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

Abstract

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.

Keywords

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

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

Abstract

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.

Keywords

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

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