Different responsive abilities of different types of eels (cultured, cultured feminized, and wild silver eels) during artificial maturation are recognized, and maturity status at the beginning of artificial maturation might be important. Maturity may represented by the distribution pattern of oocyte diameters. Androgens have been demonstrated to stimulate ovarian development in eels. To determine the initial status, operations were performed on eels to identify sex and to sample ovarian tissue. The recovered eels were then treated with 17α-methyltestosterone (17MT), and the responses of individual eels to 17MT were determined by the fold change in the mean oocyte diameter before and after treatment. Sampled ovarian tissues were fixed in Bouin's solution, oocytes were isolated, and the diameter of isolated oocytes was measured. The ovarian status, determined by kernel density estimation (KDE), was presented by the probability density of measured oocyte diameters; compared with histograms, a description method, KDE, provided more subtle information on the investigated ovary. Our data indicated a correlation between the initial ovarian status (density pattern) and the consequence of treatment (change of ovary); we also argued the semelparity of the Japanese eel. Our results supported the hypothesis that the initial ovarian status is an important factor affecting artificial maturation and that androgens could ameliorate the initial status of the eel ovary.

中文翻译：

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养殖鳗鱼卵巢状态与雄激素敏感性之间的相关性。

人们认识到在人工成熟过程中，不同类型的鳗鱼（培养的，培养的女性化的和野生的银鳗）具有不同的响应能力，并且在人工成熟开始时的成熟状态可能很重要。成熟度可以由卵母细胞直径的分布模式表示。雄激素已被证明可以刺激鳗鱼的卵巢发育。为了确定初始状态，对鳗鱼进行了手术以鉴定性别并采样卵巢组织。然后将回收的鳗鱼用17α-甲基睾丸酮（17MT）处理，并通过处理前后平均卵母细胞直径的倍数变化来确定单个鳗鱼对17MT的反应。将取样的卵巢组织固定在Bouin溶液中，分离卵母细胞，并测量分离的卵母细胞的直径。卵巢状态由籽粒密度估计（KDE）确定，由测得的卵母细胞直径的概率密度表示。与直方图相比，描述方法KDE提供了有关所研究卵巢的更多细微信息。我们的数据表明初始卵巢状态（密度模式）与治疗结果（卵巢变化）之间存在相关性。我们还论证了日本鳗鱼的同质性。我们的结果支持以下假设：卵巢的初始状态是影响人工成熟的重要因素，而雄激素可以改善鳗鱼卵巢的初始状态。提供了有关被调查卵巢的更多细微信息。我们的数据表明初始卵巢状态（密度模式）与治疗结果（卵巢变化）之间存在相关性。我们还论证了日本鳗鱼的同质性。我们的研究结果支持以下假设：卵巢的初始状态是影响人工成熟的重要因素，而雄激素可以改善鳗鱼卵巢的初始状态。提供了有关被调查卵巢的更多细微信息。我们的数据表明初始卵巢状态（密度模式）与治疗结果（卵巢变化）之间存在相关性。我们还论证了日本鳗鱼的同质性。我们的结果支持以下假设：卵巢的初始状态是影响人工成熟的重要因素，而雄激素可以改善鳗鱼卵巢的初始状态。