Comparison of Pregnancy Rates after Short - Term and Long -Term Synchronization Protocol in Ewes- Pilot Study

Öz

The objective of the study was to compare the pregnancy rates after short-term and long-term synchroniza-tion protocol in Kivircik ewes. Ewes (n=54) were randomly divided into two synchronization groups as ST (short-term; n=27) or LT (long-term, n=27). Intravaginal sponge was inserted on the same day (D0) in both groups. It was removed at 7 days (D7) in the ST group and 13 days (D13) in the LT group. All ewes received 450 IU eCG and 75 μg d-cloprostenol at the time of sponge removal. The characteristics of vaginal discharge were evaluated following sponge withdrawal. For both protocols, 5 fertile rams per 27 ewes were used for natural mating following sponge removal. The overall estrous response and pregnancy rate were 88.9% and 64.8%, respectively. Following the synchronization, the overall estrous response (94.7% vs. 85.7%, respectively) and pregnancy rate (63.1% vs. 65.7%, respectively) were similar in both multiparous and nulliparous ewes. Although the short-term protocol reduced the rate of severe vaginitis from 48.1% to 25.9%, pregnancy rates were not different in both synchronization protocols. Nulliparous ewes had a higher rate (48.6% vs. 15.8%) of severe vaginal discharge than multiparous ewes. However, the alteration of the vagi-nal discharge severity depending on parity did not affect the overall pregnancy rate after the short-term (66.7%) and long-term (63.0%) protocols. Therefore, the long-term and short-term protocol can be used in both nulliparous and multiparous ewes in small flocks.

Anahtar Kelimeler

• Ewe
• fertility
• short-term
• synchronization
• vaginitis

Koyunlarda Kısa-Süreli ve Uzun-Süreli Senkronizasyon Protokolü Sonrası Gebelik Oranlarının Karşılaştırılması- Ön Çalışma

Öz

Bu çalışmanın amacı Kıvırcık koyunlarda kısa süreli ve uzun süreli senkronizasyon protokolü sonrası gebelik oranlarını karşılaştırmaktı. Koyunlar (n=54) KS (kısa süreli; n=27) ve US (uzun süreli; n=27) olmak üzere rastgele iki senkronizasyon grubuna ayrıldı. Her iki gruba da aynı gün intravaginal sünger takıldı. KS grubunda 7. günde ve US grubunda 13. günde intravaginal sünger çıkartıldı. Süngerin çıkarılmasıyla koyunlara 450 IU eCG ve 75 μg d-cloprostenol uygulandı. Süngerin çıkartılmasını takiben vaginal akıntının karakteri değerlendirildi. Her iki protocol için de süngerin çıkartılmasını takiben doğal çiftleşme için 27 baş koyun başına 5 fertil koç kullanıldı. Toplam östrus yanıtı ve gebelik oranı sırasıyla %88.9 ve %64.8 idi. Senkronizasyonu takiben multipar ve nullipar koyunlarda toplam östrus yanıtı (sırasıyla %94.7’ye karşı %85.7), ve gebelik oranı (sırasıyla %63.1’e karşı %65.7) benzerdi. Kısa süreli protokol şiddetli vaginitis oranını %48.1’den %25.9’a azaltmasına rağmen, her iki senkronizasyon protokolündeki tüm vaginal akıntı skorlarına ait gebelik oranları farklı değildi. Nullipar koyunlar, multipar koyunlara göre daha yüksek oranda (%48.6'ya karşı %15.8) şiddetli vaginal akıntıya sahipti. Ancak vajinal akıntı şiddetinin pariteye bağlı olarak değişmesi, kısa süreli (%66.7) ve uzun süreli (%63.0) protokol sonrası toplam gebelik oranını etkilemedi. Dolayısıyla küçük sürülerde uzun süreli ve kısa süreli protokol hem nullipar hem de multipar koyunlarda kullanılabilir.

