CİHAN KAÇAR, DUYGU KAYA, SAVAŞ YILDIZ, SEMRA KAYA, MUSHAP KURU, Şükrü Metin PANCARCI, Abuzer Kaffar ZONTURLU

The Effects on follicular dynamics caused by changing the Application Time of PGF 2 α and GnRh in the Cosynch protocol administered in Montofon cows with estrus stimulated by presynchronization

Bu çalışma ile presenkronizasyon oluşturulan Montofon ırkı ineklerde Cosynch protokolündeki ilk GnRH ile PGF 2 α uygulanma arası zamanının değiştirilmesinin folliküler dinamikleri üzerine etkisini araştırmak amaçlanmıştır. İlk olarak corpus luteum belirlenen tüm ineklere tek doz PGF 2 α enjekte edildi. Östrus tespitinden sonraki 6. gününde Cosynch protokolüne başlandı. Bu doğrultuda Grup 1de (GI; n=9) 0. gün GnRH, 7 gün sonra PGF 2 α enjekte edildi. Bu uygulamadan 56 saat sonra suni tohumlama yapıldı ve GnRH enjekte edildi. İkinci gruptaki ineklerde (GII; n=10) ise Cosynch protokolündeki PGF 2 α, ilk GnRH enjeksiyonundan 8 gün sonra uygulandı. Bu uygulamadan 56 saat sonra suni tohumlama yapıldı ve GnRH enjekte edildi. Follikül ve corpus luteum gelişimi ultrasonografi ile günlük takip edildi. Uygulamanın 6, 7 ve 8. günlerinde gruplar arasında follikül çaplarında istatistiksel olarak önemli bir fark belirlendi (P0.05). Sonuç olarak, seksüel siklusun 6. gününde Cosynch protokolü uygulanan ineklerde PGF 2 α uygulama zamanının bir gün uzatılmasının graaf follikülünün büyüklüğünü etkilemediği belirlendi.

Presenkronizasyon ile östrusu uyarılan Montofon ırkı ineklerde seksüel siklusun erken luteal döneminde uygulanan Cosynch protokolünde PGF 2 α ve GnRH uygulama zamanının değiştirilmesinin folliküler dinamik üzerine etkisi

The objective of this study was to investigate how follicular dynamics are afected by changing the initial injection times of PGF 2α and GnRH in the Cosynch protocol in Montofon cattle that have been administered presynchronization. Initially, all cattle whose corpus luteum was identified were administered an injection of PGF 2α. Six days after estrus was identified, the Cosynch protocol was started. In keeping with this, Group I (GI; n=9) was administered GnRH on day 0 and PGF 2 α 7 days later. Fifty-six h later, artificial insemination was performed and GnRH was injected. In the second group of cows (GII; n=10), PGF 2 α was administered in the Cosynch protocol 8 days after the first GnRH injection. Fifty-six h later, artificial insemination was performed and GnRH was injected. Development of the follicle and the corpus luteum was monitored each day with ultrasonography. On days 6, 7 and 8 of the procedure, a statistically significant diference in the follicle diameters was identified between the groups (P<0.05). No significant diference between the groups was identified in the dominant follicle diameter during artificial insemination (P>0.05). In conclusion, we determined that for cattle administered the Cosynch protocol on the 6th day of the sexual cycle, extending the application time of PGF2 α by one day in did not afect the size of the Graafian follicle.

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