Do Eggs start to smell while incubating?

[jtotherow]

As I went to turn them I noticed an odor. Does this mean they are dead or is this normal?

 

[HatchCraft]

A strong odor is a sign that one or more eggs are rotten. You need to identify remove the rotten ones before they rupture.

 

[jtotherow]

Thanks that is what I feared. Lost one but the other six do not have that odor and i see what looks like a embryo in them. Hopefully I will not lose anymore. We will be buying if so. But my husband now is saying what is the use of the rooster. Really! Thanks for answering me!