MİTHAT EVECEN, ÜMÜT CİRİT, KAMBER DEMİR, Elif KARAMAN, GÜL BAKIRER ÖZTÜRK, Asiye İzem HAMZAOĞLU, SEMA BİRLER, SERHAT PABUCCUOĞLU

Effect of oocyte diameter on in vitro embryo production in dogs

Köpeklerde, in vitro embriyo üretimi amacıyla henüz başarılı bir yöntem bulunmamaktadır. Günümüze kadar yapılan in vitro çalışmalarda, sadece bir adet blastosist elde edildiği bildirilmiştir. Sunulan çalışmada, köpeklerde farklı oosit çaplarının (≤100 μm ve >100 μm) in vitro maturasyon (İVM), in vitro fertilizasyon (İVF) ve in vitro kültür (İVK) sonrası embriyonik gelişim üzerine etkisinin araştırılmasını amaçlandı. Çalışma iki aşamada gerçekleşti. İlk aşamada (Deney I), farklı oosit çaplarının İVM üzerine etkisi araştırıldı. Bu aşamanın sonunda oositlerin olgunlaşma durumları, aseto-orsein boyama metoduyla belirlendi. Çalışmanın ikinci aşamasında ise (Deney II), İVM sonrasında oositler taze sperma ile 24 saat İVF’a tabii tutuldular ve ardından yedi gün boyunca in vitro kültüre edildiler. Embriyoların gelişimsel kontrolleri her 24 saatte bir mikroskop bakısıyla kontrol edildikten sonra, yedinci günün sonunda aynı metotla fikze edilip boyanarak değerlendirildiler. İVM-İVF sonuçları karşılaştırmasında, büyük çapa sahip olan oositlerin, küçük olanlara göre daha yüksek oranda olgunlaşabildiği ve daha fazla oranda bölünmeler gösterebildiği saptandı (P

Anahtar Kelimeler:

morula, in vitro döllenme, in vitro kültür, embriyo, embriyonik gelişim, embriyo kültürü, köpek, yarılma, blastosist, dişi köpek, oogenez, oosit, oosit olgunlaşması

Köpeklerde oosit çapının in vitro embriyo üretimi üzerine etkisi

In vitro embryo production has not been confidently applied to the dog successfully. Up to date, only one blactocyst have been achieved by in vitro culture. Therefore, the aim of the present study was to examine the effects of different oocyte diameters (≤100 μm and >100 μm) on in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) of immature dog oocytes. The study was performed in two steps. At the first step (experiment I), effects of two different oocyte diameters on IVM of dog oocytes were investigated. The nuclear maturation rates were evaluated by aceto-orcein staining method at the end of the IVM. At the second step (experiment II), in vitro matured oocytes were fertilized with fresh spermatozoa for 24 h and in vitro cultured for 7 d. At the end of the IVC period, embryonic development was assessed by microscopic observation at 24 h intervals and fixed for staining by aceto-orcein staining method after 7 days. In comparison relating in IVM and IVF rates, larger oocytes have higher maturation (P<0.05) and cleavage (P<0.01) rates than the smaller ones. Unfortunately, none of the oocyte was reached to morula or blactocyst stage in both groups. In conclusion, it is demonstrated that the oocyte diameter may be a helpful selection criteria for dog in vitro embryo production.

Keywords:

morula, in vitro fertilization, in vitro culture, embryos, embryonic development, embryo culture, dogs, cleavage, blastocyst, bitches, oogenesis, oocytes, oocyte maturation,

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