Lophiosilurus alexandri is a freshwater carnivorous fish for which there is fishing pressure in its natural environment, yet the species has potential for captive rearing. Information on growth and sexual development for the species is scarce, and age and size at first maturation have yet to be determined. A total of 400 fish, therefore, were reared from hatching to 968 days after hatching (DAH). Fish gonads were histologically analyzed throughout the rearing period, and growth, the hepatosomatic index and the gonadosomatic index were compared between males and females. Estradiol, testosterone and 17α-hydroxyprogesterone concentrations were quantified at 845 and 968 DAH to compare sexually mature males and females. Weight and length did not differ between males and females (P >  0.05). Males were sexually mature at 593 DAH, with body lengths of 29.88 ± 1.76 cm and weights of 444.1 ± 77.03 g, while females were sexually mature at 845 DAH, with lengths of 36.51 ± 1.06 cm and body weights of 783.05 ± 48.57 g. The results provided important information regarding the minimum capture size of L. alexandri for identifying the appropriate period to begin reproductive management of the species.

中文翻译：

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Lophiosilurus alexandri（Steindachner，1876）在受控条件下的饲养和成熟：首次报道和未来展望。

Lophiosilurus alexandri是一种淡水肉食性鱼类，其自然环境中存在捕捞压力，但该物种具有圈养的潜力。关于该物种的生长和性发育的信息很稀少，并且第一次成熟时的年龄和大小尚未确定。因此，总共有400条鱼从孵化到孵化后968天（DAH）。在整个饲养过程中对鱼的性腺进行组织学分析，并比较雌雄之间的生长，肝体指数和性腺体指数。雌二醇，睾丸激素和17α-羟基孕酮的浓度分别在845和968 DAH进行定量，以比较性成熟的男性和女性。男性和女性之间的体重和长度没有差异（P> 0.05）。男性在593 DAH时性成熟，体长为29.88±1.76厘米，体重为444.1±77.03 g，而雌性性成熟时间为845 DAH，体长为36.51±1.06 cm，体重为783.05±48.57 g。结果提供了有关亚历山大紫苏的最小捕获量的重要信息，可用于确定开始对该物种进行生殖管理的适当时期。