Why are eggs in the fridge developing spots after a few days?

[Tanner88]

After being in the fridge for a few days, my normal looking eggs start to get what looks like oily spots all over them. I think these eggs are coming from a buff orpington. My barred rock eggs don't seem to spot as much. Is this something that I should be concerned with? Are the safe to eat? The egg on the left is what they start out like, the right is what they turn into.



Thanks for the help!

 

[Kelsie2290]

Interesting, sounds like what they mention below, especially since they say it is noticeable or develops a day later.
http://edis.ifas.ufl.edu/ps020
"Mottled shells have pale translucent spots (sometimes called "windows") of various sizes. Such eggs appear normal when laid. The mottling develops later and may be noticeable half an hour after laying, although it is more easily detected a day later. This abnormality is inherited, although a similar effect can be induced artificially, such as when a wet, newly laid egg slides across the wire cage floor instead of rolling, or when a hen's toenail scratches the surface of a recently laid egg."

http://www.intervet.co.th/binaries/50_Egg_Shell_Mottling_and_Hatchability_tcm62-17670.pdf

 

[Happy Chooks]

Here is some more information. Looks like a porous shell.


http://www.thepoultrysite.com/publications/1/egg-quality-handbook/23/mottled-or-glassy-shells

 

[Tanner88]

So from what I am reading this is something that is in the bird's genes? Still not sure about what all this means. Should I treat them differently than normal eggs? Is bacteria getting into them? The shells seem to be a lot thicker than what you get from the grocery store.

 

[Kelsie2290]

If the egg shells are of a normal thickness, don't think I would worry about it for personal use. From the hatching study, it doesn't seem to make much difference, the mottled eggs actually seemed to hatch better than the regular eggs, go figure.