WHAT DOES FERTILE CHICKEN EGGS FOR SALE NEARBY MEAN?

They lay a large speckled egg. The eggs, like all eggs, are white and the second to last functionality is to put down colour on the egg, prior to the bloom, which safeguards the egg from micro organism and keeps the humidity in so it does not dehydrate, however is porous plenty of Hence the chicks can breathe. It is absolutely quite amazing!  Or