Modifiye U-synch Protokolü ile Mevsim Dışı Senkronize Edilen Akkaraman Kangal Irkı Prepubertal Kuzu ve Primipar Koyunlara GnRH ve hCG Uygulamalarının Fertilite Üzerine Etkisi

Yıl 2019, Cilt: 1 Sayı: 2, 60 - 68, 15.08.2019

Abdurrahman Takcı

Öz

Koyunlar mevsimsel poliöstrik hayvanlardır. Yerli gen kaynağımız olan Akkaraman-Kangal ırkı koyunlar da yıl içinde sadece üreme sezonunda (sonbahar aylarında) seksüel aktivite göstermektedir. Bundan dolayı üreme sezonu dışında (anöstrüste) gebelik elde etmek için farklı seksüel uyarımlar yapılması gerekmektedir. Bu amaçla mevcut çalışma her grubun 15 baş prepubertal kuzu (10-14 aylık) ve 10 baş primipar koyun (postpartum 55-70.günlerinde olan) ihtiva ettiği üç grup ile derin anöstrüs döneminde (Mayıs-Haziran) olan hayvanlarda yürütülmüştür. Bütün gruplara 0. gün 100 μg gonadorelin diasetat tetrahidrat kas içi enjeksiyonu ile birlikte 20 mg flurogestan asetat içeren sponj 7 gün süreyle vaginada tutulmuş ve sponj çıkarıldığı gün 131,5 μg kloprostenol sodyum ve 600 IU eCG kas içi enjeksiyonları yapılmıştır. Sponj çıkarıldıktan 56 saat sonra (10. gün); Grup 1’deki hayvanlara 100 μg gonadorelin diasetat tetrahidrat (GnRH), Grup 2’deki 600 IU hCG enjeksiyonu yapılırken, Grup 3 (Kontrol)’deki hayvanlara 2 ml serum fizyolojik enjeksiyonlarını takiben koç katımı yapıldı ve koçlar 5 gün boyunca (10-15. gün)  koyunlarla birlikte kaldı. Gruplar arasında östrus gösterme, gebe kalma oranları ve eşit günlerde progesteron seviyeleri değerlendirilmiş olup gruplar arasında bu parametreler yönünden oluşan fark istatistiki yönden anlamlı bulunmadı. Modifiye U-synch yöntemlerinin prepubertal toklu ve primipar koyunlarda reproduktif etkinliği benzer bulundu. Sonuç olarak Akkaraman Kangal ırkı prepubertal toklu ve primipar koyunlarda modifiye U-synch yöntemleri ile anöstrüste gebelik elde edilebileceği belirlenmiştir. 

Anahtar Kelimeler

Akkaraman, anöstrus, kangal, prepubertal, prepubertal, koyun

The Effects of GnRH and hCG Applications on Fertility in Akkaraman Kangal Prepubertal Lambs and Primiparous Sheep with Synchronized Modified U-synch Protocol and out of Breeding Season

Öz

Sheep are seasonally polyestrous. Our native genetic source Akkaraman-Kangal breed sheep show sexual activity only in breeding season (months of fall) throught year too. Diffirent induction methods are needed to produce lamb out of breeding season). For this purpose, the study conducted on 3 groups which involve 15 prepubertal ewe lamb (10-14 months of age) and 10 primiparous ewe (55-70 days of postpartum) in deep anestrous (may-june). Each group was recieved 100 µg gonadorelin diacetate tetrahydrate (GnRH) together with progestrone including sponge (20 mg flugeston acetate). Sponge was out 7 days (7th Day) later following 131,5 µg PGF2α and 600 IU eCG injection.  100 µg gonadorelin diacetate tetrahydrate (GnRH), 600 IU hCG and 2 ml sterile saline solution was injected to group 1, 2 and 3 respectively at the 56th hour following sponge out. Ram were introduced to the groups for 5 days after injection (between 10-15th days). Progestrone levels, Estrous and pregnancy rate were evaluted. Significant diffirences was not observed between groups. Reproductive efficiency of the modified U-synch method found to be smilar in prepubertal ewe lambs and primiparous ewes.  In conclusion, it was determined that a reasonable pregnancy rate can be achieved with modified U-synch method in Akkaraman-Kangal prepubertal ewe lambs and primiparous ewes.

Anahtar Kelimeler

Akkaraman, anestrus, kangal, prepubertal, sheep

Kaynakça

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