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Re: Sex ratios and water
Hi,
It was all info on sex ratio. The book has some 30 pages on killies,
describing in details most popular species. In general, we most
interestin thing about book (not killies only) is that recommended tank
volume for different species is generally 3-4 times less then anything
recommended in US. And I know in Russia 10g was considered VERY large.
Best
Lilia
On Tue, 14 Jul 1998, Al & Lana Anderson wrote:
> I find the translations interesting I wonder if you could post more of them.
>
>
> BREED YOUR FISH
> TODAY MAN'S OVER
> POPULATION IS KILLING
> THE WILD SUPPLY
> 1819967 ICQ NUMBER
> -----Original Message-----
> From: Lilia Stepanova <ls691035 at bcm_tmc.edu>
> To: killietalk at aka_org <killietalk at aka_org>
> Date: Monday, July 13, 1998 10:49 PM
> Subject: Re: Sex ratios and water
>
>
> >
> >Hi,
> >Here is some info from book published in Russian (A.S.Polonskii
> >"Soderjanie i razvedenie aquariumnih rib", 1991).
> >
> >"Temperature and chemical composition of the water can affect sex ratio
> >in the fry of Cyprinodontidae. For example, at t=22-25 C most of the fry
> >will be females, if the temperature is not constant, most of the fry will
> >be males. At the same pH=6.0, E.dageti will have more female offspring
> >(>90%) in the soft water (dH about 5 degrees), in the hard water (dH 24)
> >about 90% of fry will be males. A.gabunense in the acidic water (pH 5.0)
> >will give more females, at higher pH=6.5 - more males."
> >
> >Cheers,
> >
> >
> >Lilia
> >
> >On Mon, 13 Jul 1998 elyj at liddellsapp_com wrote:
> >
> >> I was interested to read of Sam's experiment about pH and sex ratios.
> >> Sam (or anyone else), did you try hatching the eggs in water of differing
> >> pH and seeing what ratios you get? I think you said you hatched all eggs
> >> in one type of water and then transferred the fry to different water. A
> >> way to get some idea whether water conditions cause an actual shift in
> >> gender or simply that certain conditions are better suited to one sex
> might
> >> be to monitor the percentage of eggs that hatch and grow to adulthood. If
> >> a large number of eggs don't hatch, or don't hatch into vigorous fish, it
> >> may indicate the latter is true. On the other hand, if a consistent
> number
> >> of eggs hatch under different conditions, but produce varying sex ratios,
> >> it may indicate some gender shifting. Further, what about the possibility
> >> that the water in which spawning takes place is a factor? That is, maybe
> >> fertilization rates are higher for one sex under certain conditions. I
> would
> >> be interested in any thoughts anyone has on these topics. Of course, all
> >> this may be totally off-base, but it would be interesting to know that as
> >> well.
> >>
> >>
> >
>
>
References: