The Basics of Duck Candling 

Tell You Even though the technology is now so advanced that a breeder can hatch eggs using state-of-the art incubators instead of broody hens, not all eggs incubated are fertile to hatch. One way to identify the fertility of eggs is through the process of duck candling. Infertile eggs can be identified and can be easily removed from the whole batch to prevent contamination.

Whether it is chicken or duck candling, almost all eggs can be candled to identify its fertility. It is the simple process of shining on an egg with a strong illumination source, such as a strong flashlight, to check whether the egg is fertile or if the embryo is developing. It is usually easier to candle white eggs than speckled or dark colored eggs. You can purchase a commercial egg candler or make a simple tool to perform the chicken or duck candling. All you need for a DIY candling tool is a dark surrounding and a strong flashlight. Just shine the light on the egg held up so that you can see through the egg.

>>Check out our how to guide: DIY Incubator for Ducks<<

Duck Candling: What you see 

During the duck candling process, be careful not to examine the egg for more than 10 minutes at any one time to avoid adverse effect on the development of the embryo.

* Faint yolk right in the egg center with some air space on one end, indicating a freshly laid egg that is unfertilized.

* Thin red veins in the midst of a watery yellow liquid which indicates a fertilized egg that is developing.

* Opaque mass, this is an indication of a fertilized egg where the chick or duckling has grown big enough to fill the egg, blocking the light.

* If the egg does not hatch at the due time, or there is a huge air bubble at one end of the egg, this is an indication that the chick has died. But if the candling shows no yolk but a huge air bubble, this indicates an unfertilized egg which should be disposed.

Whether it is chicken or duck candling, the process can be performed once in a few days to check on the embryo’s development as well as to prevent bacteria and germs from breeding and spreading from broken shells.

>Read More: Choosing the best Duck Incubators for your Hatching needs<