Cristatus group egg problem - a legend?

[uwe]

Hi,

since several years there is a statement around, that due to a genetic defect 50% of Tr. cristatus/carnifex/dobrigicus/marmoratus eggs should die.

As I don´t believe everything in literature, I would like to proof or disproof this hypothesis. Therefore I separated randomly some eggs of my Tr. karelenii and see, if I can find a certain percentage of "non-developer".

Maybe some breeders of the other species would like to join this little project and seperately raise a certain number of random eggs.

See you

uwe

 

[Azhael]

My T.dobrogicus most definitely experience this phenomenon. I have never heard of any Triturus breeding group that doesn´t but it would be interesting to see if for some mutation, there are some that don´t.

 

[caleb]

An abstract of the original research (from 1980) can be seen here:
SpringerLink - Journal Article

Basically they must carry two different versions of a particular gene- they'll die in the egg if they have two identical versions.

 

[uwe]

Thanks Caleb for the article (I had it already).

My point would be checking out the different kinds of former cristatus group (which is summed up in the article from 1980).

I will do that for the karelinii species I breed at the moment.

Uwe

 

[vide]

Hi Uwe,
I was thinking along the exact same lines. So when my T.marmoratus started laying a few weeks ago I started gathering data. The trend indicates it is true that 50% die but I will get back to you when I am finished with my little experiment.

Cheers,
Vide

 

[Azhael]

If the experiment is about the former Triturus, then the answer is easy. Only the current Triturus are affected. Lissotriton and Ichthyosaura are not. Their lineages separated from that of Triturus before the chromosomal condition appeared.
So basically the only ones affected are T.marmoratus, T.pygmaeus, T.cristatus, T.carnifex, T.karelinii, T.dobrogicus and T.macedonicus.

I see you still use the old classification which includes Lissotriton and Ichthyosaura in the genus Triturus. If you look at the new -which is in fact also the old- classification, it becomes very clear.

 

[vincent]

So if you cross any of the crested / marbles with in their group there survival should be better the question then arises are they hybrids or are they integrades and if you cross them back with each other would the egg hatching rate improve. My friend last year had over 500 Great Crested Newt eggs in his pond not one started to develop. He provides strips of plastic for them to lay on plus he can monitor the success or failure of the eggs year by year.Last year was a wash out. I breed T Carnifex and this year the number of duff ones is a lot less than 50% however I think half the time its the size of the container you keep the eggs in and the quality of the water, that stops fungus from affecting good eggs If you have it in your mind anyway that you are going to lose 50%of them maybe you don't try as hard as you should ie water quality and fungus inhibitor

 

[uwe]

Hi Uwe,
I was thinking along the exact same lines. So when my T.marmoratus started laying a few weeks ago I started gathering data. The trend indicates it is true that 50% die but I will get back to you when I am finished with my little experiment.

Cheers,
Vide

Hi Vide,

it would be great to have this data.

Uwe

 

[uwe]

My friend last year had over 500 Great Crested Newt eggs in his pond not one started to develop. He provides strips of plastic for them to lay on plus he can monitor the success or failure of the eggs year by year.Last year was a wash out. I breed T Carnifex and this year the number of duff ones is a lot less than 50% however I think half the time its the size of the container you keep the eggs in and the quality of the water, that stops fungus from affecting good eggs If you have it in your mind anyway that you are going to lose 50%of them maybe you don't try as hard as you should ie water quality and fungus inhibitor

Having losses up to 100% could not be blamed on the genetic defect. There must something different go wrong, like infertility or bad water management.
How is the success with other triturus species as alpestris?
This would be a good control group.

Uwe

 

[KennyDB]

Hi Uwe

I see the same in T.karelinii kaukasus eggs I'm raising. Half of them died in the egg.

 

[uwe]

Hi Kenny,

thanks for the input.

Uwe

 

[vincent]

Having losses up to 100% could not be blamed on the genetic defect. There must something different go wrong, like infertility or bad water management.
How is the success with other triturus species as alpestris?
This would be a good control group.

