Sex steroid hormones are important players in the control of sex differentiation by regulating gonadal development in teleosts . Although estrogens are clearly associated with the ovarian differentiation in teleosts , the effects of androgens on early gonadal development are still a matter of debate . Traditionally , 11 - ketotestosterone (11 - KT) is considered the major androgen in fish ; however , 5α - dihydrotestosterone (5α - DHT) , the most potent androgen in tetrapods , was recently found in fish testis and plasma , but its physiological role is still unknown . In this context , the expression of genes associated with steroidogenesis and spermatogenesis , body growth and sex differentiation were assessed in Odontesthes bonariensis larvae fed with food supplemented with two doses of 5α - DHT (0 . 1 and 10 μg / g of food) from hatching to 6 weeks of age . At the lowest dose , 5α - DHT treated larvae showed an estrogenic gene expression pattern , with low hsd11b2 and high cyp19a1a and er2 expression levels with no differences in sex ratio . At the highest dose , 5α - DHT produced a male - shifted sex ratio and the larvae exhibited a gene expression profile characteristic of an advancement of spermatogenesis , with inhibition of amh and stimulation of ndrg3 . No differences were observed in somatic growth . These results suggest that in this species , 5α - DHT could have a role on sex differentiation and its effects can differ according to the dose .
CITATION STYLE
Begon, M., Howarth, R. W., & Townsend, C. R. (2017). Geburt, Tod und Wanderbewegungen. In Ökologie (pp. 155–193). Springer Berlin Heidelberg. https://doi.org/10.1007/978-3-662-49906-1_5
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