emale sex inversion as a reason for an unbalanced sex ratio in the neotropical species Brycon orbignyanu

Autor(es)

Quirino, Patricia Postingel ^{[1, 2]} ; Ribeiro Delgado, Maria Luiza ^{[1, 2]} ; Gomes-Silva, Luciane ^{[1, 2]} ; Benevente, Cristiane Fernanda ^{[1, 2]} ; Grigoli-Olivio, Maiara Luzia ^{[1, 3]} ; Bianchini, Barbara Correa ^[1] ; Ninhaus-Silveira, Alexandre ^{[1, 2, 3]} ; Verissimo-Silveira, Rosicleire ^{[1, 2, 3]}

Afiliação do(s) autor(es)

^[1] UNESP Univ Estadual Paulista Julio de Mesquita Fi, Dept Biol & Zootecnia, LINEO Lab Neotrop Ichthyol, Campus Ilha Solteira, Rua Moncao 226, BR-15385000 Ilha Solteira, SP - Brazil

^[2] IBB UNESP Inst Biociencias Botucatu, Programa Posgrad Ciancias Biol Zool, Botucatu, SP - Brazil

^[3] FEIS UNESP Univ Estadual Paulista Julio de Mesqui, Programa Posgrad Ciencia & Tecnol Anim, Fac Engn Ilha Solteira, Ilha Solteira - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AQUACULTURE RESEARCH; v. 53, n. 5 DEC 2021.
• Citações Web of Science: 0

Resumo

The objective of this study was to temporally identify sex differentiation to morphologically characterize the formation of female and male germinal epithelium and verify the occurrence of the sex disproportion reported for this species in aquaculture. Specimens of Brycon orbignyanus cultivated in water recirculation systems with a constant temperature of 27 +/- 0.5 degrees C were used. Monthly samplings of B. orbignyanus (n = 15) were performed from two months of age until 1 year of age, and posteriorly isolated sampling was performed on specimens of two and three years of age. The gonads of the specimens were removed and processed for light microscopy. In the beginning, the undifferentiated gonads develop into ovaries (females; at three months of age) and functional testicles (primary males; at five months of age); however, some of the females go through a sex inversion process creating intersex individuals and posteriorly secondary males (at five months of age). Due to the processes of sex inversion and gonadal remodelling, the population sex proportion fluctuates until it is finally established at 1 female:2 male. Females above 15 cm are differentiated, while in males (primary and secondary), differentiation will only occur after the animal reaches 20 cm. At the end of the first year of age, primary males and secondary males reach sexual maturity, while female sexual maturity is only observed at three years of age. (AU)

• Processo FAPESP: 13/24527-8 - Avaliação histológica e estereológica da espermatogênese do Astyanax altiparanae (Characiformes, Characidae)
• Beneficiário: Maira da Silva Rodrigues
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 14/23379-8 - Transplante xenogênico de espermatogônias tronco em Characidae (Teleostei, Characiformes)
• Beneficiário: Rosicleire Veríssimo Silveira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 19/27406-3 - Caráter sexual secundário em Brycon orbignyanus (Characiformes: Bryconidae) e sua associação com o desenvolvimento testicular
• Beneficiário: Bárbara Correa Bianchini
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica