increasing aeration and a fast water flow I have found strengthens larvae. lowering the water level to facilitate the surface also helps. Breeding the largest possible stock insures health as well as a rich green algae growth in hatching tank. I've observed numerous times clinging half way on the algae surface as if resting and latter continuing for the surface.
Stamatis VARSAMOS wrote:
> A 13:09 19/04/00 -0600, vous avez écrit : > > Fish-sci list members: > > > > We are attempting to study the effects of various chemicals on > > bluegill survival to approximately 20 days post hatch. However, we > > are experiencing near 100% mortality (in controls) at about 11 days > > after hatch (25C). Mortality seems to be due to lack of swim bladder > > inflation and switch from endogenous to exogenous nutrition (we are > > feeding marine rotifers). We have tried and are continuing to try > > various things to improve the situation but so far, no luck. Do any > > of you have procedures that might get us at least 50% control > > survival? Any suggestions/insight would be greatly appreciated. > > > > Thank you in advance. > > > > Diana Papoulias > > Hello, > > more info on your rearing conditions and setup might help us in > understanding what is going wrong. > Anyway, in sea bass and sea bream larval rearing, mortality due to swim > bladder malfunction (lack of inflation) was significantly reduced by > removing from the surface of the water in the rearing tanks, the oil film > introduced by the feeding (rotifers or artemia). > Hope it helps > cheers > > ps: By the way, can you see any preys (rotifers) in the intestin of the > larvae? > > ********************************************************** > > ° ° ><> ° > <>< ><> ° ><> > <>< ° ° ><> > ><> ><> ><> > ><> > M. Stamatis VARSAMOS ° > Laboratoire de Biologie Animale / cc 102 > Universite de Montpellier II ><> > ° Place Eugene Batailon ° ><> > <>< 34095 Montpellier Cedex 05 <>< > FRANCE > ° tel: +334 67 14 36 77 <>< ° ><> > <>< fax: +334 67 14 35 95 > e-mail: [log in to unmask] <>< > ° > ><> ° ><> ° > <>< ><> ><> > > ********************************************************** > > ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> > To leave the Fish-Sci list, Send blank message to: > mailto:[log in to unmask] > Vacation? send SET FISH-SCI NOMAIL to [log in to unmask] > ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><>
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