Have you ever wondered how your egg development is going? Candling, when performed after seven to 10 days of incubation, is a great way to monitor the progress of your eggs. It takes a bit of practice, but it isn't difficult.
Devices are designed specifically for candling eggs and these can be purchased, but you really don't need one. You can do it on your own with a bright (preferably LED) white-light flashlight and a dark area. The end of your egg should "seal" against the light – if the flashlight lens prevents this from working, make an adapter tube from cardboard.
Illuminate the egg from below and look for a web-like network of blood vessels surrounding what is the chicken embryo. You may even notice embryo movement.
Clear space and a yolk, or a ring of blood, show the egg was not fertilized or that it died during early stages. It's not unusual to lose 50 percent of your eggs. Eggs that aren't developing properly should be discarded because of the high risk of exploding in the incubator.
Once chicks hatch, leave them in the incubator or hatcher for a day before relocating them to a brooder. Newly hatched chicks get sufficient energy from the residual yolk. All they need for the first few days is a warm environment – there's no need to rush them off to a brooder.