Rotton egg question


In the Brooder
8 Years
Apr 17, 2011
Christchurch, New Zealand
I was just candleing my eggs and they are at day 8. I had a egg that was all black so after thinking about it i decided to break open and see and yes it was a rotten egg. But i thought rotten eggs were meant to be clear? is that only at the start? Also some of the eggs i can see the babies etc but some look not clear but close to it it looks like it has a circle of i am guessing yolk moving around does that mean it was infertaile?

Thanks all for your help
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Hi there, im interested to here what people say about this! i was just about to ask the same question. I have 12 in the incubater on day 7 and the ones ive candled have just got a round darker Circle so im thinking there not firtile. I paid a lot of money for these eggs and if there not fertile i wounder if i should contact the supplier here in the UK...First time ive hatched so a learning curve for me lol..Tracy.xx
The language people use when talking about eggs can be confusing.

If someone candles and says their egg is 'clear' that usually means an egg that never started to develop. This could be an egg that was never fertilised in the first place, or an egg that was fertilised, but got bumped about during shipping to the extent that it got 'scrambled' which is a word used to describe eggs that have had a very rough time during shipping. You can't really tell the difference between the two, which is why people should be wary of contacting sellers and complaining they've been sent infertile eggs!

A clear egg is different from a rotten egg. A clear egg could sit in your incubator for the whole 21 days of incubation, and if you cracked it open after that you'd most likely just find a warm eggy smelling mush of mixed up egg white and runny yolk. I usually remove clear eggs at 12-14 days and feed them to my dogs, as they're still fine to eat. They're not bad, they're just non-developers.

A rotten egg is one that's become contaminated by bacteria, which will grow and multiply in the warm incubator conditions. A rotten egg can develop from either a clear egg OR from an egg that was fertile and had started to grow an embryo but then died. A rotten egg will stink to high heaven, even through the unbroken shell, and I don't think that even my disgusting greedy horrible poo-eating dogs would ever be stupid enough to try eating one. Though I wouldn't be confident enough to put money on it!

Sometimes confusion is caused when people say they've got dud eggs or bad eggs, meaning they're annoyed about having non-developers, and other people assume that by 'bad egg' they mean a rotten one, not just one that wasn't any good...

It's hard to describe what eggs should look like when candling, but if you're not sure what you're seeing, best to leave them in! A clear egg isn't perfectly clear and yes, you'll probably be able to see the yolk kind of moving about slowly in there. If at about 7 days you can quite clearly see a little black dot (the embryo) and a network of veins in some eggs but not in others, it's most likely that those others are non-developers.
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I clicked on the 2 links in reply# 3 but got a *can't open link* message
By day 8 you should see veining. Shine you light on the big end of the egg and look around the aircell for spider like veins. You should also by now see a dot with alot of the veins running to it. If it is all dark I would say its probably rotten, but sometimes the darker and blue and green eggs are harder to see in. I use a Coleman Maxx flashlight to candle. Its 90 Lumens and can shine through most eggs.
I am just chiming in to say make sure you candle in a 'darker' room and have a powerful flashlight! I hatched for the first time this last spring and bought about 7 flashlights. Finally I ordered one online that was small but had a rubber-y tip shaped to go over the end of the egg. THAT helped me more than anything in my candling attempts. Days 8-10 you can SEE the veins. Something else I noticed was that the blue eggs I could really see the veins.

By the time I was setting my second incubator full I could go in and simply put the little flashlight on the top of the egg, through the little window that I removed for candling, and I could quickly check the eggs and put the window back in!!! That hatch was 100% and probably because I was not having to make multiple trips back and forth to my closet!

Oh, my, am thinking it is time to get the incubator out and dust it off and get ready for another hatch. What was it my DH said before leaving to work out of state???? NO MORE CHICKENS. Ah, heck, he really did not mean it!!!
love the last comment about your husband - he sounds just like mine. me problem is mine comes home each night and sees another broody box and goes "not another one" :)

I candled one today and it was a blue egg. I have done blue eggs before with this tourch with no problems - anyway it was black as black so i cracked it open as the last black as black ones i have had which i can not see any veins were rotten i thought ild pull this one out and see well when i cracked it open it smelt rotten but it still had a yolk and veins but not the normal amount of veins or baby you would see for a 12 day old egg. So question is do the rotten ones go fully black when your candleing before the inside is full off?
I will say again i have a great tourch now and i have candled blue eggs before with this tourch with no problems.

Thanks for your help
When cracking rotten eggs you should put them into a ziplock bag and then break them. You can still see what's inside but there won't be that horrible smell to deal with

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