Actually... a chicken and a duck MIGHT be able to have a fertile egg hatch. They are close enough in species, but the offspring would be sterile. Just like when you cross a horse and donkey to get mule. But a duck egg will take much longer to hatch than a chicken egg.
Chicken eggs can be rounded and quite large. It depends on the individual really. My silkie eggs are very round just like you describe. And I have gotten a chicken egg up to 104 grams! Though it isn't my norm.
Hard to say about the you tube video... there is no requirement of real knowledge to post a video about anything you want to!
I know Pheasants and Ginnies can cross with chickens... But have never heard of a duck-chicken hybrid either and I have worked at places that have ducks and chickens free-ranging together and hens of both species brooding eggs. So it is either EXTREMELY rare, or flat out impossible.
Infact, drakes can harm chicken hens when they try and mate with them, due to the hens not really being built for that sorta thing.
....Yes....Totally and absolutely impossible...
I was just saying you can't just plop a green-blue egg layer in with hens you already own that don't and expect them to start laying blue-green eggs.
