Common reasons why eggs don't hatch - Part 1

Common reasons why eggs don't hatch - Part 1

We all know it can be very frustrating when you invest time and money to incubate a batch of eggs and then get a very poor hatch rate. And so often you are left wondering what in the world went wrong.

We have made it a habit of investigating each of our hatches to determine, to the best of our ability, what went wrong and what went right. We wait until at least a couple of days beyond the due date to ensure any late developers still have a chance to hatch. Then we break open each of the unhatched eggs to see what we can learn. I would like to describe the common issues we find and also those that others in this field of study have found. Please note that this list is not in any particular order.

Unfertile eggs – Occasionally we are given reason to smile when a well-intentioned person has to be reminded that the rooster has a very important role in the process of bringing new chicks into the world. Yes, eggs must be fertilized in order for this whole incubation business to work out. And that’s the rooster’s job. Make sure you have a good, healthy rooster that knows a thing or two about the birds and the bees. (Usually this comes naturally. If it doesn’t, don’t try to intervene. Just get a new rooster.) And yes, roosters get old too. You’ll need to get a new one every few years.

Weak embryo – Some eggs are strong and some aren’t. I’m not talking about the egg shells, I’m referring to what is developing inside. Nature has this way of letting the strongest survive and naturally weeding out the weakest. This is what sometimes happens to a developing embryo inside an egg. The incubation conditions may be perfect, but if the little chick inside doesn’t have what it takes, it will stop developing and die. That’s just how it works folks.

Too moist or too dry – When a mother hen sits on her eggs, her body gives off moisture in the form of moist air, of humid air. The amount she gives off is what the eggs need to ensure they dry out enough, but not too much. I have heard some incubationists (loosely defined as someone who really does know a thing or two about incubating eggs) say that more people kills their eggs because of poor humidity conditions than only other cause. Well, if they are correct, then we should pay attention. The instructions that come with your incubator regarding humidity: follow them!

Infection – There are several barriers that nature has included in eggs to help fight of bacteria. But sometimes, it still gets through. And when it does, it can kill whatever is developing inside. One critical thing we can all do to help eliminate the chances of bacteria killing the developing embryo is make sure we don’t wash off the protective outer layer. This is a layer that the mother naturally adds when the eggs are laid. Keep eggs clean by ensuring the hens have a clean place to lay their pearly whites (or whatever color your hens lay) and gently wipe off any dirty or crud that may be on the eggs with a dry paper towel or something like that. Be sure to sanitize your incubator after each hatch. And candle your eggs every few days to ensure that bad eggs get removed from your incubator.

There are a few more common issues that I will discuss next time.

  1. Rough handling (shipping, etc)
  2. Dormant too long (waited more than 7-10 days after they were laid)
  3. Poor egg turning
  4. Bad temperature