Eggtopsy - what went wrong with my hatch?

Posted by Susan Lenz on

Eggtopsy - what went wrong with my hatch?

I think everyone at one point has had a hatch that was not 100% successful. And at the end of the day, with the living cheeps in the brooder, you may be left wondering... What happened to the others? What went wrong? When did my chick die? Was it there at all? There's a lot of questions and often you will hear "do an eggtopsy" or someone will say crack the duds open to find out what happened. And you should, but you should have some idea of what you're looking for as well.

So I'm going to attempt to compile a thread with images of eggtopsies myself and others have done and probable causes of death. I will add information as we gather information. It seems morbid at first, but I'd like to think that if you can determine what went wrong, you may be able to prevent it next time. If the learning experience can save even 1 cheep's life, then the guide is a success.

Here we go!


Anyone can crack an egg and look at what falls out, but when there are lives on the line, it's important to be able to keep what was inside as intact as possible. You want to be gentle and observant when you do an eggtopsy, because every piece of information will help you learn what happened. You also want to avoid the mistake of bashing open an egg that may still have a live chick, on those occasions when you just aren't sure.

Before ever performing an eggtopsy, the first step is very careful candling, perhaps even at length. Of course on dark shelled eggs this is difficult, but should still be attempted. You are looking for any sign of movement that is not caused by you moving the egg, so always try to keep the egg stable while candling for this purpose. When candling, make sure that you move the light source to several different locations; note veining, dark areas where the chick is, where the air sac is located, and whether or not the shell appears porous.

If you are CERTAIN you see no movement in the egg, or the egg looks like one of the 'bad' eggs in the first link, then you get to crack it open to find out what went wrong. There are two ways to do this.

For an under-developed egg, this is fairly easy, but has the most potential for explosion, so you will want to first place the egg into a plastic baggie that can be sealed (like a ziploc). You can, of course, do this for any eggtopsy. Once it is secured, gently tap/crack in a circle around the middle of the egg until you've 'zipped' all the way around. Observe any pressure that may cause leakage when you do this; if you've cracked gently enough, nothing should be leaking out UNLESS there is pressure inside the egg, indicating bacteria. You may now pry the egg in half and take a look at what comes out. The first image on this page shows an egg cracked in half using this method.

For a developed egg (one where you are certain there is a chick, or that was close to hatching), you don't typically need to put it in a plastic baggie, but you can do so for clean up and handling sake. For these eggs, you want to be very careful, especially if you believe the chick may still be alive. You will first take a pointed but dull instrument (like a clean nail or a pencil or pen) and tap a hole at the top of the air sac (usually the large end of the egg). This will allow you to see inside the egg without breaching any important membranes. You may actually be able to see the chick moving beneath the membrane when you do this, in which case you should wrap the egg in a warm, damp cloth (do not cover the pip you've made) and place it back in the incubator. If you see no further movement from the chick, however, you can follow the cracking procedure above, making a ring around the egg and pulling the halves apart.

Before I start in on the BAD deaths, here are a couple images of what your chick should look like if everything has gone according to plan. This particular chick died the day it should have hatched, due to a failure to pip. You can see the yolk is pulled in (yes, their bellies and lower abdomen will look distended for a bit). There's no blood or goo stuck to the chick. The feathers are wet, the feet are well formed, and the head is the right shape. The mass next to the chick is normal egg waste- the poop that didn't have anywhere else to go. The blood you see in with it is there because it was attached to the yolk- a minimal amount of blood is normal when the two separate. This gunk is OFTEN still attached to the chick when it hatches and should be cleaned off so they can dry, but don't worry if you find it in the egg shell or during an eggtopsy

*** Edited: Bacteria can enter eggs in various ways. It could have entered inside the hen before the shell was well formed (especially if the one or both of the parents are malnourished or kept in poor living conditions where bacteria growth may be high in their environment). It can also enter through the shell if the shell has been overly cleaned (thus scrubbing away protective layers) or is too porous or is cracked in some way. Blood rings may also form from excessive heat or cold.

