A case of intersex occurrence in Steindachneridion parahybae (Steindachner, 1877) (Siluriformes: Pimelodidae) under captivity condition: a cytogenetic and morphological study

Autor(es)

Honji, Renato M. ; Caneppele, Danilo ; Pandolfi, Matias ; Lo Nostro, Fabiana L. ; Moreira, Renata G.

• Tipo de documento: Artigo Científico
• Fonte: Neotropical Ichthyology; v. 14, n. 4 2016.
• Citações Web of Science: 3

Resumo

ABSTRACT Little is known about reproductive biology of endangered Steindachneridion parahybae , a gonochoristic teleost species inhabiting the Paraíba do Sul River Basin, and herein is the first description of intersex in S. parahybae juvenile. The normal appearance of ovaries and testes in juvenile from the same lot of breeding were also described for comparison, even as cytogenetic analysis was performed in these juveniles. One specimen was a priori classified as female due to the macroscopic characteristic of ovaries, with small yellow oocytes, without fringes (a main characteristic of catfish male), and larger than testes; however the microscopic analysis revealed the presence of ovotestes, including the complete spermatogenesis. S. parahybae had diploid number, 2n = 56 chromosomes with no evidence of differentiated sex chromosomes or supernumerary chromosomes among them. These findings may be due to the result of exposure to endocrine disrupting compounds or may also be influenced by environmental conditions. The possibility of intersexes might also happen spontaneously and it cannot be ruled out. Therefore, the functional significance and reproductive consequences of this anomaly remain to be determined, suggesting that this species may be susceptible to endocrine disruption. These results contribute to gain expertise about reproductive biology of an endangered species in captivity. (AU)

• Processo FAPESP: 11/50288-5 - Influências ambientais sobre os mecanismos de determinação e diferenciação sexual em peixes teleósteos
• Beneficiário: Renato Massaaki Honji
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/50918-1 - Desempenho comportamental em vertebrados ectotermicos: respostas as mudanças ambientais
• Beneficiário: Carlos Arturo Navas Iannini
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 08/57687-0 - Effects of global climate change of the Brazilian fauna: a conservation physiology approach
• Beneficiário: Carlos Arturo Navas Iannini
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático