Why such variance

[CynthiaM]

So, does anyone really know how long chicken eggs can be held before incubation to be viable. I have read so many different things like maximum of 7, 10 and somewhere I read 14 days. Anyone know for POSITIVE how long? Elaborate please.

 

[Paganbird]

Here's your answer:

Storage time—Ideally, eggs should be set in the incubator as soon after gathering as possible to maintain egg quality. If eggs are to be stored before incubation, the best hatchability occurs when eggs are stored for less than 7 days from the time they were laid. However, some species are more sensitive to storage than other species. Hatchability decreases rapidly in eggs held in storage for
more than 10 days. Storing eggs longer than 2 weeks also can extend the normal incubation time as much as 1 day.
Temperature and humidity during storage—Fertile eggs should be stored at a dry bulb, normal temperature between 55 degrees F and 65 degrees F, or 13 degrees C and 18 degrees C. Embryos will begin to develop abnormally, weaken and die if the temperature is too high. A low temperature also causes high embryo mortality. Storage temperature should never exceed 72 degrees F (22 degrees C) and never go below 46 degrees F (8 degrees C). Egg storage at room temperature or at normal refrigerator temperatures (32 degrees F to 40 degrees F) is not acceptable because hatchability decreases.

Here is where I got my info: http://gallus.tamu.edu/Extension%20publications/b6092.pdf
You should print the guide out so you have a copy. It answers a lot of basic hatching questions.
Good luck with your hatch.​

 

[hinkjc]

That is an excellent guide and one of my favorites when I first started incubating. I will note that wild turkeys establish and place eggs in a nest for up to 2 weeks before sitting to incubate them. Careful thought about temp/humidity is not considered and they hatch clutches successfully. Just something to consider. I'm not saying the guide is wrong, as I do believe it helps us achieve more successful hatches, however wild birds have been doing this naturally for much longer than any of us.

 

[rebelcowboysnb]

I saw a study a few years back where they graphed the hatch rates of eggs by how long they were stored. They did some in the fridge an some at room temp. The eggs at room temp gradually dropped from 98% to 75% days 1 threw 14. Then it dropped to 30% by day 16. After another week it was close to 0. The fridge eggs on the other hand dropped to about 70% by day 3 an leveled off. I dont remember how long the study was but the fridge eggs kept hatching for a long time. What they concluded was that putting eggs in the fridge hurt hatch rates for eggs under 14 days but the line crossed after that. Egg that have to be stored over 14 days do better in the fridge. But it also showed that for most people eggs should be stored out of the fridge an for a max of 14 days. But if 75% hatches are to low for you then you may want to cut that in half. I wish I could find that study again. I collect for a week at a time. Thats what works for me.

 

[riftnreef]

Pagan....pretty nice little booklet...thanks for the link!

 

[Akane]

The difference probably comes from the fact that an egg doesn't just suddenly quit at a certain day so how long you can store an egg for becomes a loaded question that depends on your goals. If you store a bunch of eggs for 2 weeks you will probably still get chicks. It's very unlikely you will get as many chicks as if you set them by 1 week but they aren't all bad on a specific day. You also might increase hatch rate a little if you set them after 2 days instead of 7 days. If you want to go for the maximum hatch rate then you want to set them as soon as possible. If you don't care if a few don't hatch then you can store them longer. If you are collecting from your own chickens and not doing hatches back to back then you might as well collect eggs for a little longer. If you get 4 eggs a day and you collect for 7 days you have 28 eggs that are no more than 7 days old. If you collect for 2 weeks you still have 28 eggs that are no more than 7 days old but now you have another 28 eggs that are up to 14 days old. You will hatch more chicks with 56 eggs than 28 but since some are older you'll have a lower hatch percentage. If you are running your incubators constantly or selling chicks for profit then it's worth it to set only fresh eggs to maximize your hatch. If you are selling eggs then it's best to send only the freshest eggs and I'd prefer they weren't more than 4-5days old when shipped unless I'm not paying much. If you are just adding to your flock with a hatch or 2 a year then you might as well collect for as long as possible and just candle to remove any duds before they go bad.