[Zbrafish] Re: Zebrafish Age / Size Variations

[Tyrone]

On Aug 7, 9:02 pm, Oliver Braubach <braub... from dal.ca> wrote:

> I have been working on aspects of postembryonic development in the  
> zebrafish brain, and have been trying to determine a standard method  
> for 'aging' zebrafish. As many of you may be aware, the development of  
> individual fish varies greatly during the first month of development,  
> which ultimately leads to very noticeable differences in the size of  
> individual fish and their organs.

Hello Oliver,

I suggest you track down the papers by Markofsky et al concerning his
research on Nothobranchius guentheri. Growth is very important with
aging. It is commonly observed that "runt" fishes tend to live longer,
and thus, must age (accumulate aging-related pathologies) slower.
Markofsky didn't solve the problem of different growth rate, he simply
used a lot more specimens and let the stats even out the problem.

You may wish to explore different rearing conditions. My experience as
a aquarist has taught me that the larger the tank and the heavier the
feeding the better the growth rate and the more even the growth rate
in the brood.

Another option is to decide on a size cut off per age. For instance,
at day x you will only use "average +/- SD" size fish. This of course
means you will have to do carefully controled experiments monitoring
growth rate daily for a shoal of fry. This is easily acomplished with
behavioural software such as "Ethovision", where the fish are placed
in a tank that rests over some graph paper and the tank and fish
photographed. The program does the hard work. This is briefly
explained in Genade et al. Aging Cell. 4:223--233, 2005.

Hope this is of some help.

Kind regards