Candling eggs is a method used to check the development of embryos inside the eggs during incubation. It involves shining a bright light through the egg to observe the contents, which can help determine whether the egg is fertile and how the embryo is progressing. Here’s a step-by-step guide on how to candle eggs:

Step-by-Step Guide to Candling Eggs

1. Prepare Your Equipment:
   • You’ll need a candler, which is a special light designed for this purpose, or you can use a strong flashlight. Ensure the room you’re working in is dark so you can clearly see inside the egg. We stock several candlers here.
2. Select the Eggs:
   • Candling can be done a few days into incubation (usually around Day 4-7) and periodically after that to monitor development. Choose the eggs you want to candle, preferably those that have been incubating for at least 4 days.
3. Position the Egg:
   • Hold the egg with the large end facing up. This is where the air cell is located, and it’s the best position for viewing.
4. Illuminate the Egg:
   • Place the egg over the light source so that the light shines through the egg. If using a candler, the egg should fit snugly against the light to prevent any light from escaping around the edges.
5. Observe the Inside:
   • Early Stages (Days 4-7): You should see veins spreading out from a central point, and possibly a small dark spot, which is the developing embryo.
   • Mid Stages (Days 8-14): The embryo should be larger, and you may see it moving inside the egg. The veins will be more pronounced.
   • Late Stages (Days 15-21): The egg will appear mostly dark as the chick grows, with a clear air cell visible at the larger end. Movement might still be visible, and the embryo will occupy most of the egg.

6. Check for Signs of Life:

• Healthy Development: Look for clear, well-defined veins and movement within the egg. The embryo should grow larger with each candling session.
• Non-Fertile Eggs: These will appear clear with no visible veins or embryo.
• Dead Embryos: If the embryo has died, you may notice a lack of movement, dark rings inside the egg, or the veins may appear cloudy or less distinct.

Fertile Egg 👇

Infertile Egg 👇

7. Return the Egg to the Incubator:

• After candling, gently return the egg to the incubator, being careful not to jostle or rotate it too much. Proper handling is crucial to avoid damaging the developing embryo.

8. Repeat the Process:

• You can candle the eggs periodically throughout the incubation period to monitor progress, but avoid over-handling the eggs.

Tips for Successful Candling:

• Work in a Dark Room: This helps you see inside the egg more clearly.
• Be Gentle: Handle the eggs carefully to avoid damaging the delicate embryo.
• Keep It Brief: Minimise the time the eggs are out of the incubator to prevent temperature and humidity fluctuations.
• Take Notes: Keep a record of your observations for each egg, which can help you track development and anticipate the hatch date.

Candling is an invaluable tool in ensuring your eggs are developing properly and can help you identify any issues early in the incubation process.

Embryo Development 👇