Does the rainbow trout ovarian fluid promote the spermatozoon on its way to the egg?

Vitaliy Kholodnyy, Borys Dzyuba, Marek Rodina, Hermes Bloomfield-Gadêlha, Manabu Yoshida, Jacky Cosson, Sergii Boryshpolets

Research output: Contribution to journalArticle (Academic Journal)peer-review

4 Citations (Scopus)
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The fertilization of freshwater fish occurs in an environment that may negatively affect the gametes; therefore, the specific mechanisms triggering the encounters of gametes would be highly expedient. The egg and ovarian fluid are likely the major sources of these triggers, which we confirmed here for rainbow trout (Oncorhynchus mykiss). The ovarian fluid affected significantly spermatozoa performance: it supported high velocity for a longer period and changed the motility pattern from tumbling in water to straightforward moving in the ovarian fluid. Rainbow trout ovarian fluid induced a trapping chemotaxis-like effect on activated male gametes, and this effect depended on the properties of the activating medium. The interaction of the spermatozoa with the attracting agents was accompanied by the “turn-and-run” behavior involving asymmetric flagellar beating and Ca2+ concentration bursts in the bent flagellum segment, which are characteristic of the chemotactic response. Ovarian fluid created the optimal environment for rainbow trout spermatozoa performance, and the individual peculiarities of the egg (ovarian fluid)–sperm interaction reflect the specific features of the spawning process in this species.
Original languageEnglish
Article number9519
JournalInternational Journal of Molecular Sciences
Issue number17
Publication statusPublished - 1 Sept 2021

Bibliographical note

Funding Information:
Funding: The study was financially supported by the Ministry of Education, Youth and Sports of the Czech Republic projects—“CENAKVA” (LM2018099) and “Biodiversity” (CZ.02.1.01./0.0/0.0/16 _025/0007370), by the Grant Agency of the University of South Bohemia in Ceske Budejovice Int.J.Mol.Sci.2021, 22,xFORPEE(125/2016/Z,R REVIEW 013/2018/Z, and 097/2019/Z) and by the Czech Science Foundation (18-12465Y).22 of 25

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© 2021 by the authors. Licensee MDPI, Basel, Switzerland.


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