Light and Scanning Electron Microscopic Features of the Pecten Oculi in the Aseel Chickens (Gallus domesticus)

Abstract

The most striking and interesting feature of the eye in birds is the pecten oculi. In this study, the anatomical and histological features of pecten oculi in the eyes of Aseel chickens were determined by the light and electron microscopic applications. For the study were used four adult Aseel chickens. After the enucleation procedure, eyes were fixed in 10% buffered formalin solution. Eyes whose morphological structures were examined under a stereomicroscope were then prepared for electron microscopy and histological examinations. In the examination, it was determined that the pecten oculi was located on the retina layer in the posterior half of the eye. It was determined that the right and left pecten oculi consisted of an average of 20-22 pili. The mean basal length of pectenes was 7.92 mm, apical length was 4.45 mm, and height was 3 mm. When the cross-sectional surface of the pectineal folds was examined, large diameter and oval-shaped vessels located in the center of the folds and many capillary blood vessels coursing around these vessels were detected. Numerous and diffuse melanocytes were detected on both the peripheral and central regions of pili sections. As a result, it was determined that pecten oculi in Aseel chickens was generally compatible with the characteristics reported in other diurnal bird species in terms of morphological and histological features.

Keywords

• Pecten oculi
• eye
• Aseel chicken
• morphology
• histology
• SEM

Aseel Tavuklarda (Gallus domesticus) Pecten Oculi’nin Işık ve Elektron Mikroskopik Özellikleri

Abstract

Kuşlarda gözün en göze çarpan ve ilginç özelliği pecten oculi’dir. Bu çalışmada Aseel tavukların gözünde bulunan pecten oculi’nin anatomik ve histolojik özellikleri ışık ve elektron mikroskopik uygulamalar yardımıyla tespit edildi. Çalışma için dört adet yetişkin Aseel ırkı tavuk kullanıldı. Enükleasyon işlemi sonrası gözler %10’luk tamponlu formalin solüsyonunda tespit edildi. Morfolojik yapıları stereomikroskop altında incelenen gözler daha sonra elektron mikroskop ve histolojik incelemeler için hazırlandı. Yapılan incelemede pecten oculi’nin gözün arka yarımında, retina tabakası üzerinde bulunduğu belirlendi. Sağ ve sol pecten oculi’lerin ortalama 20-22 adet piliden (kıvrımdan) oluştuğu tespit edildi. Pectenlerin ortalama bazal uzunluğu 7,92 mm, apikal uzunluğu 4,45 mm, yüksekliği ise 3 mm olarak belirlendi. Pektineal kıvrımların kesit yüzeyi incelendiğinde kıvrımların merkezine yerleşmiş büyük çaplı ve oval şekilli damarlar ile bu damarların çevresinde seyreden çok sayıda kılcal kan damarları tespit edildi. Pili kesitlerinin hem perifer hem de merkez bölgeleri üzerinde yaygın ve çok sayıda melanosit varlığı tespit edildi. Sonuç olarak, Aseel ırkı tavuklarda pekten oculi’nin morfolojik ve histolojik yapısının diğer gündüz aktif kuş türlerinde bildirilen özelliklerle genel olarak uyumlu olduğu belirlenmiştir.

Keywords

• Pecten oculi
• göz
• Aseel tavuk
• morfoloji
• histoloji
• SEM

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