Premature Wetting ?

[stormhawk]

Hello everyone,

Recently on Saturday (17/04/04), I wetted a bag of eyed-up Simp. marginatus eggs that I bought from a friend in France. They were supposed to be wetted on 28 April 04 but I took the risk and wetted them 2 weeks in advance, using the Simp. constanciae incubation time and the colour of the embryos' irises as a guide.

The resulting number of fry was astounding with 8 hatching within 3 hours of wetting and about 24 more that appeared throughout the night, but the sight that greeted me was none-too-wonderful. A large number of them were under-developed and some of those which seemed to be larger than the others had their little pectoral fins moving but their tails were curled up in the embryonic position. Some had a red dot on where their hearts were supposed to be. The end result, almost 30 fry dead. Was this a result of premature wetting I'd appreciate any viewpoints or comments on this.

On the other hand, the good news is that, I managed to save 3 good eggs from the marginatus and have re-bagged them for a later wetting, this time following the date on the bag. My constanciae have given me a good number of eggs :wink: but the fulminantis have not been producing any good eggs yet. Found one egg but it was infertile.

[turaco]

Was discussing this issue with Jian Yang earlier & I too had similar problem on other SA species. In fact, I wet mine on time. How do we judge from the eyes if the egg is ready? I do see eyed-up, but how 'big' are the 'eyes' suppose to be as a sign of readiness aside from the given incubation period?

On the other hand, my 7-month incubation RAC eggs(that was a forgotten bag of eggs) hatched good & healthy fry without giving any problem .

[hwchoy]

whoa lau, your title very misleading

[stormhawk]

Gan, I observed several things that were different among the fry. The larger ones had grey pigmentation on their bodies, especially around the head area and they had larger heads in comparison to the others. Their pectorals were also fully formed and they did not have the red dot like the less developed fry had. I realised this when I was looking at the fry that hatched. The red dot could be their hearts whereby the mature fry would have a transparent heart that we cannot observe except by looking through a microscope.

I believe that by looking at the colour of the egg, we can somehow predict the viability of the fry. Clear eggs with fully formed eyes would not be a good indicator to wet. From my earlier observations on constanciae eggs, some eggs showed a darker colour than others. This could be a deciding factor as to whether its time to wet them. Only by using a torchlight can anyone see the true nature of the developed embryo.

[timebomb]

Jianyang, Turaco,

Did you remove the peat from the eggs when you wetted them? I'm not sure if the deformities you described are symptoms of premature wettings but separating the peat from the eggs is known to throw up more belly-sliders.

Loh K L

[stormhawk]

Choy, why'd u say it's misleading? Care to explain??

KL, I didn't separate the eggs from the peat. I wetted them as they were from the bag I got. The guy that I got the eggs from sent me a file attachment in which he says that using cold water (about 20degC) reduces the number of belly-sliders in conjunction with the use of 1/8 of an oxygen tablet. The coldwater method works for eggs from constanciae, marginatus and Austrolebias nigripinnis.

I think the time of day when we wet the eggs does affect the overall viability of the fry. The last time I wetted eggs from the constanciae, it was at night, when ambient temperature was much lower than it is in the day. The next morning, I had plenty of constanciae fry that were already free-swimming, and the thing is, I never used coldwater, just plain tap-water and no oxygen tabs then.

[hwchoy]

Choy, why'd u say it's misleading? Care to explain??

I'm sorry, I just have this nasty habit of reading everything as if they're from FHM magazine :wink: “premature wetting” eh?

[imported_lily]

Hello Jianyang

Did you remove the fry immediately after they are hatched? If you leave them in the peat moss and removed after 24 hours, chances of them surviving are much higher. For some strange reason, the peat moss seems to stabilize those weaker fry if they are kept longer there. This is what I have observed.

[stormhawk]

Lily, I didn't remove the hatched fry. I only remove fry that are free-swimming. If I see none are free-swimming then I leave them in the hatching tray. I did like what you said with the MAG fry that I got from the eggs that Gan passed me and none survived after I moved them to the new container. Move them too soon and all will die. I only took the free-swimming fry from the first batch of eggs that I got from the constanciae. All survived the move.

[RonWill]

Jian Yang, at least it wasn't an 'eye-popping' experience with the premature wetting!

I suspect that for eggs collected from the country of origin, it's best left to incubate as stated on the bag's label. Early dunking might work for eggs that you personally collect.

Correspondence with Wright seems to suggest that if 80% (or higher) of the eggs are eyed-up, it should be 'safe'. Then again, we're in different climates and YMMV.