Oogenesis is accompanied by cyclic morphological changes in hepatocytes of Neotropical freshwater fish Piabina argentea

Abstract

We determined for the first time the reproductive biology of Piabina argentea through macroscopic and microscopic analysis of ovaries and evaluated the morphological changes in hepatocytes. Two hundred and 46 specimens were collected, 204 females and 42 males, between March 2014 and February 2015. Biometrics data were obtained. From females, gonad and liver samples were conducted to histological, histochemical and immunohistochemical techniques. Mature ovaries were used to determine absolute and relative fecundity. Total length and body weight values indicated that females were larger than males. The estimated weight-length ratio showed negative allometric growth. The absolute fecundity average was 171.83 ± 59.89 oocytes per ovary. In addition, females spawning capable and regressing stages were found throughout the sampling period and the presence of all oocyte types in regressing stage ovaries indicated asynchronous oocyte development and multiple spawning. From regenerating to spawning capable stage the oocytes accumulated yolk in cytoplasm became bigger. While in the liver hepatocytes with a larger cell area during regenerating stage and proliferative activity in the spawning capable stage were observed. Thus, our results indicate that P. argentea had an opportunistic reproductive strategy and cyclic morphological changes of hepatocytes occurred during the oogenesis.

Histoquímica De Oócitos De Peixes Do Gênero Steindachnerina (Characiformes: Curimatidae)

“…A literatura apresenta estudos citogenéticos (21), análises moleculares e genéticas (22,23), estudos histoquímicos de células branquiais (24) referentes ao gênero Steindachnerina, mas pouco se fala a respeito da biologia reprodutiva desse grupo (25), ou até mesmo da descrição histológica das células reprodutivas desses peixes, (26,27) caracterizando-os ou mesmo comparando suas atividades funcionais a outros órgãos ou sistemas como, por exemplo, a forte relação entre a atividade hepática e a oogênese. Em alguns gêneros foi observado uma relação direta entre ambos os processos (28,29…”