Güvercinde (Columbidae columbiformes) Pekten Okulinin Histomorfolojik Yapısı

Abstract

Yapılan çalışmada güvercinde pekten okulinin histomorfolojik olarak araştırılması ve diğer kanatlı türleriyle farklılıklarının ortaya konulması amaçlandı. Çalışma materyalini Veteriner Fakültesi Hayvan Hastanesine getirilen ve kurtarılamayan iki adet güvercinlerden alınan sağlıklı göz dokusu örnekleri oluşturdu. Alınan doku örnekleri %10’luk nötral tamponlu formalin solüsyonunda 24 saat tespit edildi. Rutin doku takip işlemlerinden sonra bloklanan örneklerden seri kesitler alındı. Alınan bu kesitler Crossman’ın üçlü boyama yöntemiyle boyanarak araştırma mikroskobunda incelendi. Diğer kanatlı türlerinde olduğu gibi güvercinde de pekten okulinin nervus optikusun retinaya giriş bölgesinden vitreusa doğru uzandığı tespit edildi. Diğer kanatlılardan farklı olarak güvercinde pekten okulinin oturduğu kalın bazal laminada retinanın tamamıyla kopuntuya uğramadığı, optik sinir telleri katının bir süre daha devam ettiği görüldü. Pektenin oturduğu bazal kısımda büyük çaplı damarlara rastlandı. Bu damarların koroidden gelen damardan köken aldığı belirlendi. Bazalden apikale doğru gidildikçe damar çaplarının küçüldüğü tespit edildi. Bu nedenle damarlar çaplarına göre primer, sekonder ve tersiyer damarlar olarak sınıflandırıldı. Sınıflandırılan her damar grubundan rastgele örnekleme yöntemiyle 20 tanesinin çapları ölçülerek, ortalama damar çapı değerleri elde edildi. Pektenin bazal kısmında ayrıca az miktarda melanositlere de rastlandı. Bu melanositlerin de koroidin lamina vaskulozasında bulunan melanositlerden köken almış olabileceği düşünüldü. Pektenin apikale doğru uzanan kıvrımlarında damarlar ve melanositlerin yanı sıra pekteneal hyalositlere de rastlandı. Yapılan çalışmada elde edilen bulgular ile güvercin pekten okulisinde pekten damarlarının ve melanositlerin koroidden köken aldığı ilk olarak kanıtlanmış bulunmaktadır.

Keywords

• Damar,Güvercin,Histomorfoloji,Melanosit,Pekten okuli

Histomorphological Structure of Pecten Oculi in Pigeons (Columbidae columbiformes)

Abstract

It is aimed to research the histomorphological structure of pecten oculi in pigeons and to suggest the differences between other types of avian. Tissue samples from healthy eyes obtained from two pigeons came to the animal hospital were used. Tissue samples were fixed in 10% neutral-buffered formalin solution for 24 hours. After fixation samples were treated routine procedure and blocked. Serial sections were taken from the blocked. Those sections were examined under the microscope after stained with by Crossman’s triple stain. The pecten oculi projects from the optic nerve head into the vitreous chamber. Differently, it was seen that retina in pigeons was not completely separate from pecten base and ganglion cell layer were continued for a bit more. There were vessels with wide diameters on the basal part where pecten was located. This vessel was found to have originated from choroid. It was also seen that vessel diameters got smaller as it went to the apical from the basal. So, the vessels were classified as primer, secondary, and tertiary vessel. Diameters of 20 randomly chosen vessels from each sections were measured and an average diameter value was found. There was also a little amount of melanocyte in the basal part of the pecten. These melanocytes were based on the laminated vasculosa of the choroid. Pecten oculi were covered pecteneal membrane. Besides pecteneal hyalocytes were found in the pecteneal limiting membrane. According to the findings of the study, it was first proven to have originated from choroid that pigeon’s veins and melanocytes at the pecten oculi.

Keywords

• Vessel,Pigeon,Histomorphology,Melanocyte,Pecten oculi

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