Delicate dobros?

[jewett]

I received some dobro eggs the beginning of this past February. I had read through some threads on the forum about rearing these guys and learned that most hobbyists think of them as tough and easy. I decided to raise them like I have raised all my other larvae - simple small dishes with floating plants, frequent water changes, etc. I fed them micro worms, BBS, and water fleas that I harvested from a pond by my house.

I had 11 larvae develop and slip, and they seemed to do well. When they were about a month old I had 6 die off in 2 days. Their tails would develop a "kink" (some looked like they may have grown fuzz on the tails, too, but that may have been postmortem) and within hours of my seeing the tail kink they would be dead. I wondered if it was a water quality issue, as I was using BBS and dumping in large amounts, and the larvae weren't eating all the BBS. I changed the BBS- fouled water the next day, but wondered if it still may have been the cause of the deaths, because the deaths occurred within about 48hrs of a massive BBS feeding. After that I stopped using the BBS altogether (maybe the larvae had ingested BBS eggs, and all had intestinal obstructions that caused the deaths?), and just switched to the locally collected Daphnia and micro worms. No problems and I thought the issue was resolved.

Thursday night I did a routine water change, and Friday morning I awoke to more dead dobro larvae - all but 1 were deceased. I immediately removed the one remaining larva into a clean dish with 100% "new" water (aged water, though). This lone larva has continued to eat, but this morning it has the dreaded tail kink.

Has anyone experienced this before, or has any ideas as to what I did wrong? I am also currently raising 2 tanks of alpestris larvae (one tank of separated larvae, and one tank that is being raised with their parents) and have only seen this tail kink/death with the dobros. These other larvae are also being fed on the "wild" Daphnia, and they are doing very well. The dobro's were in small dishes, with frequent water changes, but maybe a water quality issue? I have to admit I do not check water quality but the water fleas would still be swimming around in these dobro dishes, and water fleas are good water quality indicators, right? Does it sound like I introduced something nasty in with the dobros, but by luck the same nasty did not get into the alpestris tanks? Though the dobros are the only larvae I have been raising this year via the small container method, I have raised many other larvae from multiple species this way before, and have never experienced this until now.

I would really like to try this species again, but I DO NOT want a repeat of kinked tail deaths. Maybe I should just skip the small contained and go right to a 10 gallon cycled tank? Please, all you experienced raisers of dobrogicus - help me!

 

[EasternNewtLove]

Re: Delicate dobro's?

I know just how you feel. I've had several larva die from this kinked tail thing. I'd love to know what's causing it. I just had 9 larvae die today. I had added some microorganisms from a puddle near a pond to feed them... I'm really upset about it. These are notophtalmus viridescens larvae though.

 

[Azhael]

Re: Delicate dobro's?

It´s difficult to tell what the origin of the problem might be as there could be a number of causes, but based on my limited experience i´d suspect water quality issues. I have seen kinked tails in dobrogicus in 3 or 4 occasions and it always happened with small larvae that had just developed the back legs. At that point i had been housing them in small containers to avoid agression and water quality wasn´t the greatest. With one exception i´ve never had any deaths or kinked individuals after moving the larvae to larger, much more stable containers.
I find that the small container with frequent large water changes method doesn´t work for me. The young larvae seem to be somewhat delicate, although after they have developed their back legs and acquired a certain size, they are extremely easy to raise, they really are.
I´m sorry this attempt didn´t succeed. If you try again (i recommend it, this is a fantastic species!), i´d suggest the 10 gallons, or perhaps individual medium sized containers with few water changes at all (this may be necessary because they are blood thirsty cannibals).

 

[Otterwoman]

Re: Delicate dobro's?

I haven't noticed the kinked tail in my larvae.
I use the "dirty tank" method of raising them, maybe I don't see them because of that.
Also, the last few years, all I feed my larvae are blackworms- minced very tiny, and slowly increasing in size until I switch to minced nightcrawlers. I have found them easy to raise.

 

[otolith]

Re: Delicate dobro's?