Uwe

Hi all if you read some literature it states the size of crested newts being up to 8 inch but says these are probably crosses if you look at the geographical locations of different species of the Crested newt they do probably inter breed and could be like the green frog complex ie Marsh frog x Pool frog = Edible frog. On another note my friends pond produced lots more Alpines, Smooth and Palmates than in previous years, last year ,but the mild weather we had in winter time several years previously may have affected fertility We seem to be losing the numbers of Crested newts in Britain that we used to have and no one seems to know why? My own theory is the population is managed wrong a zoo should have a large population of newts and should sell or give to people to stock their own ponds and run courses on habitat management for newts. WHY on earth are people given a licence for a wild creature to spawn in your pond.Then people may start an in depth study as to why 50% of the eggs die and what could rectify the situation However in Britain we seem to be getting thriving populations of Egrets ,Herons ect and then you get 4000 bird watchers on an area no bigger than a carpet tile, and these birds could devastate any amphibian populations but they cant compete with the birdy folk, less ranting hope your study proves useful :frog:

 

[uwe]

Could you please summarize what your staement has to do with the original question.

Uwe

 

[stavroske]

At this point I have 6 larvea of my T. cristatus and 7 died while developing. A 7th one is hatching at this time.
I have about 80 eggs so I'll let you know what the statics are ones they all hatched.

 

[uwe]

Hi Steven,

thanks for the first data. Sounds very close to 50/50.

Uwe

 

[vincent]

Could you please summarize what your staement has to do with the original question.

Uwe

Hi Uwe right breeding by any animal takes up a lot of resorse's of that animal to then have 50% of what you lay go rotten before you start seems outrageous. The trouble is we as animal keepers try to raise as many of our offspring as we can maybe we are raising them wrong. In the wild they may interbreed with other species of crested newts every so often to maintain a viable population,eg if you bred a Crested with the Marbled newt then crossed the offspring back with Crested or Marbled which ever they most resemble would that cure/ or ease the problem with egg viability in some literature it states Crested newts much larger than they are now and are possible hybrids we know Crested and Marbles interbreed as it has a name [CANT REMEMBER IT BUT IT STARTS WITH B] but is this natures own answer to sorting out the problem.

 

[eljorgo]

[CANT REMEMBER IT BUT IT STARTS WITH B]

Triturus blasii [cristatusxmarmoratus]

 

[uwe]

Hi Vincent,

interesting ideas, but with no practical impact.

First of all you mean Tr. blasii, which is an interbreed of marmoratus and cristatus. These animals are nor fertile any more.

Other interbreedings between cristatus and other Triturus as alpestris or vulgaris and so on are from the biological standpoint not possible (inter-species breeding). So your idea has no biological basis.

Your statement: "The trouble is we as animal keepers try to raise as many of our offspring as we can maybe we are raising them wrong."
I can´t see the point. We try to raise the best available amount of off-spring of healthy animals. This one of the main reasoning for this hobby. The breeders are not resonsible for this genetic defect and will - if the statement on defect is correct - only get the 50% of healthy off-spring.

To emphsize it again, reason for this thread is to check the literature statement.
And again a total loss of 100% eggs is not due to genetic reasons, but to not fertilized eggs or wrong raising conditions.

Best Regards

Uwe

 

[SludgeMunkey]

I have personally experienced the 50% die off with T.marmoratus, T.carnifex, T.karelinii, and T.dobrogicus. To be fully truthful though I did not have complete batches of eggs to work with. In fact in the samples I had all of the marms and dobros failed. All but one of the karelinii failed too. The carnifex showed a perfect 50/50 split.

 

[Azhael]

Uwe, may i ask why you still use the old clasification? You are free to do so, if so you choose, despite the change having been made a few years ago now, but i really think it´s causing a lot of unnecessary confussion. Neither Lissotriton nor Ichthyosaura have absolutely nothing to do with the cromosomal situation of the true Triturus.

The hybrids of the "cristatus" group, which doesn´t include T.marmoratus nor T.pygmaeus, are all fertile, yet that makes no difference, since they all carry the choromosome and therefore all resulting offspring, no matter the combination, will inherit it (as always, half of them will be heterozygous and survive, and half of them will be homozygous and die).