Who knows how old this embryo is? + why?

[BDutch]

A friend of mine is hatching eggs with an incubator.
She had 3 eggs with embryos that died in the same stage of incubation and send me this picture wondering if knew more. Unfortunately I don’t. But there must be someone on BYC who knows the answer.

• How old is this embryo?
• What could be the reason why this embryo died?

 

[Abrahen Lincoln]

You can estimate the age of a chicken embryo by looking at its stage of development.

Early development

• Day 1: Embryonic tissue appears
• Day 2: Tissue development is more visible
• Day 3: The embryo's heart starts beating
• Day 4: The embryo's eyes become pigmented
• Day 5: The embryo's elbows and knees appear
• Day 6: The embryo's beak begins to form

Mid-development

• Day 7: The embryo's comb starts to grow
• Day 8: Feather tracts are visible
• Day 9: Claws appear
• Day 10: Nostrils appear
• Day 12: Toes are fully formed

Late development

• Day 16: Feathers cover the embryo's entire body
• Day 19: The yolk sac is drawn into the embryo's body cavity

You can also tell if a chicken egg contains a live embryo by looking for blood vessels inside the egg. Blood vessels are usually visible within 7 to 10 days of incubation.

 

[Yardmom]

I haven't opened eggs at that stage but it is less than a week. As far as what caused the deaths it hard to say. External things include too high of temperature or shaking. More likely just that the chick didn't have all the right inputs (or genetic combinations) to continue to grow. Unfortunately not every egg is suited to grow a chick.

 

[Abrahen Lincoln]

Oh, my apologies.

 

[BDutch]

I haven't opened eggs at that stage but it is less than a week. As far as what caused the deaths it hard to say. External things include too high of temperature or shaking. More likely just that the chick didn't have all the right inputs (or genetic combinations) to continue to grow. Unfortunately not every egg is suited to grow a chick.

I think it’s older. Maybe about 10 days according to this article. But even with those day to day pictures it’s hard to say for sure.
https://www.thepoultrysite.com/articles/embryonic-development-day-by-day

Thanks @Perris for posting this in Shads thread.