Egg laying in liquid medium?

Hello everyone.
We recently tried to culture worms (wild-type N2) in liquid medium, but the worms doesn’t really lay egg.
We are quite new with liquid medium, so not so sure about this condition.
I read this chapter in WormBook, and it is stated that the worms tend to hold their eggs.
Is egg-laying delayed when the worms are in liquid medium?
Hope to get more input on this condition, thank you :slight_smile:

Hi YuuYee,

They retain most of the eggs in the liquid culture and eventually eggs hatch inside and the mothers become bag of worms. If you want to grow a lot of worms in liquid culture, I suggest you first grow them on several plates until mothers become gravid, then bleach the mothers and purify the eggs and plate those eggs into the liquid culture.



Thank you for the input, I have some idea now :slight_smile:
May I know why this phenomenon happens?
Why the worms tend to retain their eggs in liquid culture?
I tried to search for literature, but can’t find the reasons.
Thanks :slight_smile:

You’re welcome. I have no idea why it’s happening. Perhaps contact with a solid surface induces egg laying?

I believe that worms grown in liquid culture are relatively stressed, i.e., they express stress related proteins.
This may be related to the retention of eggs.

Thank you for the input.
May I ask, do you have any idea on which stress related proteins being expressed?
Just to elaborate further on my case, we bleach the gravid worms and plate the eggs obtained into liquid medium.
While the worms growing (worm hatching to adulthood), we need to provide our treatment and assess the egg-laying afterwards.
If the worms are stressed or having some other reasons for unable to lay eggs, can we do anything to improve the condition, or if so, the worms will continue to retent?
Thank you :slight_smile:

I am far from an expert on this subject. But a brief web search found the this worm breeder’s gazette article:
You might wish to contact Jason Lieb for more information,

What are your liquid culture conditions? Some conditions are more stressful than others. If they are in a flask or tube that is being shaken then this is like the kiss of death for being a stressed worm.

It is possible to grow the worms in a liquid culture where they are relatively happy but it only works in small batches, but that is not useful if you are just trying to amass a large quantity.

Depending on the volume, you could get pharmacological. Throw in some Serotonin, Levamisole/tetramisole or even imipramine (acts through serotonin). All will strongly stimulate wild-type animals to lay eggs.

Use whichever is cheapest (probably tetramisole). I would filter sterilize the drug stock. And I’d have to find concentrations but they are out there in old studies of egg-laying. Try David Weinshenker’s stuff from the Thomas lab:

And consider pelleting your worms, washing in M9, and resuspending in M9 + drug to keep the volume down. I bet this will give you very efficient egg laying.

Thank you for all the suggestions given :slight_smile:

We grow them in liquid medium at room temperature (around 23C to 25C). Maybe they are stressed, the amount of worm is also lesser compared to those grown on NGM.