Estrus response and fertility of Menz and crossbred ewes to single prostaglandin injection protocol
- 215 Downloads
Natural lambing in sheep in Ethiopia occurs throughout the year in a scattered manner negatively affecting survival and growth rates of the lambs born during the unfavorable season of the year. Thus, controlling the time of mating artificially using exogenous source of hormones is considered as one of the ways to mitigated problems related to haphazard lambing. To this end, an experiment was conducted to evaluate efficacy of prostaglandin-based estrus synchronization protocol in local and crossbred ewes. A total of 160 ewes (80 local and 80 crossbreds) which lambed at least once and aged 3–5 years were used. Lutalyse® (dinoprost tromethamine sterile solution equivalent to 5 mg dinoprost per ml) and its analog, Synchromate® (cloprostenol sodium equivalent to 0.250 mg cloprostenol per ml), were tested at different doses. The treatments used were intramuscular injection of (1) 2.50 ml of Lutalyse® (12.5 mg dinoprost tromethamine), (2) 2 ml of Lutalyse® (10.0 mg dinoprost tromethamine), (3) 1 ml of Synchromate® (0.25 mg of cloprostenol Sodium), and (4) 0.8 ml of Synchromate® (0.20 mg of cloprostenol Sodium). Forty ewes (20 local and 20 crossbreds) were allocated per treatment. Following injection of the respective hormones, rams of known fertility were introduced into the flock for the duration of 96 h at the ratio of one ram to 10 ewes. All estrus synchronization protocols except treatment 4 (0.8 ml of Synchromate®) induced estrus (heat) in majority (55–65 %) of local and crossbred ewes within 96 h post-hormone injection. The time interval from hormone administration to onset of estrus was also more or less similar for all treatment groups except for treatment group 4 which showed heat quicker. The highest lambing rate was recorded in local ewes (84.62 % (11/13) treated with 2.5 ml of Lutalyse®, whereas the least was obtained in crossbreds (33.33 % (3/9) treated with 0.8 ml Synchromate®. In conclusion, even though 2.5 ml and 2 ml of Lutalyse® or 1 ml of Synchromate® were able to induce heat in majority of local and crossbred ewes, the highest lambing percentage was obtained from ewes treated with 2.5 ml of Lutalyse®. Therefore, the use of 2.5 ml Lutalyse® is recommended to synchronize estrus in local and crossbred ewes under Ethiopian smallholder sheep production system for the benefit of improved lambing rate.
KeywordsCrossbred Lambing Lutalyse® Estrus Synchromate® Synchronization
The authors acknowledge the Amhara Regional State Livestock Development and Promotion Agency (ALDPA) for allowing ewes for the experiment and the staff of Debre Berhan sheep breeding and multiplication center for their assistance during implementation of the experiment. Department of Foreign Affairs, Trade and Development of Canada is acknowledged for sponsoring the study.
Compliance with ethical standards
The manuscript does not contain clinical studies or patient data.
Conflict of interest
The authors declare that they have no competing interests.
- CSA (Central statistical Authority), 2013. Agricultural sample survey on Livestock and Livestock characteristics, Central Statistical Agency, Volume II, statistical bulletin no. 570, Addis Ababa, EthiopiaGoogle Scholar
- DBSBMC (Debre Berhan Sheep Breeding and Multiplication Center), 2006. Synthesis report, Office of Agriculture and Rural Development, Amhara Region, EthiopiaGoogle Scholar
- EL-Sherry, Taymour, M, Waleed, S., Gamal, B. M. and Salwa I. W., 2013. Effect of dinoprost and cloprostenol on serum nitric oxide and corpus luteum blood flow during luteolysis in ewes, Theriogenology, 80 (5):513–518Google Scholar
- Fierro, S., Gil, J., Viñoles, C. and Olivera-Muzante, J., 2013. The use of prostaglandins in controlling estrous cycle of the ewe: a review, Theriogenology, 78, 1796–1799Google Scholar
- Gatti, M. and Ungerfeld, R., 2012. Intravaginal sponges to synchronize estrus decrease sexual attractiveness in ewes, Theriogenology, 7, 1232–1238Google Scholar
- Hacket, A.J. and Robertson, H.A., 1980. Effect of dose an time of injection of Prostaglandin F2 alpha in cycling ewes, Theriogenology, 13(5): 347–351Google Scholar
- Hoppe, KF. and Slyter, A.L., 1989 Effects of prostaglandin F2 alpha dosage on synchronizing ovine estrus using a modified single injection regimen, Theriogenology, 31, 1191–1200Google Scholar
- Kalyan, D.E, Davendra, K., Debabrata, S., Rajiv, G. and Syed, M.K.N., 2015. Estrus synchronization and fixed-time artificial insemination in sheep under field conditions of a semi-arid tropical region, Tropical Animal Health and Production, 47,467-472Google Scholar
- Letelier, C.A., Contreras-Solis, I., García-Fernández, R.A., Sánchez, M.A., García-Palencia, p., Sánchez, B., Ariznavarret, C. Tresguerres, J.A.F., Flores, J.M. and Gonzalez-Bulnes, A., 211. Effects of oestrus induction with progestagens or prostaglandin analogues on ovarian and pituitary function in sheep, Animal Reproduction Science, 126, 61–69Google Scholar
- Mahboub, H., Abd El-Razek, E. A., Helal, M. A.Y. and Mustafa, I., 2013. Effects of Breed and Prostaglandin Administration on Reproductive Performance and Profitability of Egyptian Ewes, Theriogenology, 3, 95–106Google Scholar
- Martinez, M.F., McLeod, B., Tattersfield, G., Smaill, B., Quirke, L.D. and Juengel, J.L., 2015. Successful induction of oestrus, ovulation and pregnancy in adult ewes and ewe lambs out of the breeding season using a GnRH + progesterone oestrus synchronisation protocol, Animal Reproduction Science, 155, 28–35PubMedCrossRefGoogle Scholar
- Moreira, F. and Hammon, D. 2012. Lutalyse® and cloprostenol: Clearing up misconceptions: Technical bulletin, Zoeis, 12p.Google Scholar
- SAS (statistical Analysis System), 1999. Statistical Methods. SAS Institute Inc., Cary, North CarolinaGoogle Scholar
- Solomon, G., Hans, K., Jack, J., Olivier, H., Johan, A.M. and Van, A., 2008. Conservation priorities for Ethiopian sheep breeds combining threat status breed merits and contributions to genetic diversity, Genetics Selection Evolution, 40, 433–447Google Scholar
- Tibbo, M., 2006. Productivity and health of indigenous sheep breeds and crossbreds in the central Ethiopian highlands PhD theses, University of Uppsala, Sweden, http://pub.epsilon.slu.se/1142/1/Markos_Tibbo_corrected.pdf Google Scholar
- Zeleke, M., 2009. Effect of time of Pregnant Mare Serum Gonadotrophin Administration on Oestrus Synchronization Efficiency and Fertility in Blackhead Ogaden Ewes, Ethiopian Journal of Animal Production, 9, 135–145Google Scholar
- Zohara, B.F., Azizunnesa, Md., Faruk Islam, Md., Golam, S.A. and Farida, Y.B., 2014. Comparison of Estrus Synchronization by PGF2α and Progestagen Sponge with PMSG in Indigenous Ewes in Banglades, GSTF International Journal of Veterinary Science, 1, 27–37Google Scholar