Sorry to hear about the bad luck with the dobros. I raise them up in 2 gallon containers, about a dozen larvae in each. I do partial daily water changes and feed wild daphnia. I havn't seen any develop the tail kink and fuzz you mentioned but they are pretty water quality sensitive until they develop their back legs. I still have some eggs if you'd like me to send another batch your way.

 

[jewett]

Re: Delicate dobro's?

Thanks for all the input. I will try them in a 10 gallon, and really hope this time goes better.

Perry, thanks and I'll send you a PM.


Heather

 

[caleb]

Re: Delicate dobro's?

I find that the small container with frequent large water changes method doesn´t work for me.

No, me neither. I get best results for all European newts when I do zero water changes from hatch to back leg growth. It does look a bit silly with a few eggs in a large container, and it does look very messy by the time they're ready to be moved... but there are fewer deaths.

If I do have to move larvae in an emergency, I try not to use nets, but to move them in water, either by scooping them up in small container, or VERY gentle use of a baster. Not sure if this really makes a difference, but I feel it's less likely to damage the gills, limbs and tail.

 

[jewett]

Re: Delicate dobro's?

Caleb, it's interesting you make the comment about avoiding using nets with them. I almost always use a turkey baster, but Thursday night (the night prior to the 2nd round of die offs) I used a brine shrimp net to transfer them to the clean water dish. I do wonder if nets could be a factor, though I will not test that method - turkey basters for every transfer, every time from now on! And less transfers overall, I am sticking to large container, few water changes. I hope round 2 is more successful...

 

[Jennewt]

Re: Delicate dobro's?

Kinked tails was something I observed the one time I had a mass die-off of T. karelinii larvae. It's described in the case history at the bottom of this article:
Caudata Culture Articles - Why Larvae Die

I agree with the others who recommend using a "dirty" established tank. It's a bit unnerving to put delicate eggs/larvae in a messy tank where it's hard to even see them, but I've never had a die-off with that type of rearing.

 

[Niels D]

Re: Delicate dobro's?

I'm raising them in water from a puddle, because I've also got bad results feeding them BBS in small setups. This water contains a lot of wild daphnia, cyclops and other little food items. The dirty water method also works very well for me btw.

 

[Neotenic_Jaymes]

Re: Delicate dobro's?

No, me neither. I get best results for all European newts when I do zero water changes from hatch to back leg growth. It does look a bit silly with a few eggs in a large container, and it does look very messy by the time they're ready to be moved... but there are fewer deaths.

I use the same method in raising larvae also. I usaully don't do a water change until the back legs come in. It's always worked for me. I've tried the "every day water change" method and it didn't go so well.

 

[jewett]

Jen, I just read that article last night in my continued research in the hopes I can prevent this sort of thing from occurring in the future. I wonder if once the tail is kinked if there is really no hope of saving them...

I am definitely using the "dirty tank" method in a 10 gallon, and tomorrow I will be filling it with water from some of my adult tanks. I am also going to start some Daphnia in there. I should be getting the replacement eggs in about 2 weeks from Perry (Otolith). Thanks Perry!

I have raised several dozen Asian newt larvae in the small container/frequent water changes way, but I find it interesting that European species do not do well with this method. I think I raised my original group of Ichthosaura alpestris this way several years ago, but in hindsight the containers were much larger than what I had the dobro's in. All in all, I think I am done with it - it's just not worth the risk to me. And less work with better outcomes is always preferred!

Thanks for all the advice and comments - this site is such a great resource because of all of you!

Heather

 

[Master B]

Greetings And Salutations Fellow Forum Compatriots,

First and foremost, I am deeply saddened by your misfortunes. From my perspective, it sounds as though you have introduced parasites from your local pond. Many broods of both caudates and other vertebra, such as fish, are lost by adding water from a local pond or other wild body of water.

I had received some T. dobrogicus larvae in the pellagic stage this February as well (from a fellow forum member), and raised them successfully without a single instance of mortality. I raised them for their initial month on a diet of frozen daphnia and self-cultured white worms (which were chopped). Again, I did not experience the dreaded tail-kink syndrome or any other malicious ailment. I feel as though I was so successful in substantive portion to utilizing sterile foods, combined with bottled and 10 stage filtered water changes every 48 hours. I find this species to be quite hardy and outgoing.

Farewell,