Abstract
The supply of microalgae to hatcheries is often insufficient to meet the requirements of several batches of larvae for large-scale breeding of the sea cucumber Apostichopus japonicus. Larvae of the sea cucumber A. japonicus were exposed to different feeding regimes to evaluate the effects of temporary starvation on growth, survival and development. The total starvation was 2, 4 and 6 days, and each had two different timings for starvation. In all the treatments, the growth rates of larvae were not significantly affected by temporary starvation up to day 4, while they were significantly influenced from days 6 to 14 after hatching. For larvae that had been starved for 2 and 4 days, the percentages of late auricularia were 23.33, 36.67, 30.00 and 30.00%, which were higher than those of larvae starved for 6 days, which were 16.67 and 6.67%. For the starved group, larvae never developed beyond the mid-auricularia stage, having 43.33% of early auricularia and 56.67% of mid-auricularia. The survival rate of starved larvae decreased steadily and 100% mortality was observed up to day 14. On day 14, significantly lower survival rates of 7.78 and 28.89% were observed when larvae were starved for 6 days. To achieve high growth rates and fast development of auricularia and maximize larval survival in hatcheries, starvation of 6 days or more should be avoided at the early stage of development of the sea cucumber A. japonicus.
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark
Acknowledgements
The study was supported by the grants from the Scientific and Technical Supporting Program (2011BAD13B03), and Science and Technology Development Program of Shandong Province (2009GG10005013).
Notes
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark