Ozan BİLGEN, ERHAN ÖZENÇ

Postpartum farklı günlerdeki ineklere uygulanan Double-Ovsynch programının bazı reprodüktif parametrelere etkileri

Bu çalışmada postpartum farklı günlerde uygulamaya başlanan Double-Ovsynch protokolünün çeşitli fertilite parametreleri üzerine olan etkilerinin değerlendirilmesi amaçlanmıştır. Çalışma 51 adet Holstein ırkı inek üzerinde yürütüldü ve hayvanlar 4 gruba ayrıldı. Grup 1, grup 2 ve grup 3’ün her birinde bulunan 12 hayvan sırasıyla postpartum 25., 32. ve 39. günlerde bulunuyordu. Grup 4 kontrol grubu olarak değerlendirildi ve bu gruptaki hayvanlara (n=15) postpartum 40. güne kadar hiçbir uygulama yapılmadı, bu günden sonra östrus gösterenlere suni tohumlama işlemi uygulandı. Çalışma grubundaki ineklere ise 0. gün GnRH, 7. gün $PGF _{2\alpha}$, 10. gün GnRH, 17. gün GnRH ve 24. gün $PGF _{2\alpha}$ uygulandı. $PGF _{2\alpha}$uygulamasından sonraki 56. saatte GnRH uygulaması yapıldı ve bunu takiben 16-20. (ortalama 18. saatte) saatlerde suni tohumlama işlemi uygulandı. Çalışma gruplarında senkronizasyon oranları %66.67 ile %91.67 arasında değişirken, grup 2 ve grup 3’de yüksek oranda senkronizasyon gözlendi. Çalışma grubundaki hayvanlarda ilk suni tohumlama sırasında çok az oranda östrus belirtileri gözlendi (P

Anahtar Kelimeler:

eş zamanlama, GnRH, sığır, inek, süt sığırı, süt ineği, dişi döl verimi, kızgınlık, doğum sonrası dönem, gebelik oranları, prostaglandinler, üreme, üreme randımanı, dölverim performansı, üreme özellikleri

Effects of the Double-Ovsynch program on some reproductive parameters at different postpartum days in dairy Cows

The aim of this study was to evaluate the effect of Double-Ovsynch protocol on various fertility parameters at different postpartum days in dairy cows. Fifty-one Holstein cows were used and allocated into 4 groups. Group 1, group 2 and group 3 each contained 12 cows on the 25th, 32nd and 39th day of postpartum (as considered day 0), respectively. Group 4 (n=15) served as control group that nothing was applied until 40th day of postpartum then artificial insemination was performed at observed estrus. Cows in groups 1-3 were treated with GnRH on day 0, $PGF _{2\alpha}$ on day 7, GnRH on day 10, GnRH on day 17 and $PGF _{2\alpha}$ on day 24. The injection of GnRH was applied 56 h after the second $PGF _{2\alpha}$ injection and then timed artificial insemination (TAI) was performed at 16-20 h later (average 18th hour). The synchronisation rates changed between 66.67% and 91.67% in the study groups however a higher rate was observed in the groups 2 and 3. The lowest level of estrus symptoms at the TAI was seen in the groups 1-3 (P<0.05). The highest pregnancy rate after the first TAI (58.33%) was obtained in groups 2 and 3. The highest cumulative pregnancy rate (91.67%) were observed in groups 1 and 2. In conclusion, Double-Ovsynch protocol beginning at the different days of postpartum in dairy cow may provide a good reproductive performance without estrus detection.

Keywords:

synchronization, GnRH, cattle, cows, dairy cattle, dairy cows, female fertility, oestrus, postpartum period, pregnancy rate, prostaglandins, reproduction, reproductive efficiency, reproductive performance, reproductive traits,

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