Gonadal development period and sexual differentiation through histological analysis in Brycon orbignyanus (Valenciennes, 1850) (Characiformes: Bryconidae)

Zardo, Éverton Luís; Fornari, Darci Carlos; Giora, Julia; Rotili, Daniel Antonio; Gomes, Itamar Cossina; Esquivel-Muelbert, Juan R.; Streit, Danilo Pedro

doi:10.1016/j.aquaculture.2021.736636

Cited by 7 publications

(7 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Piracanjuba ( B . orbignyanus ) has been described as a species with sex differentiation with direct gonochoristic development (Zardo et al, 2021), and both in aquaculture (Baldisserotto & Gomes, 2005; Zardo et al, 2021) and in natural environments (Vaz et al, 2000), the sex ratio identified for the species was 1♀:2♂. In this study, we corroborate that the final sex ratio in B .…”

Section: Discussionmentioning

confidence: 99%

“…marmoratus is a sequential diandric hermaphrodite (Lo Nostro & Guerrero, 1996) and B . orbignyanus is considered a direct gonochorist (Zardo et al, 2021), both species present the same pattern of sex differentiation in females, primary males and secondary males, even in the characteristics of remodelling of the gonadal tissue during sexual inversion involving the basement membrane.…”

Section: Discussionmentioning

confidence: 99%

“…The fact that B. orbignyanus does not have specific sex chromosomes makes the species more susceptible to influences from exogenous cues related to sex differentiation events, including stressors linked to cultivation (Fernandino & Hattori, 2019). (Baldisserotto & Gomes, 2005;Zardo et al, 2021) and in natural environments (Vaz et al, 2000), the sex ratio identified for the species was 1♀:2♂. In this study, we corroborate that the final sex ratio in B. orbignyanus is 1♀:2♂; however, we found that the sex ratio fluctuates over the period of sex differentiation due to the existence of secondary males within the population.…”

Section: Eleven Months-one Year Of Age: Sexual Maturitymentioning

confidence: 99%

“…There is temporal variation in the period of sex differentiation between fish species; however, this temporal variation can also occur in different populations of the same species according to the cultivation conditions (Fernandino & Hattori, 2019). In a study using fish farm animals, Zardo et al (2021) analysed the first year of life of B. orbignyanus with monthly collections and only identified the first signs of sex differentiation at nine months of age, while in this study, at six months of age, all individuals in the population were differentiated. The studies differ in relation with fluctuations in water temperature and population density in which the fish were kept, which demonstrates that the distinctions in animal management alter the labile period for sex differentiation during aquaculture.…”

Section: Eleven Months-one Year Of Age: Sexual Maturitymentioning

confidence: 99%

“…Brycon orbignyanus was originally described as a species that presents with sex differentiation with direct gonochoristic development, with a sex ratio of 1♀:2♂ (Zardo et al, 2021). However, the details of the morphological and temporal characteristics of the species' sex differentiation remain unclear, requiring detailed clarification of the events of sex differentiation that explain these proportions.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Female sex inversion as a reason for an unbalanced sex ratio in the neotropical species Brycon orbignyanus

Quirino

Delgado

Gomes‐Silva

et al. 2021

Aquaculture Research

View full text Add to dashboard Cite

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°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♀:2♂. 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.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%