Histological and anatomical study of the White Rooster: testis, epididymis and ductus deferens

This study was carried out to investigate the histological and anatomical description of the male genital tract in Iranian Native White Roosters (IWR). The seminiferous tubules had a dense and compact organization. An average of 12 layers of cells was seen in the seminiferous tubules epithelium. The spermatogonal cell layer showed some variation between different birds in 1-3 layers; however, the spermatocyte, secondary spermatocytes and spermatids were arranged in 2, 3-4 and 3-5 layers, respectively. The testicles were oval in shape, placed on the left and right sides of midline, situated on the caudal aspect of the lungs and the ventral aspect of either the right or left kidneys, and the visceral surfaces of the left and right lobes of the liver. The epididymis was not divided into recognizable parts and was frontally attached to the corresponding testis on its dorsomedial aspect continuous with the ductus deferens. The ductuli efferentis were moderately large with pseudostratified columnar epithelium lined with three cell types, including ciliated, non-ciliated and basal cells. The connective ducts were covered with scare ciliated pseudostratified columnar epithelium. The epithelium of the epididymis was pseudostratified and columnar, embedded in a loose connective tissue. The proximal part of the ductus deferens was covered with pseudostratified columnar epithelium, which was continuous with simple cuboidal epithelium towards the distal portion. Anatomical studies revealed a large sac-like accessory process that consisted of two non-discrete parts in the frontoventricular region of the testes between the epididymis and the ductus deferens, which was closely related ventrally to the epididymis and laterally to the kidneys. This organ was lined with stratified cuboidal epithelium with thick clear mucosal muscle. The tunica sub mucosa was evident, and the outer layer was composed of a fibrous capsule with a well-developed vascular supply. This suggested that the role of the sac-like accessory process was as an organ to supply sperm, equivalent to the tail of the epididymis in mammals.