Storing silkworm eggs ?

Greenhorn

New Member
I know you can keep silkworm eggs in a refrigerator, but for how long and at what temps can the survive in ?
 
I have successfully hatched eggs that have been in the refrigerator for up to 5 months. I never monitored the temps, but if I had to guess I'd say they were between 3-5 degrees celsius. Freezing will kill the eggs.

I have currently pulled out a batch that have been in the fridge for about 9 months, but it doesn't look like they're going to hatch.
 
Dark grey is good. When they are light coloured (like an off-white) they are infertile.

According to this site: http://www.suekayton.com/Silkworms/eggs.htm, they can remain viable for up to 5 years! Well, I'll have to see how my 9-month batch goes.

It can take a while for them to hatch after you take them out the fridge. One batch hatched in 3 days, but the next batch took almost 2 weeks. Presumably it has to do with how long the eggs were out of the fridge before you put them in (I waited until all the moths were finished laying, so some had been out longer than others).
 
The eggs i have taken out are dark grey and are indented are they any good?

look with a hand lens/magnifier. If they are slightly indented in the middle this is natural - picture the little larva in a curl inside the eggs. If the whole egg is collapsed then they are ng. Storing them in the crisper section inside a small storage container (zip-loc/glad-ware type) with a piece of paper towel and a single drop of water on it is best. if you store them elsewhere in the fridge they have more of a chance to desiccate and are also subjected to more fluctuation in temperature.

I place mine on top of the UVB strip light in order to get them to hatch. ;)
 
Can female silkmoths mate and lay eggs more than once?

No. They die soon after laying about 150+ eggs. However a male is capable of mating more than once though he might be shooting blanks next time around. To give you an idea of the strength of pheromones (the chemical given off by the female that attracts the male - he "smells" it with his antennae. It is termed scenting or calling) I had a pair mating and a new female emerged nearby. The mating male broke away from his girl and moved on over to mate with the fresh female!! I have been rearing wild Lepidoptera for years and have seen many males after one female at once but never had a male actually break away! :eek:

If you watch, you may also see a male going around in circles when there is no female out. Sometimes a moth gets trapped in her cocoon which calls for surgery, but if you are not aware she will live call, lay eggs and die all in her cocoon. The male will detect the pheromone but will not be able to find it b/c she is trapped inside. So if you every see a crazy male (hmm...aren't all males crazy??:D) you probably have a trapped female.

lele - the one who never tires of watching Leps. ;)
 
will they mate right away or later? do you have to house them a certain way for them to mate? can you use the eggs right away?
 
the second a female is out the male(s) will be on her. She won't even have time to dry her wings!:eek: Don't worry, he will find his way to her no matter how you have them! Personally, I find it is easier for them to have something to grasp on to so I usually have them on a piece of plastic canvas, paper towel or brown paper bag. The latter is easier because you don't have to be there when they separate and she can lay right on it. Then you can cut around the eggs she has laid, wait a few days for them to turn gray (indicating they are fertile; if the remain cream color they are not) and then place them in the fridge. Sometimes they will hatch without a period in diapause (cool period) but it is usually a safer bet to give them one. See the other thread on this which gives some additional info, too.
 
I have successfully hatched eggs that have been in the refrigerator for up to 5 months. I never monitored the temps, but if I had to guess I'd say they were between 3-5 degrees celsius. Freezing will kill the eggs.

I have currently pulled out a batch that have been in the fridge for about 9 months, but it doesn't look like they're going to hatch.

What do you store them in and is there attention paid to keeping up humidity? I had a thousand developing (dark grey) eggs in a paper bag -glued to it's sides- in the vegetable crisper drawer. I believe it may have dried them out since none ever hatched.
 
If you can, you should let the male rest for a few hours in between mating.

Technically, the male's first mating only requires one hr to do.

Then you can physically detach the male and put him in a separate, and cooler room to rest. Shouldnt let him be in the same room with the females as the hormone drive him crazy, fluttering his wings and wasting his energy.

It is not good for either of them to mate for hours at a time. Boys work really hard at it. :D sometimes too hard and effort is wasted. They can be interlocked for days and that would actually lower the eggs laid.

As soon as they are separated, the female usually go straight to work as well.


After the male is rested for a few hours he can be put to another female. Let him mate a little longer this time, say 2 to 4 hrs.

Then separate and rest.

Next day put him to another female and mate longer than the 2nd one.

No more than 3 females should he mate with.

A skilled person in egg factory can produce more eggs than a novice, from the same exact moths.


I am working with zebras right now.. and I have to say I am disappointed with the number of eggs they lay. i am more used to working with the Chinese whites that lay over 400 each moth.

150-200 in zebras and counting the amt of work put into, I think it is worthwhile to buy eggs!


If you are working with sex limited zebras, naturally you'd have more gals then boys.. so, this is the method you should use.

How do you separate them? By holding on to the male only and turn right and left and right and left.. after a few turns they will drop off unharmed.
 
