Palacios, C., Keller, M. and Delgadillo, J.A. (2012). Exposure to photoperiod-melatonin-induced, sexually-activated rams after weaning advances the resumption of sexual activity in post-partum Mediterranean ewes lambing in January. Veterinary Sciences, 4(1), 4. doi:10.3390/vetsci4010004.
Arroyo, J., Sánchez-Hernández, N.J., Ávila-Serrano, N.Y., Camacho-Escobar, M.A. and Rodríguez-De-La-Torre, M. (2016). Reproductive seasonality in creole hair sheep in the tropic. Tropical Animal Health and Production, 48(1): 219–222. https://doi.org/10.1007/s11250-015-0927-z.
Arthur, G.H., Noakes, D.E. and Pearson, H. (1989). Normal reproductive function. In: Veterinary Reproduction and Obstetrics. Editor: Saunders WB. London, Balliere Tindall pp. 22-24.
Bartlewski, P.M., Beard, A.P., Cook, S.J. and Rawlings, N.C. (1998). Ovarian follicular dynamics during anoestrus in ewes. Journal of Reproduction and Fertility. 113: 275-285.
Cahill, L.P. (1981). Folliculaogenesis in the sheep as influenced by breed, season and oestrous cycle. Journal of Reproduction and Fertility. (Suppl) 30: 135-142.
Cushman, R.A., Allan, M.F., Kuehn, L.A., Snelling, W.M., Cupp, A.S.  and Freetly, H.C. (2009). Evaluation of antral follicle count and ovarian morphology in crossbred beef cows: Investigation of influence of stage of the estrous cycle, age, and birth weight. Journal of Animal Sciences.87:1971-1980.
Forcada, F. and Abecia, J.A. (2006). The effect of nutrition on the seasonality of reproduction in ewes. Reproduction Nutrition and Development. 46: 355-365.
Forcada, F., Abecia, J.A. and Sierra, I. (1992). Seasonal changes in oestrous activity and ovulation rate in Rasa Aragonesa ewes maintained at two different body conditions levels. Small Ruminant Research. 8: 313-324.
Gómez-Brunet, A., López-Sebastian, A., Muñiz-Herrando, E. and Cabellos, B. (1992). Función lutealy secreción de LH durante el anoestro post-parto en ovejas Manchegas: Influencia de la época del parto y tipo de destete. Investigación Agraria. Producción y Sanidad Animales.7 (3): 169-183.
Gómez-Brunet, A., Santiago-Moreno, J., Toledano-Diaz, A. and López-Sebastián, A. (2012). Reproductive seasonality and its control in Spanish sheep and goats. Tropical and Subtropical Agroecosystems, 15(1).
Juengel, J.L. and Niswender, G.D. (1999). Molecular regulation of luteal progesterone synthesis in domestic ruminants. Journal of Reproduction and Fertility. (Suppl) 54: 193-205.
Lass, A. and Brinsden, P. (1999). The role of ovarian volume in reproductive medicine. Human Reproduction Update. 5: 256- 266.
López-Sebastián, A., Palacio, M., Gómez-Brunet, A. (1991). Techniques for the improvement of fertility and prolificacy of anoestrus ewes in Spain. FAO/IAEA. Isotope aided studies on sheep and goat production.1: 157-164.
Murasawa, M., Takahashi, T., Nishimoto, H., Yamamoto, S., Hamano, S. and Tetsuka, M. (2005). Relationship between ovarian weight and follicular population in heifers. Journal of Reproductionand Development. 51: 689- 693.
Noel, B., Bister, J.L. and Paquay, R. (1993). Ovarian follicular dynamics in Suffolk ewes at different periods of the year. Journal of Reproduction and Fertility. 99: 695-700.
Ortavant, R., Pelletier, J., Ravault, J.P., Thimonier, J. and Volland-Nail, P. (1985). Photoperiod: main proximal and distal factor of the circannual cycle of reproduction in farm mammals. Oxford Review of Reproductive Biology. 7: 306-345.
Santiago-Moreno, J., Gonzalez-Bulnes, A., Gómez-Brunet, A. and López-Sebastían, A. (2000). Effect of season on the resumption of postpartum cyclic ovarian activity in Mouflon (Ovis gmelini musimon) and Manchega sheep (Ovis aries). Small Ruminant Research. 36: 69-74.
Sefidbakht, N., Mostafavi, M.S. and Farid, A. (1977). Effect of season of lambing on postpartum ovulation conception and follicular development of four fat-tailed Iranian breeds of sheep. Journal of Animal Sciences. 45:305-310.
Thimonier, J., Terqui, M. and Chemineau, P. (1986). Conduite de la reproduction des petits ruminants dans les différents parties du monde. In: Proceedings of an International Symposium on the Use of Nuclear Techniques in Studies of Animal Production and Health in Different Environments, International Atomic Energy Agency, Vienna, pp 135-147.
Thimonier, J. and Mauléon, P. (1969). Variations saisonnières du comportement d´oestrus et des activités ovariennes et hypophysaires chez les ovins. Annales de Biologie Animale Biochimie, Biophysique. 9: 233-250.
Valls Ortiz, M. (1983). Frequent lambing of sheep flocks in Spain: Productivity and management consequences. Livestook Production Science.10: 49-58.
Wheeler, A.G. and Land, R.B. (1977). Seasonal variation in oestrus and ovarian activity of Finnish-andrace Tasmanian-Merino and Scottish-Blackface ewes. Animal Production. 24: 363-376.
Animal Sciences Journal
Volume 34, Issue 130
June 2021
Pages 25-38

Files

Share

How to cite

Statistics