Here is an example of 'blood rings' from the inside of the egg. No embryo developed at all, and it ate into the yolk sack, causing a mess (which leads me to believe this blood ring was caused by bacteria). This particular one did NOT explode when cracked, but there was pressure inside of the egg. Blood rings are typical when an embryo died at a VERY early stage.

ABOVE; Here is a example of an embryo that died at a very early stage in development. I tried my best to get a candled picture, but my camera just could not perform. I took this one out for eggtopsy because the veining looked weird and the dark spot (which should be the developing chick) had a strange 'curtain' effect going on that reminded me of blood rings. I observed under candling for several minutes with no movement, and sure enough the embryo had been dead for a while. There was a bad smell when I cracked it and a slight amount of pressure. In this particular case, the egg had been sitting next to the egg pictured above, and this egg had a mottled shell under candling, making it very porous. I suspect bacteria had to do with the death. I want to say this is probably Day 10 or so?

 Here are two pictures of the same chick which I believe died around Day 18-19, which is the last day I was able to observe it rocking. It never pipped at all (I checked for internal pip, but I forgot to take a picture >.< It looked as though the chick never even got to attempt pip, its head was folded under). I took a top and bottom view. Top shows the underdeveloped head, bottom shows the not-quite absorbed yolk. I *suspect* that the humidity was too much for this little guy as the rest of the hatch had some issues related to humidity.



One thing to note is duck eggs need a LOT more humidity than chicken eggs,

The thing about humidity is that it won't kill the chick early on, usually. It doesn't stop them or start them growing; but when it comes time to hatch, how the humidity went through the incubation can really determine whether the chick lives or dies around pip-time. This one was very tiny but well developed. The membranes were tougher than expected. This was the egg I marked as an early death (it stopped all movement internally before the others), but is clearly developed. I am uncertain why this one was different than the others.

This one was positioned incorrectly inside the egg, most likely due to the increased humidity in the bator making it hard for the chick to turn to get in position to pip the air cell. My best guess is that it drown in the last few days because it was unable to get to the air cell in time. This is also the egg which is in the video on the first post.

For the second egg, I actually took pictures as I took it apart and got some nice ones of things to look for if your humidity was too high.


This first picture shows the opaque outer membrane of the egg, which is not to be confused with the inner membrane. It is the inner membrane which would shrink wrap a chick as a result of a drop in humidity during hatch time. Sometimes this outer membrane can turn yellowish once the egg pips, as liquids drop onto it from inside the egg.

I gently broke through the top of the egg (where the air cell was located) to see if the chick had pipped internally or not. It had not pipped and I could not even see a beak, telling me that this one was positioned incorrectly. The lining itself looked all right; it was not too tough, had not turned milky or brown, and was not gummy. You can clearly see the difference in the white outer membrane and the clear, veined inner membrane here

After ensuring that there was no internal pip, I moved to peeling away the shell to see if I could find the beak. I left the inner membrane intact, and without an air cell, it expanded to be egg shaped. Again, the two membranes are clear and distinctly different. You can see the dark eye and the yellow beak here, indicating that the chick was not positioned properly. Also, you can observe here that there is a LOT of liquid under the surface of the membrane. This is a heavy indication that the humidity was too high through incubation. unfortunately you can also see a smear of blood where the chick probably made its last stand against the egg shell, broke a vein, took a breath of liquid

I then peeled away the inner membrane and gently pulled the chick out to get a closer look. Sure enough, the chick looked well developed but was still sporting an only partially absorbed yolk. This can indicate that it died around when it should have pipped internally.

So, there's my too-high-humidity hatch. Hopefully this will help someone determine when their own humidity was too high through a hatch

Here are two images of a duckling that had pipped on the wrong side of the egg entirely. It had made a crack just big enough to shove its bill through, then it had jammed its beak into the hole... and probably died there less than a minute later because it hadn't gotten its nostrils past the opening in the shell and it hadn't made a big enough hole to open its bill to breathe It would have been good to get a pic of how it was when I t was found , but I panicked when I found it and started cracking away shell... but it was too late. Left side shows a (badly) candled pic of where the air cell is in relation to the beak. The second image (below) shows the VERY sticky and gummy membrane surrounding the chick, which is either the reason it couldn't turn to pip right or something which occurred after it died and started to congeal.

