Düvelerde Östrüs Siklusunun Folliküler ya da Luteal Evresinde Başlatılan Ovsynch Protokolünün Folliküler ve Luteal Senkronizasyon Üzerine Etkisi

Öz

In present study, the effect of ovsynch protocol started during follicular or luteal phase of estrous cycle on the follicular and luteal synchronization and pregnancy rate in heifers was investigated. Heifers received intramuscularly GnRH-agonist (10 μg buserelin acetate, first GnRH), PGF2α (150 µg dcloprostenol, PG) and second GnRH-agonist (second GnRH) on 0, 7 and 9 day, respectively, and they were inseminated at 18 h after the last injection (ST). On day 0, heifers were divided into two groups according to their plasma progesteron concentrations; Group I (n=13): progesterone concentration <1 ng/ml and Group II (n=15): progesterone concentration ≥1 ng/ml. The largest diameter of dominant follicle was measured on injection days. Blood was sampled on first GnRH, PG, ST and 7 days after insemination (ST7). Pregnancies were checked on d 35 after ST. Mean diameter (mm) of dominant follicle on d 0, 7 and 9 were detected 9.1±1.1, 9.3±0.7 and 11.4±0.9 in Group I and 10.5±0.6, 11.3±0.8 and 12.4±0.8 in Group II, respectively. Mean concentrations of progesterone on first GnRH, PG, ST and ST7 days were 0.5±0.1, 8.1±1.2, 0.9±0.2 and 4.0±0.6 in Group I and 3.2±0.7, 9.9±1.4, 0.5±0.1 and 3.7±0.7 in Group II, respectively. Estrous synchronization, ovulation and pregnancy rates were 77%, 69.2% and 30.8% in Group I, 93%, 80% and 26.7% in Group II, respectively. Except to progesterone concentration on the creation day of the groups (on the injection day of first GnRH), differences between two groups were not significant statistically (p>0.05). In , ovsynch started during follicular and luteal phase of cycle did not affect the follicular and luteal synchronization and pregnancy rate in heifers according to the results of this study.

Anahtar Kelimeler

• Ovsynch, Follicular phase, Luteal phase, Pregnancy rate, Heifers

Düvelerde Östrüs Siklusunun Folliküler ya da Luteal Evresinde Başlatılan Ovsynch Protokolünün Folliküler ve Luteal Senkronizasyon Üzerine Etkisi

Öz

Sunulan çalışmada düvelerde östrüs siklusunun folliküler veya luteal evresinde başlatılan ovsynch protokolünün folliküler ve luteal senkronizasyon ve gebelik oranı üzerine etkisi araştırıldı. Düvelerin östrüs siklusu 0, 7 ve 9. günlerde sırasıyla GnRH (10 μg buserelin asetat, birinci GnRH), PGF2α (150 µg d-kloprostenol, PG) ve GnRH (ikinci GnRH) uygulamalarıyla senkronize edildi. Düveler son enjeksiyondan 18 saat sonra tohumlandı (10. gün, ST). Düveler, 0. gün plazma progesteron konsantrasyonlarına göre iki gruba ayrıldı; progesteron konsantrasyonu <1 ng/ml olanlar (Grup I, n=13) ve progesteron konsantrasyonu ≥1 ng/ml olanlar (Grup II, n=15). Enjeksiyon günlerinde dominant follikülün en uzun çapı ölçüldü. PG, ST ve tohumlama sonrası 7. günlerde kan örnekleri alındı. Gebelikler ST sonrası 35. günde ultrason cihazı ile kontrol edildi. Dominant follikülün ortalama çapı (mm) birinci GnRH, PG ve ikinci GnRH günlerinde sırasıyla Grup I’de 9.1±1.1, 9.3±0.7 ve 11.4±0.9, Grup II’de 10.5±0.6, 11.3±0.8 ve 12.4±0.8 mm ölçüldü. Progesteron konsantrasyonu (ng/ml) birinci GnRH, PG, ST ve ST7 günlerinde sırasıyla Grup I’de 0.5±0.1, 8.1±1.2, 0.9±0.2 ve 4.0±0.6, Grup II’de ise 3.2±0.7, 9.9±1.4, 0.5±0.1 ve 3.7±0.7 tespit edildi. Östrüs senkronizasyonu, ovulasyon ve gebelik oranları sırasıyla Grup I’de %77, %69.2 ve %30.8, Grup II’de %93, %80 ve %26.7 oldu. Çalışmada grupların oluşturulmasında kriter olarak esas alınan 0. gündeki (birinci GnRH günü) progesteron konsantrasyonu dışında gruplar arasındaki bütün farklılıklar istatistiki olarak önemsiz oldu (P>0.05). olarak bu çalışmada elde edilen sonuçlara göre düvelerde östrüs siklusunun folliküler veya luteal evresinde başlatılan ovsynch yönteminin folliküler ve luteal senkronizasyon ve gebelik oranı üzerine farklı bir etkisi olmadı.

Anahtar Kelimeler

• Ovsynch, Folliküler evre, Luteal evre, Gebelik oranı, Düve

Kaynakça

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