RE: [Killietalk] Diapause, Development, and Hatching of Annual Eggs

["Mark Pearlscott" <mark at pearlscott_com>]

Bob and Lee,

Thank you both very much for your reply.  They have both been very
informative.  I will add both your comments (and others as they come in) to
the summary and repost it in the near future.

In the meantime... If what Bob say is true (about an increase of CO2 being
the trigger to hatch from D3, and the trigger is not anaerobic
conditions)...

One could theoretically create a small hatching set up as follows:
1) A small container which will hold the eggs.
2) Add a CO2 bubble line to the container and bubble it slowly.
3) Add an airline to the container and bubble it slowly.
4) Add peat tea (and/or peat).
5) Add the D3 eggs.

My thinking is that the airline would make sure that sufficient oxygen is
present in the water, while the CO2 line would maintain a higher than normal
CO2 level.  I would imagine that the airline would be causing some of the
added CO2 to be driven off, but maybe the two bubbling lines could be
adjusted in relation to each other.  This setup might be a very efficient
method for hatching and also by making sure sufficient oxygen is present
might prevent belly-sliders (or at least lessen their numbers).

Does anyone have any thoughts about this, or has tried something like this?
It sounds like a new experiment for me to try.

Thanks again Bob... great info!

Cheers,

Mark
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Mark Pearlscott, killifish addict.
A Member of:
AKA - http://www.aka.org
NWK - http://nwk.aka.org
PSK - http://groups.yahoo.com/group/pugetsoundkillies/
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
> 
> Hello Mark - After just one year, you're much better informed than many
> people who have been in the AKA for decades. Well done. With regard to
> hatching (feel free to correct me, youse guys), it's not anaerobiasis that
> induces hatching, but an increased concentration of carbon dioxide.
> (that's
> why blowing bubbles with a straw works - the oxygen remains about the same
> but the CO2 is increased).  CO2 stimulates the hatching glands in the
> throat
> to release the enzyme chorionase. The chorionase dissolves the inner
> layers
> of the chorion (egg shell), so that it swells and weakens as water enters
> the chamber. Finally, the exertions of the embryo (prolarva or larva)
> split
> the weakened shell and the fry escapes. A prolarva is not fully developed,
> but a larva is. Generally killifish hatch as larvae, while tetras,
> american
> minnows, danios, barbs and bubblenester anabantoids hatch as prolarvae. -
> Bob Goldstein
> 




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