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This is especially true in case of \u201ccritically endangered\u201d species, like the European eel (<jats:italic>Anguilla anguilla<\/jats:italic>), whose life cycle is not closed yet, leading to the necessity of capturing younglings from natural populations for both research and productive purposes. Despite androgens being involved in spermatogenesis and playing pivotal roles in the pre-migratory morphological and physiological changes, their quantification in different biological tissues is still to be refined in European eels. The aim of this study was to evaluate the feasibility of extraction and quantification of testosterone (T) and 11-ketotestosterone (11-KT) from male European eel milts. The secondary aim was to investigate potential differences in androgens\u2019 profiles and\/or functional characteristics of spermatozoa between wild-caught and farmed specimens. Twenty-four male European eels obtained from the North Adriatic region (14 wild-caught and 10 farmed) underwent a maturation-inducing hormonal treatment for milt production; blood and milt samples were then collected for androgens quantification upon ELISA and RIA methodologies. Spermatozoa were also evaluated for viability and objective motility. Plasma showed average T and 11-KT levels of 2.32 and 6.88 ng\/mL, respectively, while milt 0.24 (T) and 1.09 ng\/mL (11-KT). Significantly higher spermatozoa concentrations and motility were observed in farmed eels\u2019 milts. This work contributes to deepening the knowledge on teleost physiology, being the first report quantifying T and 11-KT from European eels\u2019 seminal plasma and comparing the quality of milts of farmed vs wild specimens.\n<\/jats:p>","DOI":"10.1007\/s10695-025-01494-y","type":"journal-article","created":{"date-parts":[[2025,4,8]],"date-time":"2025-04-08T10:57:46Z","timestamp":1744109866000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Milt androgen profile and evaluation of sperm morpho-functional characteristics of wild-caught and farmed European eels (Anguilla anguilla)"],"prefix":"10.1007","volume":"51","author":[{"given":"Laura","family":"Gentile","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B\u00e1lint L\u00f3r\u00e1nt","family":"Hausz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Casalini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nadia","family":"Govoni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pietro","family":"Emmanuele","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Albamaria","family":"Parmeggiani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Domenico","family":"Ventrella","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Laura","family":"Bacci","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oliviero","family":"Mordenti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Elmi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,4,7]]},"reference":[{"key":"1494_CR1","doi-asserted-by":"publisher","first-page":"285","DOI":"10.1016\/0305-0491(84)90027-0","volume":"79","author":"S Abraham","year":"1984","unstructured":"Abraham S, Hansen HJ, Hansen FN (1984) The effect of prolonged fasting on total lipid synthesis and enzyme activities in the liver of the European eel (Anguilla anguilla). 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