Hi guys so I have a black australorp hen who recently went broody, so she laid her own egg which is unfertilised due to the fact we don't have a rooster whatsoever, we then we put 6 fertilised eggs under her without taking the unfertilised egg which she had laid. 3 days later we manage to get the unfertilised egg off her. We crack open the egg and the yolk was huge! We then crack a normal egg which hadn't been incubated and it was a much smaller difference compared to the other egg, so we are wondering how is this possible we don't even have a rooster???