A sperm competition model for the European bitterling (Rhodeus amarus)

0397413 - ÚBO 2014 RIV NL eng J - Journal Article
Smith, Carl - Reichard, Martin
A sperm competition model for the European bitterling (Rhodeus amarus).
Behaviour. Roč. 150, č. 14 (2013), s. 1709-1730. ISSN 0005-7959. E-ISSN 1568-539X
R&D Projects: GA ČR GA206/09/1163
Institutional support: RVO:68081766
Keywords : Acheilognathinae * alternative mating tactics * mating system * sneaking * sperm competition * sperm motility
Subject RIV: EG - Zoology
Impact factor: 1.401, year: 2013

Sperm competition occurs when the spermatozoa of one male coincide with those of another to fertilise the same eggs. In some taxa males perform multiple ejaculations, which may function in sperm competition or in maintaining a baseline density of spermatozoa in the female reproductive tract to ensure fertilisation, a process that has been termed "topping up". We investigated multiple ejaculations in the European bitterling (Rhodeus amarus), a freshwater fish that oviposits in freshwater mussels. We quantified spermatozoa in the mussel mantle cavity following ejaculation, and measured sperm motility parameters of males adopting different mating tactics. Following ejaculation spermatozoa density in the mussel increased linearly, peaked after 30 s, and then declined exponentially. Spermatozoa motility parameters did not differ between male mating tactics. We parameterised a model of sperm competition for R. amarus, which accurately predicted male fertilisation probability. We discuss these results in the context of multiple ejaculations and male mating tactics.
Permanent Link: http://hdl.handle.net/11104/0224983