Ovary histomorphology of Odontophrynus americanus and Scinax fuscovarius

MANZANO CAROLINA; ZELARAYÁN LILIANA ISABEL; PUCCI ALCAIDE ANA

San Miguel de Tucumán

Jornada; Tercera Reunión Conjunta de Sociedades de Biología de la Republica Argentina; 2015

Asociación de Biología de Tucumán (ABT)

Anuran Amphibians are vertebrates that are characterized by different reproductive strategies, reflected in the morpho-physiological adaptations of the ovary, among others.In this work we analyze the ovary histomorphological aspects of sexually mature females in the reproductive period of two species of frogs, Scinax fuscovarius and Odontophrynus americanus.Ovaries of S. fuscovarius and O. americanus were processed and fixed in buffered formalin at pH 7 and included in Histowax. 5 µm cuts were stained with hematoxylin-eosin (HE), Mallory?s trichrome and Toluidine Blue (TB) at pH 7.In the ovaries of both species predominance of oocytes vitellogenic, fully grown oocytes and few previtellogenic was observed. Oogonia were not observed. In vitellogenic oocytes, migration of the germinal vesicle into the animal pole is distinguished, with progressive retraction of the nuclear envelope, numerous nucleoli and compact chromosomes at the nuclear periphery. The cytoplasm has large yolk platelets in the vegetative pole and smaller at the animal pole. On the periphery of the oocyte, forming the ovarian follicles, the follicular cells and theca cells are identified. Follicular covers include fibroblasts, collagen fibers, a conspicuous vascularization, follicular cells forming a squamous epithelium and vitelline envelope.The prominent number of vitellogenic follicles and fully grown follicles evidence that in both species the ovaries are in immediate ovulation period.