Anatomical, histological and immunohistochemical study of testicular development in Columba livia (Aves: Columbiformes)

OLEA, GB.; AGUIRRE, MV.; LOMBARDO, DM.

ACTA HISTOCHEMICA

ELSEVIER GMBH, URBAN & FISCHER VERLAG

Año: 2018 vol. 120 p. 446 - 455

0065-1281

In this work, testicular ontogeny is analyzed at the anatomical, histological and immunohistochemical levels; the latter through the detection of GnRHR and PCNA in the testicles of embryos, neonates, and juveniles of Columba livia. This research is intended to provide data that can be used to perform comparative studies with other bird species. We analyzed 150 embryos, 25 neonates, and 5 juveniles by means of observations under a stereoscopic magnifying glass and scanning electron microscope (SEM). The histological analysis was performed using hematoxylin-eosin staining techniques and the PAS reaction. For the immunohistochemical analysis, the expression of GnRHR and PCNA in embryos corresponding to stages 41, 43 and in neonates of 2, 5, 7 and 75 days post-hatch was revealed in testicular histological preparations. From the results obtained it was possible to observe that gonadal outline are evident in stage 18. In stage 29, the testes are constituted of a medulla in which the CGPs are surrounded by the Sertoli cells, constituting the seminiferous tubules. From stage 37 a greater organization of the tubules is visualized and at the time of hatching the testicle is constituted of the closed seminiferous tubules, formed of the CGPs and Sertoli Cells.The Leydig cells are evident outside the tubules. In the juvenile stages, the differentiation of germline cells and the organization of small vessels that irrigate the developing testicle begin to be visible. In the analyzed stages, the immunodetection of the GnRHR receptor and PCNA revealed specific marking in the plasma membrane and the perinuclear zone for GnRHR and the nucleus of the germline cells in juvenile testicles for PCNA. These results can be used as a basis for further study of endocrine regulation events during testicular ontogeny in avian species.