Departamento de Morfologia Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, P.O. Box 1686, CEP 30161-970 Belo Horizonte, Minas Gerais, Brazil.
Anim Reprod Sci. 2010 Apr;118(2-4):330-6. doi: 10.1016/j.anireprosci.2009.07.004. Epub 2009 Jul 23.
The present study evaluated for the first time sex steroid profiles and fecundity in females of Prochilodus argenteus from two sections of the São Francisco River Brazil, downstream from the Três Marias Dam, which influences characteristics of their water habitat. The model species in the study, P. argenteus, is an important commercial and recreational species in Brazil. In the region closest to the dam (section 1), females did not reach final oocyte maturation, failed to spawn, and displayed lesser circulating concentrations of testosterone, 17(-hydroxyprogesterone (17(-P) and 17beta-estradiol (E2) than those farther downstream of the dam (section 2). The endocrine and fecundity deficiencies probably are attributed to lower water temperature and oxygen concentration in (section 1). The follicular atresia rate in the region closest to the dam (26%) was greater than those fish captured farther downstream of the dam (13%), after the Abaeté River (section 2). Variations in testosterone, E2 and 17(-P concentrations in section 2, followed gonadal maturation which are typical features of species which have seasonal reproduction, group-synchronous oocyte development, and are single batch spawners such as P. argenteus. Results document the first evidence of endocrine and reproductive dysfunctions caused by inadequate water conditions in a wild population of the migratory species P. argenteus in the São Francisco River, downstream from the Três Marias dam.
本研究首次评估了来自巴西圣弗朗西斯科河两段的银斧鱼（Prochilodus argenteus）雌鱼的类固醇激素谱和生殖力，该河下游有三马林加大坝，影响其水栖息地的特征。研究中的模式物种银斧鱼是巴西重要的商业和娱乐性物种。在离大坝最近的区域（第 1 节），雌鱼未能完成终末卵母细胞成熟、产卵，且循环中的睾酮、17-羟孕酮（17-P）和 17β-雌二醇（E2）浓度低于大坝下游更远的区域（第 2 节）。内分泌和生殖缺陷可能归因于（第 1 节）较低的水温和氧气浓度。离大坝最近的区域（26%）的卵泡闭锁率高于大坝下游更远的区域（13%），在阿巴埃特河（第 2 节）之后。第 2 节中睾酮、E2 和 17-P 浓度的变化伴随着性腺成熟，这是具有季节性繁殖、群体同步卵母细胞发育和单次产卵的物种的典型特征，如银斧鱼。结果首次证明了三马林加大坝下游圣弗朗西斯科河洄游性银斧鱼野生种群因水条件不足而导致的内分泌和生殖功能障碍。
