Mehmet Osman ATLI, Mehmet Salih KAYA, Mehmet KÖSE

Effect of exogenous progesterone and gonadotropin-releasing hormone application on maintenance of pregnancy in early pregnant ewes after prostaglandin F2 alpha injection

Amaç: Sunulan bu deneysel çalışmada, koyunlarda gebeliğin erken döneminde prostaglandin F2alfa (PGF2?) enjeksiyonu sonrası eksojen progesteron (P4) ve gonadotropin releasing hormon (GnRH) uygulamalarıyla plazma P4 düzeyinin yüksekliğinin sürdürülerek gebeliğin devamlılığının sağlanabileceği test edildi. Gereç ve Yöntem: Bu amaçla, 9 gebe koyun 18. günde (çiftleşme günü 0. gün olarak kabul edildi) iki gruba ayrıldı; (1) PGF2? grubu (18. gün 125 mcg d-cloprostenol enjeksiyonu, n=5); (2) PGF2? + P4 + GnRH grup (18. gün 125 mcg d-cloprostenol enjeksiyonu + 20 mg flugestone acetate sponge (P4 sponge), intravaginal 7 gün süreyle, 22. gün 10 mg buserelin acetate (GnRH analoğu) enjeksiyonu, n=4). P4 sponge 25. günde uzaklaştırıldı. Çiftleştirme sonrası 18 ve 19. günlerdeki plazma P4 konsantrasyonu ECLIA ile ölçüldü. Gebelik muayeneleri 18, 22, 25 ve 35. günlerde rektal yolla ultrasonografi ile yapıldı. Gruplar arasındaki istatistiki farklılıklar ki-kare ile analiz edildi.Bulgular: P4 konsantrasyonu iki grupta da 19. günde 1 ng/mL'nin altına düştü. PGF2? grubundaki koyunların tamamında (5/5) gebelik 25. güne kadar sonlanırken, PGF2? + P4 + GnRH grubundaki koyunlarda (4/4) ise P4 sünger uygulaması gebeliğin sonlanmasını önledi (P

Gebeliğin erken dönemindeki koyunlarda prostaglandin F2 alfa enjeksiyonu sonrası eksojen progesteron ve gonadotropin salınım uyarıcı hormon uygulamasının gebeliğin devamlılığı üzerine etkisi.

Aim: We tested the hypothesis that exogenous progesterone (P4) and gonadotropin-releasing hormone applications (GnRH) would prevent detrimental effect of prostaglandinF2alfa (PGF2?) on early pregnancy in ewes by sustaining high plasma progesterone level.Materials and Methods: For this purpose, nine pregnant ewes (mating=0) were divided into 2 groups on day 18 as follows: (1) PGF2? group (125 mcg of d-cloprostenol injection on day 18, n=5); (2) PGF2? + P4 + GnRH group (125 mcg of d-cloprostenol injection on day 18 + 20 mg flugestone acetate (P4) for 7 days + 10 mg of buserelin acetate injection, on day 22, n=4). P4 was withdrawn on day 25. P4 concentration was measured on days 18 and 19 by ECLIA. Pregnancies were examined by using transrectal ultrasonography on days 18, 22, 25, and 35. Statistical difference between groups was analysed by chi-squared test.Results: P4 concentration declined to below 1 ng/mL on day 19 in both groups. While all pregnancies were terminated in PGF2? group by day 25, P4 prevented pregnancy loss in PGF2? + P4 + GnRH group (P

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