Laktasyonda Olan ve Laktasyonda Olmayan Kısraklarda Altrenogest Uygulaması Sonrası Serum Östrojen, Progesteron, AMH ve IGF-1 Düzeylerinin Araştırılması

Öz

Sunulan çalışmanın amacı, altrenogest ile senkronize edilen laktasyondaki kısraklarda aşım zamanına kadar geçen süreçte ovaryumlardaki folliküler gelişimlerin ultrasonografi ile takibi, serum östrojen, progesteron, AMH ve IGF-1 konsantrasyonlarının ölçülmesi ve gebelik oranlarının değerlendirilerek bu verilerin laktasyonda olmayan kısraklarla karşılaştırılmasıdır. Çalışma, üreme sezonun başladığı ve ovaryumların aktif olduğu üreme sezonunda gerçekleştirildi; laktasyonda olan kısraklar Grup 1’e (n=8) ve laktasyonda olmayan kısraklar Grup 2’ye (n=8) dahil edildi Her iki gruba altrenogest (Regumate®) ve prostaglandin F2α ile senkronizasyon gerçekleştirildi. Laktasyonda olmayan kısrakların dominant follikül çapları laktasyonda olanlara göre daha büyük bulundu. Çalışma süresince toplanan kan örneklerinde östrojen, progesteron, AMH ve IGF-1 düzeyleri laktasyondaki kısraklarda belirgin olarak düşük bulundu. Laktasyonda olmayan kısrakların ilk aşımda gebe kalma oranı (%75), laktasyonda olan kısraklarla (%62.5) benzer bulundu (x2=1.54, P=0.62). Altronogest ile senkronize edilen kısraklarda laktasyonun ve tayın varlığının ovaryum faaliyetlerine, ovaryum steroid düzeylerine, AMH ve IGF-1 düzeylerine önemli oranda etki ettiği kanısına varıldı. Bu nedenle laktasyonda olan kısraklarda gebelik oranlarını arttırmak amacıyla altrenogest ile seksüel siklus senkronizasyonunun uygun bir yöntem olduğu düşünüldü.

Anahtar Kelimeler

• Altrenogest
• anti-müllerian
• kısrak
• laktasyon
• östrojen
• progesteron

The Investigation of Serum Estrogen, Progesterone, AMH and IGF-1 Profiles in Lactating and Non Lactating Mares after Altrenogest Administrations

Öz

The objective of this study is to follow up the follicular growth in ovaries until mating by ultrasonography to determine of pregnancy rates, serum estrogen, progesterone, AMH and IGF-1 concentrations in mares which synchronized with altrenogest and to compare the obtained data with non-lactating mares. The study was carried out during breeding season while ovaries were active; lactating mares were included in Group 1 (n = 8) and non-lactating mares in Group 2 (n = 8). In both groups, synchronization was performed by administration of altrenogest (Regumate®) and prostaglandin F 2 alpha (PGF2α). Dominant follicle diameters of non-lactating mares were found to be greater than those of lactating ones. During the study, estrogen, progesterone, AMH and IGF-1 levels were significantly lower in the lactating mares. The non- lactating mares were found to have a first pregnancy conception rate (75%), similar to that of lactating mares (62%) (x2=1.54, P=0.62). It was concluded that in the mares synchronized with altrenogest, the presence of lactation and the foal are significantly influences ovarian activities, ovarian steroid levels, AMH and IGF-1 levels. Therefore, in order to increase pregnancy rates in lactating mare, sexual cycle synchronization with altrenogest are considered to be a suitable method.

Anahtar Kelimeler

• Altrenogest
• anti müllerian
• estrogen
• lactation
• mare
• progesterone

Kaynakça

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