STRUCTURAL ASPECTS OF THE LUNG IN JAPANESE QUAIL (COTURNIX COTURNIX JAPONICA )

Abstract

The histostructural study done at lung level is trying to distinguish a series of particular aspects of the primary and secondary bronchi; parabronchi; atrium and air capillaries; starting from the descriptions made by Adriansen; D. et al. (1994); Maina; J.N. et al. (2002; 2004); [1; 2; 3]. At the same time; the data that imply the presentation of the lymphoid population; known as Bronchus Associated Lymphoid Tissue – BALT; are considered [4]. The research material; represented by birds; males and females; belonging to the Coturnix coturnix japonica specie; aged between one and 70 days; was realized using techniques specific to optical and electronical microscopy; the resulted sections were photographiated and processed with a computer. At the beginning the mucosa of the primary bronchi is analyzed; in the structure of which mucosa tubulo-alveolar glands and lymphoid nodules of different sizes can be found; than; the wall of the secondary bronchi; structured only by mucosa and by the bronchial muscle; covered by a layer of connective tissue. The wall of the parabronchi contains mucosa; formed by a simple; cubic epithelium; along with lamina propria and a few layers of smooth muscular fibers. The atria are lined initially by a simple cubic epithelium; that gradually becomes squamous. The atria communicate with several infundibulae that are continued with air capillaries. The electronical microscopical images catch the aspect of the blood-gas barrier; and highlight the presence of two types of pneumocytes; that present mitochondria and vacuoles in the cytoplasm. The lungs usually lack in lymphoid nodule formations; although; beginning with the first day of life several lymphoid cells appear intralobular. No matter the age; the septa that separate the lobules are fine; sometimes barely perceptible. In very young birds the parabronchial lumen is very large and the structure of the lobular wall is simplified; for each atria compartment being corresponding a low number of infundibulae.