Very true, if it were bacteria it would be very strange that it showed up in only one breed, and showed up in every single shell, but did not show up in any shell of the other breed. I think I will take an egg shell to my vet and have him take a peak. I'm inclined to say it's not bacteria given these findings, but a vet would be able to say for sure upon seeing a shell, I think.
Exactly, Pyxis... and that's why I did check every single one... and you are correct, every AC had them but not a single Araucana did...
Again, I will stress and keep repeating, I don't give credit for it proving a claim that an AC is 'PURE' but a curiosity that may be connected to the fibromelanism...
My next thing to see, once my girls start laying, is to compare the more spotted shells with the amount of fibro expressed in the chicks that hatch from them... would be curious to see if there's an correlation in more spots and deeper fibro...
And I would be very interested in what your vet can figure out... please keep us posted...