Candling is the process of placing the duck egg up to a light source to observe the development of the embryo inside the egg. Candling allow you to monitor the embryo’s development within the egg and to determine if the egg is fertile or infertile. When you candle a duck egg, you are looking for specific indications of the growth of the embryo inside the egg.
For example, different type of duck eggs will contain different development timelines for the embryo inside of there eggs. In order to correctly candle duck eggs, it is important to have an understanding of the different development timelines of duck eggs. During the first week of incubation, the goal is to ensure that an embryo is developing inside the egg.
How to Candle Duck Eggs and Check Development
During the first half of the first week, the embryo in the duck egg is too small to be seen, so there will be an air pocket and yolk inside of the egg. During the middle portion of the first week, a network of red veins will appear inside the duck egg, as well as a dark spot inside of the egg that represent the heartbeat of the developing embryo. If you candle the duck egg after seven days of incubation and no heart beat can be seen, the egg is likely infertile.
You should remove infertile eggs from the incubator as they could potentially create harm to the healthy duck eggs within the incubator. Between day nine and day eighteen of incubation, the embryo inside of the duck egg will grow in size. The veins inside the duck egg will become thicker, and there will be a dark mass inside of the egg that represents the embryo as it gain size and begins to exhibit movement.
As the embryo gains size, moisture will naturaly evaporate from the egg. This evaporation will cause the air cell inside of the egg to grow in size. Monitoring the air cell allows for an understanding of the humidity of the incubator.
If the air cell is too large or too small, you should adjust the humidity within the incubator to ensure proper development of the embryo inside of the duck egg. Between day eighteen and day twenty-five of incubation, the duckling will take up the majority of the space within the duck egg. The air cell will be approximately one-third of the volume of the duck egg, and the duckling will move less frequent within the egg as it prepares to hatch.
On day twenty-five, you should increase the humidity within the incubator, and you should stop the incubator from turning the duck eggs. This period is referred to as lockdown when the incubator is kept closed to the duck eggs to maintain the humidity and the temperature of the incubator. A duckling will first make a small hole in the air cell of the egg.
Following this, the duckling will make cracks in its shell, referred to as a zipper. This process can take between twelve and thirty-six hours to complete. One of the most common mistake that people make when incubating duck eggs is opening the incubator too frequently to observe the duck eggs.
By doing so, the temperature and humidity within the incubator will drop. Should the temperature or humidity drop too low, the ducklings may be harm. Only open the incubator for brief periods to candy the duck eggs.
Understanding the difference between a duckling that is resting and one that is not developing properly is important. For example, a blood ring inside of an egg indicates that the embryo has died within the egg. Different breeds of duck will exhibit differences in their incubation and candling requirements.
For example, mallard duck eggs are smaller than Muscovy duck eggs. In addition, Muscovy duck eggs require five additional days of incubation to hatch compared to mallard duck eggs. During the final stages of incubation, muscovy duck eggs require more higher humidity levels than mallard duck egg requirements.
Pekin and Khaki Campbell duck eggs require incubation periods similar to mallard duck eggs. However, the thickness of the shell of Pekin and Khaki Campbell duck eggs may differ from that of a mallard duck egg. These differences in breed must be accounted for when incubating different types of duck eggs.
The ability to candle duck eggs allows for the detection of small changes in humidity before they create harm to the duckling. By candling the duck eggs, you can remove those that do not exhibit any movement of their embryos from the incubator. Through the repeated process of candling, an expert in incubation will gain an understanding of the pattern of their incubator and the specific pattern that each of their duck eggs exhibit.
Through the repeated process of candling their duck eggs, individuals will gain an understanding of the continuous process of embryonic development within the duck egg.