ABSTRACT This study describes for the first time the early gonadal morphogenesis and raises the possibility of occurrence of protandric hermaphroditism in the Mexican snook (Centropomus poeyi). To achieve this, histological analysis of early gonadal differentiation was performed in 105 juvenile specimens ranging from 136 to 367 days post-hatching (dph). The early gonadal differentiation of the Mexican snook started at 178–213 dph and was completed at 355–367 dph. Active spermatogenesis was observed at 355–367 dph, once the compartmentalization of testis in germinal and interstitial compartments was accomplished. Our study demonstrates that in the Mexican snook, early gonadal differentiation is directed to produce 100% males, implying protandric hermaphroditism and showed the presence of a long-lasting period of gonadal differentiation, which makes this species highly sensitive to environmental cues.

中文翻译：

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墨西哥斯努克 Centropomus poeyi (Centropomidae, Perciformes, Teleostei) 的早期性腺分化表明前体雌雄同体

摘要 本研究首次描述了早期性腺形态发生，并提出了墨西哥斯努克 (Centropomus poeyi) 发生前体雌雄同体的可能性。为实现这一目标，在孵化后 (dph) 136 至 367 天的 105 个幼鱼标本中进行了早期性腺分化的组织学分析。墨西哥斯努克的早期性腺分化开始于 178-213 dph，并在 355-367 dph 时完成。在 355-367 dph 时观察到活跃的精子发生，一旦睾丸在生发和间质隔室中的划分完成。我们的研究表明，在墨西哥斯努克，早期的性腺分化旨在产生 100% 的雄性，这意味着前体雌雄同体，并表明存在长期的性腺分化，