Induction to maturation of the sea urchin Paracentrotus lividus (Lamarck, 1816) under laboratory conditions

Abstract

Laboratory experiments were carried out over two different periods, with the aim of investigating and utilizing the induction to gonadal maturation of the sea urchin Paracentrotus lividus. The final objective was to obtain viable gametes outside the period of natural spawning in the environment; which would allow the utilization of ecotoxicological bioassays with sea urchin larvae at any time of the year. The experiment consisted of maintaining some sea urchins in tanks and providing them with a natural photoperiod, unlimited food and a constant temperature of 20 °C. During days 0, 30, 60 and 90, gonads from 15 of these sea urchins were compared with those collected simultaneously in the natural environment. The gametes obtained were used to carry out fecundations, in order to check their viability. The final results obtained were clearly influenced by the gonadal state of the sea urchins at the initial stage of the experiment. The best results were obtained within a time period of 60 days and when the initial gonad index was low.

Keywords:

• gamete availability
• gonad maturation
• gonadal indices
• Paracentrotus lividus
• sea urchin

Acknowledgements

This study was supported by Project Fit‐310100‐2006‐7, funded by the Spanish Ministerio de Industria y Comercio; a contract to J.M. Garmendia, by the MEC programme Torres Quevedo (PTQ04‐3‐0597); and a grant to I. Menchaca (Technological Centre Foundation, Basque Government). We wish to thank Professor Michael Collins from the School of Ocean and Earth Sciences, University of Southampton (UK), and AZTI‐Tecnalia (Spain), for kindly advising us on some details of the manuscript. This paper is contribution number 471 from AZTI‐Tecnalia (Marine Research Division).