Seawater rotifer, cladoceran
and copepod culture
Aquaflow Technical Leaflet 2002-56
European Network for the Dissemination of Aquaculture
RTD Information (Q5CA-2000-30105) and previously FAIR-3837, URL: http://www.aquaflow.org/
Rotifers are a key point in the larvae food chain of a
lot of cultured species. Only two, Brachionus rotundiformis and Brachiounus
plicatilis, are used to feed commercial fish. Their sizes fluctuate between
150 and 260 µm and both are deficient in n-3 long chain fatty acids.
Therefore, it would be interesting to find smaller rotifers with a better
profile of fatty acids, since these would provide a more suitable food for
the nutritional requirements of cultured fish. In addition, there is a
distinct advantage of using smaller prey for those species that require
these sizes at the beginning of their feeding schedule.
The main objective of the project was to identify
alternative rotifer species and, if possible, cladoceran and copepod
species, that are capable of being used in aquaculture as live prey for
larval feeding. The authors of this research, in order to attain these
objectives, have isolated two coastal rotifers, Synchaeta cecilia valentina
and Synchaeta littoralis.
The researchers have successfully managed to rear both
species. S. cecilia valentina was fed with different monoalgal diets,
obtaining the best results when Tetraselmis sp. was used. The fatty acid
profile of S. cecilia valentina was also determined and show that this
species has a similar nutritional profile to Brachionus. S. littoralis was
also successfully reared using Tetraselmis sp. as food, after rejecting
other microalgae that previously showed poorer results than Tetraselmis. The
growth rate of both species was very interesting, with intrinsic growth rate
values at around r=1 day-1, which is similar to the intrinsic growth rate of
Brachionus. However there are problems related to culture instability,
mainly in the culture of S. cecilia valentina. At present work is continuing
in order to solve these problems.
The copepod and cladoceran culture demonstrates a
higher level of culture management problems and a poorer growth rate than
rotifers and further research is needed in order to get better results in
both areas.
For more information:
Dr. Rafael Oltra
Departamento de Microbiología y Ecología Edificio de Investigación
Facultad de Ciencias Biológicas Universidad de Valencia
Dr. Moliner 50 46100- Burjasot (Valencia)
Spain
Phone : +34 96 3864616
Fax : +34 96 3983099
E-mail : rafael.oltra@uv.es