Here is my recommendation for containing Coleps and/or any other
1. Bleach all of your eggs as soon as possible. If needed, you can
reference the egg bleaching protocol found in The Zebrafish Book, [Only registered users see links. ] or on our website, [Only registered users see links. ].
2. Be sure to remove ALL dead/damaged eggs before bleaching.
3. After bleaching, keep your embryos in embryo media until they
have inflated their swim bladders and are swimming. Zebrafish larvae
are the most susceptible when they have hatched, but not yet inflated
their swim bladders. Once the larvae are able to swim properly, they
can fend off most organisms.
If you haven't already positively identified the organisms and would
like to, I recommend putting a few of these critters on a slide and
look at them under a compound microscope. Coleps are quite small and
move in an intense twirling motion. They have plates that cover
their exterior and make them look like hand grenades. As you
mentioned, they are voracious and can consume an entire embryo in 45
For future reference, I recommend obtaining a good protozoa picture
book/guide. We have 2 older books that are quite helpful, however
you might be able to find some newer better books with even better
pictures and information.
- Patterson, D.J. (1996). Free-Living Freshwater Protozoa (A Colour
Guide). John Wiley & Sons Inc., New York, New York.
- Berk, S. G.; Gunderson, J. H (1993). Wastewater Organisms (A Color
Atlas). CRC Press LLC.
If you continue to have problems, please let me know.
On Feb 9, 2009, at 4:17 PM, Fresquez, Theresa, DCA wrote:
April R. Freeman (Mazanec)
Zebrafish Int.'l Resource Center
5274 University of Oregon
Eugene, OR 97403-5274