I have enjoyed looking back at this thread which to me is the essence of
the reason why associations like ANGFA, IRG and RSG were formed in the
first place. We came aware of the existence of these "Jewels of Sahul"
because of beautiful colour photos of theses fish. Those photos depicted
wild types
and looking as good as they do when they are feeling good e.g. spawning,
Everybody knows that rainbowfish show a wide range of colours and
brightness that varies between idividuals, local populations, subspecies
etc as well as the contentment and mood of the individual fish.
No matter how careful we are with our selection of breeders for the next
generation every time we breed them in the limited numbers ( from the
limited numbers of breeders that we use each time) we lose some of the
genetic diversity of that gene pool.Even when we select for wild-type
appearance we have no guarantee that the metabolic "fitness" of the line we
are producing is as good as the original stock and we don't have a reliable
easy way of measuring this except in a superficial way by the vigour,
fertility and longevity of the line we are producing.
I guess what I am trying to say is that I agree generally with Cary that we
should try to stick to the wild type as our model for appearance but please
try to check those 3 metabolic parameters regularly. I know that husbandry
techniques play a major part in this but there's not much point to a line
that looks right but dies out because of poor fertility.
What can we do in terms of practical advice to breeders? Breed from your
oldest generation for as long as you can ( since each has most likely got
potentially more genetic diversity than the next) but try to group spawn
with as close to equal numbers of each sex as possible ( since the genetic
contribution from each parent is equal) to avoid ending up with a
strain/line that has too strong a genetic component derived from our
practice of using only one male and several females.
Finally (at last) remember that keeping them right is supremely important
and right food, water conditions, temperature, lighting, age,
planting/display arrangement etc are probably more important than we give
credit for in contributing to the spectacular display that impressed you in
that original photo. And there is one more thing too - timing. Those
beautiful colours are only there intermittently and you have to be there
at the time to see them - the fish doesn't see the owner out there and
think, " there's the boss, I better put on a display or he'll feed me to
the Coal Grunter!" The real challenge for the top fish photographer is
knowing how to trigger the best display out of the fish when he has the
camera ready.
There are some fish that are still to be shown at their best - Pseudomugil
cyanodorsalis is a classic example. I have yet to see a good hot of a male
with fins flared and the bright golden lower half of the body switched on.
So before you reject the fish you have already spend a few months trying to
give them optimum treatment and look at them - especially a half hour or so
after the lights come on. You might be surprised.
Regards,
Bruce.
bhansen at ozemail.com.au
----------
> From: Mach Fukada <tuhoitc at aloha.net>
> To: rainbowfish at pcug.org.au
> Subject: Re: [RML] Looking for bright Rainbows
> Date: Saturday, 11 October 1997 17:24
>
> Cary and all of the RML,
> this does bring up a question in my mind. If we do this kind of
> culling are we artificially selecting strains of bows and thereby loseing
> some genetic variability?