Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa.
Department of Veterinary Anatomy, Faculty of Veterinary Science, University of West Kordofan, Gebaish, Sudan.
Microsc Res Tech. 2022 Mar;85(3):1160-1170. doi: 10.1002/jemt.23984. Epub 2021 Nov 13.
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.
在哺乳动物、鸟类和爬行动物的生殖阶段或繁殖季节，睾丸输出管系统经历了几个生理和形态变化。尽管日本鹌鹑（Coturnix japonica）被广泛用作禽类研究模型，但有关其输出管系统正常年龄相关组织形态变化的研究仍未见报道。本研究调查了日本鹌鹑在三个生殖阶段（即未成熟、青春期和成年期）睾丸输出管系统的组织学、超微结构和组织计量学变化。在未成熟和青春期鸟类中，睾丸网的上皮由简单的鳞状到低立方细胞组成，而在成年鸟类中，上皮为低立方到立方。在青春期和成年鸟类中，近端传出导管的非纤毛 I 型上皮细胞显示出一个亚顶的内吞作用装置，包括有被小窝、有被的顶小管和内体。与其他年龄组相比，成熟、有性活动的成年鸟类的输出管系统所有导管的上皮高度显著增加（p≤.001）。管腔和管状直径以及传出导管和附睾导管单位的横截面积随年龄显著增加（p≤.001）。结论是，随着鸟类成熟，日本鹌鹑睾丸输出管的形态和形态计量学发生变化。