No. They die soon after laying about 150+ eggs. However a male is capable of mating more than once though he might be shooting blanks next time around. To give you an idea of the strength of pheromones (the chemical given off by the female that attracts the male - he "smells" it with his antennae. It is termed scenting or calling) I had a pair mating and a new female emerged nearby. The mating male broke away from his girl and moved on over to mate with the fresh female!! I have been rearing wild Lepidoptera for years and have seen many males after one female at once but never had a male actually break away! :eek:

I'm actually experiencing the opposite. My female silkmoth, Patapouf, emerged on Feb 16th so last Sunday. She mated that same day and laid her eggs late in the evening. On Tuesday, a newly hatched male mated her. She laid a second yet smaller batch of eggs. Thursday I had her on my hand and she began laying eggs again but only a few. Today is her eighth day as a Silkmoth. Everyone keeps saying they lay their eggs and die shortly after but I'm relieved that this does not seem to be the case with her.

Another pairing where the female mated, began laying eggs and then was interrupted and mated again by the same male also occurred.

So it seems sometimes there are unusual exceptions. I also believe that one male killed another as I found one with a wound on his abdomen and fluid mixed with hairs left near him. He was trying to interrupt a mating.
 
I realize this is a pretty old thread, but I've got a question! So I left some of the cocoons in a box on some paper with a few mating moths, and when I went to check on them the next day one of the females had laid eggs all over some of the unhatched cocoons (admittedly probably poor planning on my part, but I'm a first time raiser, and I'm not entirely sure how to separate the unhatched cocoons so that the newly hatched moths don't mate on them). Is there a way I can remove the eggs from the cocoons, and can the moth inside still get out? Also, is it possible to move the eggs one by one? Somehow one of the females ended up laying a bunch up the walls of the box instead of on the paper.
 
I realize this is a pretty old thread, but I've got a question! So I left some of the cocoons in a box on some paper with a few mating moths, and when I went to check on them the next day one of the females had laid eggs all over some of the unhatched cocoons (admittedly probably poor planning on my part, but I'm a first time raiser, and I'm not entirely sure how to separate the unhatched cocoons so that the newly hatched moths don't mate on them). Is there a way I can remove the eggs from the cocoons, and can the moth inside still get out? Also, is it possible to move the eggs one by one? Somehow one of the females ended up laying a bunch up the walls of the box instead of on the paper.
This is quite an old thread. It has some good info though.
I’m nowhere near an expert on silkies, but when mine laid eggs on a cocoon, I very carefully clipped off the threads beneath to release them. It was an already hatched one though.
Once my cocoons start hatching, I check them constantly throughout the day. Those that have paired I cover with a small paper dixie cup (few small holes poked in top) so not only can they be undisturbed, but the female will lay her eggs in a confined area. I also remove hatched cocoons if able. I just cut around whatever they’ve laid their eggs on rather than try to remove and risk damaging them.
 
This is quite an old thread. It has some good info though.
I’m nowhere near an expert on silkies, but when mine laid eggs on a cocoon, I very carefully clipped off the threads beneath to release them. It was an already hatched one though.
Once my cocoons start hatching, I check them constantly throughout the day. Those that have paired I cover with a small paper dixie cup (few small holes poked in top) so not only can they be undisturbed, but the female will lay her eggs in a confined area. I also remove hatched cocoons if able. I just cut around whatever they’ve laid their eggs on rather than try to remove and risk damaging them.
Thanks, that's very helpful!
 
Dark grey is good. When they are light coloured (like an off-white) they are infertile.

According to this site: http://www.suekayton.com/Silkworms/eggs.htm, they can remain viable for up to 5 years! Well, I'll have to see how my 9-month batch goes.

It can take a while for them to hatch after you take them out the fridge. One batch hatched in 3 days, but the next batch took almost 2 weeks. Presumably it has to do with how long the eggs were out of the fridge before you put them in (I waited until all the moths were finished laying, so some had been out longer than others).

So I placed my eggs in the fridge 2 days after they were layed. They just started changing colour. Ive posted a few batches of eggs out to people but they say they aren't hatching. Are all the eggs compromised because I didnt wait till they were dark grey / black before putting them in the fridge?
 
This is quite an old thread. It has some good info though.
I’m nowhere near an expert on silkies, but when mine laid eggs on a cocoon, I very carefully clipped off the threads beneath to release them. It was an already hatched one though.
Once my cocoons start hatching, I check them constantly throughout the day. Those that have paired I cover with a small paper dixie cup (few small holes poked in top) so not only can they be undisturbed, but the female will lay her eggs in a confined area. I also remove hatched cocoons if able. I just cut around whatever they’ve laid their eggs on rather than try to remove and risk damaging them.
I use toilet paper rolls cut in half to contain the mating pair and keep eggs in one spot.
 
So I placed my eggs in the fridge 2 days after they were layed. They just started changing colour. Ive posted a few batches of eggs out to people but they say they aren't hatching. Are all the eggs compromised because I didnt wait till they were dark grey / black before putting them in the fridge?

I think that is the case. I always wait until they turn dark. It takes around three days, give or take. Mine usually turn light brown and then black. Once they have turned dark, they are in diapause.
I've had several occasions where they didn't go into diapause. In this instance, they do not turn dark in a few days. Instead, they will have a seemingly brighter yellow center as the days pass, the slightly darker ring around it is the body of the worm developing. After that, a dark spot which is the head, will be visible, and is usually close to the side of the egg. Putting these in the fridge will not induce diapause.
 
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