Anahtar Kelimeler

• Fertilite
• kısa-süreli
• koyun
• senkronizasyon
• vaginitis

Kaynakça

1. Abecia J, Forcada F, González-bulnes A. Hormonal control of reproduction in small ruminants. Anim Reprod Sci 2012; 130(3-4): 173-9.
2. Allison AJ, Davis GH. Effects of number of ewes joined per ram, age of ewe, and paddock size. New Zeal J Exp Agric 1976; 4(3): 259-67.
3. Ataman MB, Aköz M, Akman O. Induction of synchro-nized oestrus in akkaraman cross-bred ewes dur-ing breeding and anestrus seasons: The use of short-term and long-term progesterone treatments. Rev Med Vet 2006;157(5): 257-60.
4. Biehl MV, de Ferraz Junior MVC, Barroso JPR, Susin I, Ferreira EM, Polizel DM, Pires AV. The reused progesterone device has the same effect on short or long estrus synchronization protocols in tropical sheep. Trop Anim Health Prod 2019; 51(6): 1545-9.
5. Blaschi W, Lunardelli PA, Marinho LSR, Max MC, Santos GMG, Silva-Santos KC, Melo-Sterza FA, Baldassarre H, Rigo TR, Seneda MM. Effects of progestagen exposure duration on estrus synchro-nization and conception rates of crossbreed ewes undergoing fixed time artificial insemination. J Vet Sci 2014; 15(3): 433-7.
6. Corner RA, Mulvaney FJ, Morris ST, West DM, Morel PCH, Kenyon PR. A comparison of the reproductive performance of ewe lambs and mature ewes. Small Rumin Res 2013; 114(1): 126-33.
7. Evans ACO, Duffy P, Crosby TF, Hawken PAR, Bo-land MP, Beard AP. Effect of ram exposure at the end of progestagen treatment on estrus synchronisation and fertility during the breeding season in ewes. Anim Reprod Sci 2004; 84(3-4): 349-58.
8. Koyuncu M, Altincekic SO. Effects of progestagen and pmsg on estrous synchronization and fertility in kivircik ewes during natural breeding season. Asian-Australas J Anim Sci 2010; 23(3): 308-11.

9. Manes J, Fiorentino MA, Martino SS, Ungerfeld R. Changes in the vaginal microbiota in ewes after insertion of intravaginal sponges at different stages of the oestrous cycle. Livest Sci 2018; 208: 55-9.
10. Manes J, Ríos G, Andrea M, Ungerfeld R. Vaginal mucus from ewes treated with progestogen sponges affects quality of ram spermatozoa. Theriogenology 2016; 85(5): 856-61.
11. Martinez-Ros P, Lozano M, Hernandez F, Tirado A, Rios-Abellan A, López-Mendoza MC, Gonzalez-Bulnes A. Intravaginal device-type and treatment-length for ovine estrus synchronization modify vagi-nal mucus and microbiota and affect fertility. Animals 2018; 8(12): 1-8.
12. Menchaca A, dos Santos-Neto PC, Cuadro F, Souza-Neves M, Crispo M. From reproductive technologies to genome editing in small ruminants: An embryo’s journey. Anim Reprod 2018; 15: 984-95.
13. Özyurtlu N, Ay SS, Küçükaslan İ, Güngör Ö, Aslan S. Effect of subsequent two short-term, short-term, and long-term progestagen treatments on fertility of Awassi ewes out of the breeding season. Ankara Üniv Vet Fak Derg 2011; 58(2): 105-9.
14. Ungerfeld R, Rubianes E. Effectiveness of short-term progestogen primings for the induction of fertile oestrus with eCG in ewes during late seasonal anoestrus. Anim Sci 1999; 68: 349-53.
15. Ungerfeld R, Rubianes E. Short term primings with different progestogen intravaginal devices (MAP, FGA and CIDR) for eCG-estrous induction in anestrus ewes. Small Rumin Res 2002; 46(1): 63-6.
16. Ungerfeld R. Reproductive response of mature and nulliparous yearling ewes to the ram effect during the non-breeding season. Small Rumin Res 2016; 140: 37-9.
17. Ustuner B, Gunay U, Nur Z, Ustuner H. Effects of long and short-term progestagen treatments combined with PMSG on oestrus synchronization and fertility in Awassi ewes during the breeding season. Acta Vet Brno 2007; 76: 391-7.
18. Vinoles C, Forsberg M, Banchero G, Rubianes E. Effect of long term and short term progestagen treatment on follicular development and pregnancy rate in cyclic ewes. Theriogenology 2001; 55(4): 993-1004.
19. Vinoles C, Meikle A, Forsberg M, Rubianes E. The effect of subluteal levels of exogenous progester-one on follicular dynamics and endocrine patterns during the early luteal phase of the ewe. Theriogenology 1999; 51(7): 1351-61.