Just as an experiment, we wanted to see how fast we could turn
over a generation in zebra danios. Most of our conversations with
our customers (zebra fish researchers) indicated that they were
requiring 90 days or more to go from egg to new generation eggs.
Our commercial production was also running about 90 - 110 days
at 22-24 C, but we have no need for short generation times.
We set up three tanks. Tank C1 at 23-24 C was the control at a
density of 100/liter (1000 liter production tank) and the
experimental tanks at 8/liter (60 liter tanks) with one at 28 C and
the other at 22-23 C ( all 100K+ larva were from the same
The trick to getting the fast growth was 100% live feeds. We
started with protozoan culture and went to sifted moina (we have
some cultures of specific pathogen free live feeds -- wild live feeds
have a high risk of bringing in some nasty problem organism, don't
use the pet shop live feeds). The experimental tanks had
continuous live foods available. The systems were only serviced
(feed) once per day with tank cleanings once per week (most of our
customers seem to be spending too much effort on multiple
feedings of the tanks per day).
We got viable eggs (only a few hundred on the first try) on day 47
counting from the spawning date of the parents (not hatch date) for
the 28 C tank. The 22 C tank is now up to about 23-24 and needs
another week. We dropped the density to only about 1/liter on day
40. The overall survival was 79% in both experimental tanks from
Live feeds and low densities with excellent water quality could
almost double the productivity of some types of research where
you need very fast generation turnover to detect the impact of your
Dallas E. Weaver, Ph.D.
5542 Engineer Dr.
Huntington Beach Ca,
(714) 890 0138 deweaver at gte.net
(714) 890 3778 fax