Ontogeny of the testicular excurrent duct system of male Japanese quail (Coturnix japonica): A histological, ultrastructural, and histometric study

Abstract

The testicular excurrent duct system undergoes several physiological and morphological changes during the reproductive stage or breeding season in mammals, birds, and reptiles. Studies on normal age-related histomorphological changes in the excurrent duct system of Japanese quails (Coturnix japonica) remain unreported, despite the extensive use of this bird as an avian model in research studies. The current study investigated the histological, ultrastructural, and histometric changes in the testicular excurrent duct system of the Japanese quail during three reproductive stages, namely prepubertal, pubertal, and adult. Simple squamous to low cuboidal cells formed the epithelia of the rete testis in prepubertal and pubertal birds, while in adult birds the lining was low cuboidal to cuboidal. In pubertal and adult birds, the nonciliated Type I epithelial cells of the proximal efferent duct displayed a subapical endocytotic apparatus comprising coated pits, coated apical tubules, and endosomes. There was a significant increase (p ≤ .001) in epithelial heights of all ducts of the excurrent duct system in the mature, sexually active, adult birds when compared to the other age groups. The luminal and tubular diameters, and the cross-sectional areas of efferent ducts and the epididymal duct unit increased significantly (p ≤ .001) with age. It is concluded that the morphology and morphometry of the excurrent ducts of the testis of the Japanese quail change as birds mature.

Morpho-Histology and Morphometry of Chicken Testes and Seminiferous Tubules among Yellow-Feathered Broilers of Different Ages

“…Razi et al described the histology, anatomy, and morphometry of the male genital system in mature Iranian Native White Roosters (IWR) [10]. Testis morphology, histology, and morphometry have also been described in other avian species including Japanese quail [11,12], Duck [13,14], turkey [15], ostrich [8], and dove [16]. Spermatogenesis has been thoroughly investigated in mammals, and most of our understanding of the developmental and transformative mechanisms in the spermatid originates from these studies (spermatogenesis in mammals [17], birds [18,19], also in nonmammalian vertebrates [20]).…”

Cemani chicken: characteristics of fresh semen, testes morphometric, and the relationship between the two traits

“…Morphometrics is necessary to evaluate quantitative alterations in testicular size and spermatogenic function [2; 3]. Various studies have been conducted on roosters about testicular enhancement, weight, morphometrics, and histology [4]. Testicular morphology, histology, and morphometry have also been characterized in different avian species, such as Japanese quail [4], ducks [5], and pigeons [6].…”

“…Various studies have been conducted on roosters about testicular enhancement, weight, morphometrics, and histology [4]. Testicular morphology, histology, and morphometry have also been characterized in different avian species, such as Japanese quail [4], ducks [5], and pigeons [6]. Testicular weight, length, width, and testicular circumference are measurable morphological traits.…”