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How to Candle Eggs to Check for Fertility!

How to Candle Eggs to Check for Fertility!

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hblife Bright Cool LED light Egg Candler

hblife Bright Cool LED light Egg Candler

The question is how to candle eggs to check for fertility? If you ask me what brings excitement in keeping chickens, I will gladly point out to candle my chickens’ eggs. This is the most fascinating task especially when the embryo inside the egg is developing. Candling comes in the wake of incubating and eventually hatching new chicks. If you are a new chicken keeper, you must be wondering why this poultry practice is vital. Read on to understand the reasons behind candling chickens’ eggs.

Why should I candle my chickens’ eggs? There are many reasons why we candle  my chickens’ eggs. Out of the many reasons we know today, checking the quality of eggs seems to be the most crucial one. The rest come in just to ensure that the eggs are suitable for incubating and hatching.

Before we analyze each reason in detail, let’s first get to know when exactly is egg candling. Simply put, this is the name poultry farmers use to refer to the practice of observing an egg under a source of light. The egg is examined primarily to check if it is fertile or not. Also, this task aims at assessing the quality of an egg before incubating it. 

Speaking of incubation, an egg has to undergo candling at subsequent stages to know if the embryo is developing normally. This is important because it helps you to look forward to a certain number of newly hatched chicks. Besides, it enables you to eliminate those eggs with embryos that are developing poorly to avoid future losses. In essence, candling is a critical skill, especially when incubating your own eggs at home.

The technique is called candling to remind you of how it was done before the invention of modern candlers. From the name, you can tell that it involved the use of candlelight to see through an egg. 

During the process, an egg was held over the candle flame inside a darkened room. Such an environment allowed an observer to have a good view of the egg’s contents. Although this process was not so perfect, it paved away for the modern candling techniques we use today.

Understanding the Egg Candling Process

  • As mentioned earlier, it is wise to keep track of how your chickens’ eggs are developing. The process lets you see what is happening inside an egg in a limited way. 
  • However, it also allows you to choose only the best eggs for incubation. All you need is to use your finely tuned skills to get a good idea of problems or progress inside the eggs.

What NOT to do while candling:

      1. Not candling your eggs daily. Doing so can possibly have a negative impact on the growth and development of chicks due to frequent interruptions.
      2. Do not candle soiled or dirty eggs

Reasons To Candle Your Chickens’ Eggs

  • Candling is necessary just before hatching eggs. The fact is that you can never have a 100 percent hatch rate no matter how you try. Some eggs will be fertile while others will not and this is a matter of concern to all chicken keepers. 
  • Non-fertilized eggs are yolkers while quitters are eggs that stop developing during the incubation period.
  • Also, egg candling helps you to identify and get rid of quitters and yolkers during the incubation period. If you don’t remove such eggs from the incubator, they will start to rot and burst. As a result, they will contaminate the rest of the eggs with bacteria. Since you don’t want such a thing to happen, it’s prudent that you consider performing the egg candling procedure. 
Chicken Egg Candler

Chicken Egg Candler

The Correct Egg Candling Equipment

  • Egg candling requires the use of specially designed equipment. These tools don’t need to be fancy or sophisticated. 
  • Keep in mind that the main requirement here is a source of bright light and eggs. The brighter the light, the better it is. In this regard, the light should come from a smaller opening than the egg’s diameter. 
  • To make the process more effective, you will need a very dark room. A darker environment allows you to see most of the details inside the egg. From these details, you can easily tell the progress of embryo development at different stages of incubation.
  • So, where do you obtain the egg candling equipment?
    1. You get specific chicken egg candling equipment from any poultry stores at affordable rates. Such devices look like flashlights and are powered using a plug-in cord or batteries. 
    2. You can make your egg candling tools at the comfort of your home using a 60-watt light bulb. Place the bulb inside the coffee can and pierce the hole through it. Make sure that the hole is smaller in diameter compared to that of an egg you want to test. Normally the whole is 1 inch/2.5 cm to allow the bright light to pass through an egg. 
    3. Alternatively, you can use a bright flashlight and a piece of cardboard cover with a 1-inch hole in the middle to accomplish this task. 
    4. On the other hand, you can turn to a more sophisticated and high-technique to make egg candling more effective. Although expensive, this option (also referred to as Ovascope) uses a rotating stand where an egg is placed for candling. Once in place, the egg is covered to block out ambient light. This gives a more detailed view of the contents inside the egg that you are testing. 

Appropriate Candling Schedule

  • You don’t need to candle the eggs any time you feel like doing so. Instead, you should carry out this exercise just before you take your eggs into the incubator. 
  • Initially, you won’t be able to view anything. You will not be able to know bad eggs and good eggs. But you will have an idea of how an undeveloped egg appears. This information is useful when making some comparison between yolkers and quitters in the future. 
  • So, what should you look out for?
  • It is helpful to search for any small cracks that are not visible to your naked eye. Tiny cracks on eggs are more likely to allow harmful bacteria to get into the eggshell. The presence of these bacteria can affect the progress in the development of an embryo. Therefore, you should take note of a cracked egg to monitor its progress in the future. 
  • Some people candle eggs frequently during the incubation period but this is not the best way to go about it. If you are one of them, it is advisable to wait until one week is over before candling again. 
  • Below are two major reasons why you should candle the eggs after seven days:
    1. All eggs are sensitive to changes in temperatures. If you constantly move them in and out of their incubator, you may negatively affect their progress. Such cases are common especially during the early stages of their incubation.
    2. Before the seven days are over, the eggs may not have developed that much. As a result, it will be extremely difficult to tell the difference between bad and good eggs.
  • After candling on the seventh day, you need to let the eggs stay undisturbed until the fourteenth day. At this time, you will be in a better position to double-check all eggs and find out any problems. In case there are no signs of development in some eggs, you may discard them as soon as possible. Such eggs will never hatch even if you let them stay in the incubator throughout.
  • Beyond the sixteenth day, you should not candle the chickens’ eggs. Remember, the eggs should not be turned or moved because they are about to hatch. Additionally, the embryos are already developed in such a way that they fill every space inside the egg. And you will not be able to view anything of importance as far as egg candling is concerned.
Magicfly Digital Fully Automatic Egg Incubator

Automatic Egg Incubator

Related Questions

Will chicken egg candling determine the fertility of the eggs? The astounding answer is no! The only way of knowing if eggs are fertile is by opening their shells after a few days of incubation. Or you may candle them one week later during the incubation to see more details inside the shell. Fertile eggs will show a developing embryo sometime when they are incubating.

How frequently should I candle my eggs? The best time to candle the eggs is when you are placing them in an incubator. After a week you can candle them again to differentiate between the good and bad eggs. You can carry out this process until day 17 of your eggs’ incubation. This should tell you that candling needs to take place at least three times before the eggs hatch.

In Conclusion:

The main purpose of candling chicken eggs is to prepare them for hatching.  Candling requires a powerful source of light to illuminate through an egg so you may view its contents. This practice will help you single out yolkers and quitters at the right time during the incubation period. In return, you will be able to incubate only the right eggs.

Below is a Pinterest friendly photo…. so you can pin it to your Chicken Board!!


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