Mehmet KÖSE, Ahmet Hamdi AKTAŞ, Bülent BÜLBÜL, Mesut KIRBAŞ

Konya Merinosu toklularda aşımla birlikte gonadotropin-releasing hormon veya human chorionic gonadotropin uygulamasının kuzulama performansına etkisi

Amaç: Bu çalışma da Konya Merinosu toklularda aşımla birlikte gonadotropin-releasing hormon (GnRH) veya human chorionic gonadotropin (hCG) uygulamasının senkronizasyon periyodu ve izleyen siklusta yaptırılan aşımlar sonrası kuzulama performansına etkisinin belirlenmesi amaçlandı. Gereç ve Yöntem: Materyal olarak 16-20 aylık 36 baş Konya Merinosu toklu kullanıldı. Tokluların östrüsleri 0. gün 4 μg GnRH ve 5. gün 150 μg prostaglandinF2α (PGF2α) uygulanmasıyla senkronize edildi. PGF2α enjeksiyonu sonrası östrüste olduğu tespit edilen toklular fertil oldukları daha önceden bilinen koçlarla bir kez çiftleştirildi. Aşım sonrası toklular sürüden uzaklaştırıldı ve üç gruba ayrıldı. Birinci gruptaki toklulara (n=14) 200 IU hCG, ikinci gruptakilere (n=12) 4 μg GnRH ve üçüncü gruptakilere (kontrol, n=10) 1 mL serum fizyolojik kas içi enjekte edildi. Gebelik muayeneleri aşım sonrası 30. günde ultrasononografi cihazı kullanılarak transrektal yoldan yapıldı. Bulgular: Sunulan çalışmada gebe kalan, doğum yapan, ikiz doğum yapan koyun oranı ve kuzu verimi sırasıyla hCG grubunda %85.71, %85.71, %33.3 ve 1.14, GnRH grubunda %75.0, %66.67, %12.5 ve 0.75, kontrol grubunda ise %100, %80, %37.5 ve 1.10 olarak belirlendi. Gruplar arasında kuzulama performansı ve incelenen reprodüktif parametreler arasındaki farklar istatistiki açıdan önemli bulunmadı (p>0.05). Öneri: Sonuç olarak östrüsleri senkronize edilen toklularda aşımla birlikte GnRH veya hCG uygulamalarının kuzulama performansı üzerine etkisinin olmadığı kanaatine varıldı.

The effect of gonadotropin- releasing hormone or human chorionic gonadotropin administration at mating on lambing performance in Konya Merino yearling ewes.

Aim: In this study, it was aimed to determine the effects of the exogenous gonadotropin-releasing hormone (GnRH) or human chorionic gonadotropin (hCG) application at mating on lambing performance in synchronization and following cycle in Konya Merino yearling ewes. Materials and Methods: Thirty six yearling Merino ewes, aging 16-20 months, were used as material. Estrus of ewes was synchronized with 4 μg GnRH on d 0 and 150 μg prostaglandinF2α (PGF2α) on day 5, intramuscularly. After PGF2α injection, the ewes detected to be in estrus were mated with a ram, whose fertility was known previously, and they were divided into three groups. Group I (n=14) were injected 200 IU hCG, Group II (n=12) were injected 4 μg GnRH, and Group III (control group, n=10) were injected 1 mL placebo at mating. Pregnancy was diagnosed on day 30 by using transrectal ultrasonography. Results: In the present study, pregnancy, birth, twinning rate and lambing performance were 85.71%, 85.71%, 33.3% and 1.14 in hCG group, 75.0%, 66.67%, 12.5%, and 0.75 in GnRH group, and 100%, 80%, 37.5% and 1.10 in control group, respectively. There was no significant difference among groups for lambing performance and studied reproductive parameters (p>0.05). Conclusion: In conclusion, the injection of GnRH or hCG in Merino ewes at mating was not effective on lambing performance.

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