[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Killietalk] Diapterons: defect genetic or enviroment
This is real old and I couldn't put my finger on it easily. I'm copying
Bruce Turner who probably knows about this as well. There were many old
papers on Fundulus and Cyprinodon showing diminishing numbers of vertebrae
with latitude (I don't recall in which direction) and that was explained as
not a subspecies characteristic but a temperture effect in the old
physiological literature. - Bob G.
----- Original Message -----
From: "Barry Cooper" <bjc3 at centurytel_net>
To: "killifish discussion list" <killietalk at aka_org>
Sent: Friday, August 03, 2007 12:57 PM
Subject: Re: [Killietalk] Diapterons: defect genetic or enviroment
>I have seen the same phenomenon is a couple of species of
> Nothobranchius. It was very frustrating because it caused me to lose one
> particularly desirable species. I have seen in recently in a second
> species. The the latter case I hatched quite a few different species at
> the same time and all the others appear to be normal.
>
> A friend reported to me that he had seen the same thing and that he
> attributed it to low temperatures. I think he did that out of trial and
> error, finding that increasing temperature prevented the effect. It is
> interesting to think about the possibility that the low temperature
> causes either loss of vertebrae of shortening of vertebrae. Bob, I'd be
> very interested in knowing the references if you have them available. I
> would think that the effect would have to occur during development of
> the embryo, that is during incubation of the eggs, rather than at the
> juvenile stage, if the loss of vertebrae effect is true. I would have to
> think that fish don't produce extra vertebrae after hatching.
>
> Another friend has the same species in which I first saw this problem.
> He incubates his eggs at a controlled temperature while mine are
> incubated on shelves high up in my fishroom. The latter is kept in the
> low to mid 70s so the temperature up there should be mid to high 70s.
> However, it could fluctuate during the year and could result in sporadic
> occurrence of this problem. Food for thought. Maybe it's time to build
> an incubator.
>
> Interesting thoughts. I'd like to hear whether others have had this
> experience.
>
> Barry
>
> Barry J. Cooper
> Sweet Home, OR 97386
>
>
>
> Robert Goldstein wrote:
>> There is scientific literature that correlates colder temperatures with
>> fewer vertebrae in killifishes, and vitamin deficiencies with bent spines
>> in
>> many fishes. Correlations are not proof of cause and effect, but they
>> should be considered.
>>
>> ----- Original Message -----
>> From: "Miguel Angel" <misaher at yahoo_es>
>> To: "lista AKA" <killietalk at aka_org>
>> Sent: Friday, August 03, 2007 9:24 AM
>> Subject: [Killietalk] Diapterons: defect genetic or enviroment
>>
>>
>>
>>> I keep for two years Diap. Georgiae 95 Essongville without problems.
>>> They
>>> spawn, hatch well the eggs and they developed more or less normally. I
>>> also
>>> have Diap. Cyanostictum from 2006 november.
>>>
>>> Some young of georgiae and cyanostictum that was born at 2006 November
>>> are
>>> "short". The aspect of the fish is like an adult but its form is like if
>>> we compress it the length, keeping the height. More or less their length
>>> is around 2-2,5cm. They are healthy but abnormally short. They reminds
>>> me
>>> when years ago a friend talk me about the killis "bonsai".
>>>
>>> Reading something of information that there is at internet, somebody
>>> attributes to low temperatures during the juvenile time the fact that
>>> they
>>> cut the growth and stay small. Other attributes it to the inbreedings
>>> with brothers. It says to the increase on infertility and the fish to
>>> stay
>>> small.
>>>
>>> Those born in November are the first generation of reproduced Diap.
>>> georgiae. The cyanostictum comes from some eggs that a friend give me.
>>> The
>>> hypothesis that the low temperatures causes "dwarfism" can be true
>>> because
>>> some georgiae from 2006 June (first generation) are perfect.
>>>
>>> As control group I have some georgiae fry (2ª generation) and fulgens
>>> (1ª
>>> generation) that were born me in March. For the moment, their aspect is
>>> normal, lengthened and fine. We will see that it happens when I breed
>>> the
>>> "short" cyanostictum and georgiae. I will see that it occurs to the fry;
>>> if they "dwarfism" is heredity or if they will have a good development.
>>> I
>>> must maintain the temperature since they born at 23-24ºC. to discard the
>>> influence of the low temperature.
>>>
>>>
>>> Did somebody happen something similar? Up to now I never see on my
>>> breeding killis symptoms of "dwarfism". It is certain that the fish
>>> developed in small aquariums usually have less size than those that have
>>> grow in big aquariums. But this affects to the general aspect and the
>>> obtained fish are proportional and not compressed lengthwise.
>>>
>>> Any comment is appreciated
>>>
>>> Best wishes from Spain
>>> Miguel Angel Saiz
>>> www.misaher.es
>>>
>>>
>>>
>>> ____________________________________________________________________________________
>>> Sé un Mejor Amante del Cine
>>> ¿Quieres saber cómo? ¡Deja que otras personas te ayuden!
>>> http://advision.webevents.yahoo.com/reto/entretenimiento.html
>>>
>>> Join the AKA at http://www.aka.org/aka/modules/content/index.php?id=9.
>>> Archives are at http://fins.actwin.com/killietalk/
>>> Modify your subscription at
>>> http://www.actwin.com/mailman/listinfo.cgi/killietalk
>>>
>>>
>>
>>
>> Join the AKA at http://www.aka.org/aka/modules/content/index.php?id=9.
>> Archives are at http://fins.actwin.com/killietalk/
>> Modify your subscription at
>> http://www.actwin.com/mailman/listinfo.cgi/killietalk
>>
>>
>>
>
> Join the AKA at http://www.aka.org/aka/modules/content/index.php?id=9.
> Archives are at http://fins.actwin.com/killietalk/
> Modify your subscription at
> http://www.actwin.com/mailman/listinfo.cgi/killietalk
>
Join the AKA at http://www.aka.org/aka/modules/content/index.php?id=9.
Archives are at http://fins.actwin.com/killietalk/
Modify your subscription at http://www.actwin.com/mailman/listinfo.cgi/killietalk