Fertilize eggs under a broody chicken.

[Chickenheadmate]

Hen has been sitting on eggs for like 3-4 days now? Has any mayor development happened to where it’s not recommended I eat? I’m not into eating embryos or anything that already started to develop

 

[SilverBirds]

There would be development in the eggs at this point if they are
fertile. This is one of my duck eggs on day three. If you were to crack it open, you'd find a tiny embryo in the middle of a ring of veins.

 

[SilverBirds]

Are you wanting to your hen to hatch eggs? Have you considered breaking her of her broodiness?

 

[Ridgerunner]

If the eggs are fertile you should see blood vessels. Some body parts like eyes, heart, and limbs are just starting to develop.

If the egg is laid in the morning and a broody hen sits on it all day you can eat it without seeing anything as long as you collect it that evening. Any longer than that you could see something when you open it.