The Effect of Second Prostaglandin F2α Application with the Presynchronization Protocol on Fertility in Simmental Cows

Öz

The objective of the study was to evaluate the effect of an additional PGF2α injection 24 hours after the first PGF2α in the timed AI Ovsynch protocol on the pregnancy/artificial insemination (P/AI) rate of Simmental cows presynchronized with PG-3-G. The study was conducted on a commercial farm with 103, lactating Simmental cows. Animals were randomly divided into two groups (1) PG-3-G Group (n=56): PGF2α on day 0; GnRH on day 3; Ovsynch initiation after on day 10. (2) PG-3-PG Group (n=47): Second PGF2αaddition 24 hours apart before timed AI to PG-3-G protocol. Parity, milk yield, and days in milk (DIM) were compared between the synchronization protocols. The pregnancy rates in the postpartum first and ≥2 TAI were similar between groups (p=0.462 and p=0.566, respectively). There were no statistical differences in the P/AI rates between groups 51.78% (29/56) and 51.06% (27/47), respectively. Multiparous cows revealed numerically higher pregnancy rates than the primiparous cows. However, P/AI results did not differ between groups (p=0.942). The mean preovulatory follicle diameter was 1.71±0.15 cm in the PG-3-G group, and 1.79±0.15 cm in the PG-3-PG group and the difference between groups was significant (p=0.047). In conclusion, administration of a second PGF2α injection to the protocol improved the P/AI numerically in multiparous cows, and preovulatory follicle size. Nevertheless, those findings need to be evaluated by conductinga larger study with a larger sample size.

Anahtar Kelimeler

• Fertility
• GnRH
• Presynchronization
• Second PGF2α

Destekleyen Kurum

This study did not receive any funding.

Etik Beyan

All animal experimental procedures were approved by the Experimental Animal Local Ethics Committee of Afyon Kocatepe University (approval number: 2023/49533702/94).

Teşekkür

The authors express their gratitude to Ballıpınar Farm for his valuable support in this study.

Simental İneklerde Presenkronizasyon Protokolünde İkinci Prostaglandin F2α Uygulamasının Fertiliteye Etkisi

Öz

Bu çalışmanın amacı PG-3-G protokolü ile presenkronizasyon protokolü uygulanan Simental ırkı ineklerde izleyen Ovsynch protokolünde suni tohumlama öncesi uygulanan PGF2α’dan 24 saat sonra ikinci PGF2α enjeksiyonunun gebelik/suni tohumlama (G/ST) oranına etkisinin değerlendirilmesidir. Çalışma ticari bir çiftlikte yetiştirilen 103 adet sağmal Simental inekte gerçekleştirildi. Hayvanlar rastlantısal olarak iki gruba ayrıldı (1) PG-3-G Grubu(n=56): 0. gün PGF2α; 3. gün GnRH; 10. gün standart Ovsynch protokolü başlangıcı. (2) PG-3-PG Grubu(n=47): PG-3-G grubuna ilave olarak suni tohumlamadan önceki PGF2α’dan 24 saat sonra 2. PGF2α enjeksiyonu. Senkronizasyon grupları arasında parite, süt verimi ve sağılan gün sayısı (SGS) da karşılaştırıldı. Postpartum ilk ve ≥2. ST’da gruplar arası gebelik oranları bakımından fark bulunmadı (p=0.462 and p=0.566, respectively). Gruplar arasında G/ST oranları açısından istatistiksel fark tespit edilmedi, sırasıyla %51.78 (29/56) ve %51.06 (27/47). Multipar ineklerde gebelik oranları primipar ineklere göre daha yüksek olma eğilimi saptandı, ancak gruplar arasında fark önemsizdi (p=0.942). PG-3-G grubunda ortalama preovulatör folikül çapı 1.71±0.15 cm bulunurken, PG-3-PG grubunda 1.79±0.15 tespit edildi; gruplar arasındaki fark anlamlı bulundu (p=0.047). Sonuç olarak, PG-3-G protokolüne ikinci PGF2α enjeksiyonunun eklenmesinin multipar ineklerde G/ST oranının ve preovulatör folikül büyüklüğünün artırılmasına katkısı olduğu belirlendi. Bununla birlikte, çalışmada ortaya konan bulguların daha büyük örnek sayısı ile ayrıntılı olarak araştırılması gerektiği kanaatine varıldı.

Anahtar Kelimeler

• Fertilite
• GnRH
• İkinci PGF2α
• Presenkronizasyon

Destekleyen Kurum

Bu çalışma herhangi bir fon desteği almadı.

Etik Beyan

Tüm hayvan deney prosedürleri, Afyon Kocatepe Üniversitesi Yerel Deneysel Hayvan Etik Kurulu tarafından onaylanmıştır (onay numarası: 2023/49533702/94).

Teşekkür

Yazarlar, bu çalışmadaki değerli desteklerinden dolayı Ballıpınar Çiftliği'ne teşekkürlerini sunarlar.

Kaynakça

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