ring around middle of half developed egg

[dstinett]

My incubating eggs have a dark ring that looks like a vein around center of egg. Now seems to be no growth. What causes this

 

[MySweetChickens]

it happens when bacteria gets inside the egg

 

[dstinett]

Thanks

 

[Tumbleweed Farm]

That is called a blood ring and I'm sorry to say the embroys

died.