FOLLICULOGENESIS IN COLUMBA LIVIA (AVES: COLUMBIFORMES)

OLEA GABRIELA; SANDOVAL MA. TERESA; CAROU MA. CLARA; LOMBARDO DANIEL

BUENOS AIRES

Jornada; III Jornadas Internacionales de Instituto de Reproducción Animal (INITRA); 2012

During ovarian ontogeny of birds can recognize five key events: migration and colonization of primordial germ cells, oogonia differentiation and proliferation, germinal nests organization, the meiotic process beginning and folliculogenesis. The knowledge of these events is crucial for the interpretation of the processes involved in the differentiation of female gametes. This paper describes the changes and cellular events involved in the formation of the follicles of Columba livia. To do this, we examined the histology ovarian from stage embryos E42 and neonates, 2, 5, 7, 10 and 14 days post hatch. Samples were processed according to conventional techniques for paraffin embedding and staining with hematoxylin and eosin. The observations made it possible to identify four stages of folliculogenesis. In stage I the oogonia nests are grouped surrounded by a layer of pre follicular cells. Stage II is characterized by the initiation and meiotic arrest of prophase and primary oocytes. From stage III starts follicular cells surrounding each oocyte culminating in the organization of primordial follicles (stage IV).The results obtained show that in Columba livia, unlike the other species studied, folliculogenesis begins after hatching, and raising new questions about the mechanisms of control of folliculogenesis. Future studies will focus on the analysis of differentiation processes of follicular cells and endocrine control in the process.