Here is an image of an egg I cracked open, along with 3 others. The 3 were dead for reasons I can't explain and probably involve bad luck- they had just failed to pip internally and died. This one though... well, as you can see it's disgusting.

To be honest, the best I can figure is that this egg just started growing meat everywhere in any which way until it died.

Here are two images of two DIFFERENT chicks. This autopsy was performed inside plastic bags, which is why they look glassy. The chicks are clearly underdeveloped, and are sporting fully external yolks. I'm going to say they definitely died before lockdown.

Here is another image of an egg cracked at Day 11. Note the feather development along the back and the size of the eyes compared to the skull. There's also veining around the yolk, and you can see the relative size of the embryo vs. the yolk and other liquids

Here is an image of a day 5 egg broke open. Note the mess of veins that would be attached to the shell and the very tiny dot of embryo. A heart-beat was also visible.

Here is an image of a pigeon chick that has been shrink wrapped in the egg after pipping. Shrink wrapping typically occurs when there is a drop in humidity and temp. This can occur when you open the incubator during lockdown, or if the humidity is not enough despite the closed lid, or the airflow is too much. 

Here is an image of a chick with its intestines on the outside. This can be caused by improper development, genetics, or undue straining by the chick (in the event that the shell or membranes are too thick or the chick is too large and cannot get to the right position so pushing works). The dark brown, gummy inner membrane also indicates a problem with humidity

Here is another image of the same problem. You can very clearly see the dark internal organs on the outside.

Here are two more images of two eggs from the same hatch (and the same hatch as the above picture). Neither had pipped internally. possible causes (from shipped eggs) which center around shipping causing weakened inner membranes, allowing the chick to expand to a size which makes it difficult to turn and pip correctly. This is not a definite answer. Both chicks looked as if they had the correct position to pip (head ducked under the wing, toward the top of the egg/air cell) but for some reason failed to do so. The second image, to me, has the color and looks to be the consistency I have found in my own chicks when the humidity was too high but it could have changed this color if the chick has been dead for more than a couple days (the blood can become old and turn brown inside the membrane and as the membrane begins to break down, the vessels can sometimes rupture, leaving the entire membrane looking brownish).

Here is an image of a chick that pipped through a vein before it was ready to cope with that blood loss.

th that blood loss.

Here is another image of a chick which pipped internally but not externally. It still has a large external yolk, which tells it probably died shortly after pipping as they start to absorb more and more as time passes after pipping. There is liquid but it is not slimy and it is clear, not brown or yellow, meaning this was probably just a case of darn bad luck.

These two more images of a chick who pipped too low to reach the air cell and probably died to drowning in the egg. I'm posting these two to show the inner membrane (stretched out behind the chick in the first pic) and some of what is probably 'normal' white gunk on a chick. I have theorized that it was harmful bacteria, but as there was no bad smell, this is unlikely. It is more likely to be the outer casing of the egg white, portions of the degraded spirals which hold the yolk suspended (called a chalaza), or may even be early excrement from the chick (as it has nowhere to go and the nutrition must be processed somehow!)

Here is an image of a chick whose beak is tucked between its thighs instead of under its wing like it should be in order to pip

Here is an imag of a chick who looks to have died sometime between day 16 and 18. The yolk is still very large (almost the half the size of the chick). the initial inspection looked as if the yolk was ruptured, but the skin of the yolk appears unbroken. By the lumpy shape of the yolk and the other picture provided, the yolk may have been positioned strangely, or else this might be one of those 'it just died' cases.

**** When you buy hatching eggs, after the hatch you should crack open the clears and take note of how many were fertile/infertile. When I hear a lot of feedback saying that X number of eggs were not fertile when I doubt they actually CHECKED that claim. Assuming it's infertile because it did not develop isn't fair. Shipping can damage perfectly fertile eggs and is out of the breeder's hands.

Thought you'd like to see this since so many have asked how to tell if their eggs are fertilized. 

The first picture is an INfertile egg.

On this one, you can see the ring, indicating fertility. This is caused by cells in the center of the blastoderm dying off and leaving a cleared out area, making that bullseye appearance. Not all are as clear as this one is, but you get the idea.

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