To candle them before incubation starts does not affect the embryo, since it hasn't started developing yet.
What worries me is when folks candle in the first few days of incubation, when the embryo is just getting started and very fragile. I don't think it's a good idea at all to candle in the 1st 3-4 days or the last 3 days.
Also, when candling you should be careful to just lift the egg to the light and place it gently back in the bator. You really don't want to turn it over and over searching for a moving "baby". That causes issues with the vein network and I think people forget about the intricasies of the developing eggs.
Jody
What worries me is when folks candle in the first few days of incubation, when the embryo is just getting started and very fragile. I don't think it's a good idea at all to candle in the 1st 3-4 days or the last 3 days.
Also, when candling you should be careful to just lift the egg to the light and place it gently back in the bator. You really don't want to turn it over and over searching for a moving "baby". That causes issues with the vein network and I think people forget about the intricasies of the developing eggs.
Jody