Egg culture techniques

[cuttlegirl]

Since there are a number of members with soon to hatch eggs, I thought we could start a thread for some ideas on how to raise some of the embryos.

I don't know where my brain has been lately . But, I have been thinking of this problem of culturing babies.

A long time ago, I used to culture marine invertebrate embryos. In the lab, we had a water table (literally a table with edges and shallow flowing water). You could place petri dishes and culture dishes in the water table and keep the temperature stable. We would place the embryos in several petri dishes and then you could have several groups of embryos to use for experiments.

We used pipettes (or eye droppers) to transfer the young. I used to turn an eye dropper backwards (take the bulb off and put it on the narrow end) to suction the embryos to transfer them. This is useful if the water in the petri dish becomes contaminated, you just move the little one to a new dish with clean water.

By using the petri dishes, there was enough surface area for the water to become oxygenated and the water table kept the temperature constant.

So, some key points for raising embryos are constant temperature, and oxygen exchange. You do not need water movement, which can damage the young, you just need a large surface area for oxygen exchange.

As far as food requirements, it will depend on the species of octopus.

I found this link which may give you some ideas to try. http://www.garf.org/news3p2.html

I am sure I have forgotten some key points, but at least this gives you a place to start.

 

[monty]

This prompted me to make a sub-forum for the topic, and I've moved this thread there... let me know if it doesn't work; this is the first forum I've created...

I'll stick this thread, but we may also want to have a "so, your octo laid eggs" thread or similar for the not-infrequent people we get who are starting from zero (OMG my octopus has eggs WHAT DO I DO HELP!!1!1!?!?)

Any volunteers for writing a gentle introduction thread?

 

[cuttlegirl]

It would be nice to separate this into small-egged species and large-egged species. Also a list of the small-egged and large-egged species. I would attempt a list, but I don't have much spare time...

 

[monty]

It would be nice to separate this into small-egged species and large-egged species. Also a list of the small-egged and large-egged species. I would attempt a list, but I don't have much spare time...

I considered that, but it seemed like splitting hairs a bit... I decided to go with just one subforum in octopus care so that people who don't know much wouldn't be too confused. Still, I'm happy to change positions. I also considered whether it was wise to leave out cuttles, but there seems to be less problem discussing cuttle eggs in the regular cuttle care department...

 

[Cryp_Sis]

My O. bimaculoides (wild-caught by a collector about 6 weeks ago) has just laid eggs. Is it possible that she has held onto sperm for this long, and that they might be fertilized?
If so I would like to try my hand at culturing the eggs, but would it best to leave them in the den for now, or remove them ASAP to a separate container? I would be worried about losing hatchlings in the system.
I read with interest a previous post about sacrificing an egg under the scope to look for an embryo, but I assume that I would need to wait a while before I try that. Also, I will continue to search for information, but any input on roughly how long the embryonic stage lasts before hatching would be most appreciated. Or if anyone can point me towards any information at all about culturing O. bimaculoides that would be a big help.
Thanks in advance,
Lene.

 

[cephaloholic]

bimacs are large egg species so i think they will be ok to feed in individual net breeders. ive heard of someone putting the hatchling in empty water bottles with some live rock.

 

[monty]

It's quite likely the eggs are fertile, for a wild-caught animal. Have you seen the eggs yet? Sometimes species ID is difficult between the large and small egged bimac species (bimaculoides and bimaculatus). If it's a large-egged octo, you stand a good chance of being able to raise some of the young, if it's the small-egged one, it will be nearly impossible. You might want to start a new thread for your experiences, I'm hoping that in this forum we'll have one thread per brooding octopus.

A good reference for raising bimaculoides is Zyan Silver's article in the "lots of cephs" issue of TFH from around 2 years ago. I expect Nancy and Colin's book will be good as well, but we haven't seen it yet...

 

[Cryp_Sis]

I got a brief look at the eggs (she is keeping them well hidden between her and the den wall). I am afraid I have already stresssed her out quite a lot by gently picking up the den this morning to see if she is still alive, so I am loathe to investigate further. All I could tell is that they are white, and about 6-8mm long, at a guess. I did not see many (two or three) but have no idea how many more she may have in there). Forgive my ignorance, but does this sound like large- or small- eggs?
I am on the fence about leaving the eggs where they are for now, versus removing them to culture dishes. Is there danger of the mother eating the eggs, or do you think they are better off where they are for the time being?
Thanks so much,
Lene
P.S. The brooding mother just took a crab that I presented to her (she did not leave her den, just reached out with one arm). Am I being overly optimistic taking this for a good sign, or is it a given that she will die soon?

 

[Animal Mother]

Sounds like, from your guestimate, that they are large eggs. Small ones hatch out at about 2mm.

 

[DWhatley]

Jennifer,
Thanks for the experienced suggestions and I am glad our plights have you thinking since you don't have any cephs (I was going to say little ones but that would be wrong ) at the moment.. I sill have a couple of weeks so I am trying to dream up a DIY water table to add to my current thoughts. The one thing that concerns me about the petri dish is that these are pelagic and not benthic and I wonder if they will eat.

Monty, thanks for starting the subforum. I will try to go through and find some of the links where others have tried dealing with the small eggs and put the references in one post.

 

[cuttlegirl]

Is there danger of the mother eating the eggs, or do you think they are better off where they are for the time being?

I would leave mom and her den alone. She will do a much better job of caring for the eggs than a human. Once they hatch, you can remove them to a smaller container.

 

[cuttlegirl]

The one thing that concerns me about the petri dish is that these are pelagic and not benthic and I wonder if they will eat.

You are just trying to create a small environment where you can feed them. If it looks like the petri dish is too small for them to move around comfortably, you could try a larger container, just make sure it has a large surface area to volume ratio.

 

[monty]

Monty, thanks for starting the subforum. I will try to go through and find some of the links where others have tried dealing with the small eggs and put the references in one post.

Awesome! Thanks!

 

[butler]

Thanks for the information. I recently had an octopus which hatched hundreds of tiny babies. Majority sucked into filter before I ran out and bought a 10 gal tank, heater and airstone. I put some live rock and tank water in there and once the water temp was equal, tranferred as many remaining babies as I could with a cup. They died rather quickly in that environment as well. Soon had dead mother with no babies. Thinking of trying again but wanted to ask if this advice applies mostly to "large egg" varieties or "small egg" varieties. I read somewhere that small egg hatchlings are nearly impossible to raise... true?

 

[CaptFish]

to TONMO

I read somewhere that small egg hatchlings are nearly impossible to raise... true?

True. It has been done by a few biologists in a Lab but never at home. Even with the Large egg species it is VERY difficult and survival rate is low. D can chime in a tell you more as she just did it successfully with. O.briareus a large egg Caribbean species.