Strawblady2000
06-06-2006, 05:10 PM
Hello!
I'm posting this to respond to greg's inquiry about examining eggs when the chicks have died in the shell. I hope some of the descriptions are not too graphic. If so, please edit or let me know and I'll do so. :)
There are many reasons this can happen and unless one is tracking the eggs with regualr candling, it isnt noticed until hatch dates have come and gone with no hatchlings.
Here are a few things I take note of when examing the eggs.
First, if eggs fail to develop, I try to determine if the eggs were simply infertile or if they started very early on to develop but died within a couple of days. Eggs that tried to develop sometimes have a small red ring around them, but do not make it past that stage. Causes for this can be from improper incubation, lethal genetic factors, or infection that penetrated the shell.
When a chick develops normally, but dies in the latter part of incubation, most times it is due to chilling of the egg or from the humidity being too low. Sometimes, if the egg is chilled within the first 2/3 of incubation, it may not be evident, as the chick MAY continue to develop, but fail to make it to hatch.
When examining a latter stage egg, find the end of the egg with the air cell. Gently tap open the egg shell on the end where the air cell is and peel it away. You will see a membrane that separates the chick from the air cell. The chick must break through this membrane in order hatch.
If you notice the cell is not broken, chances are that the egg was chilled and the chick may have continued to slowly develop, but did not have the ability to break through the membrane.
If you notice the chick protruding into or to have broken through the membrane, but dies after doing so, chances are it died from lack of humidity, as the dry conditions will have caused the chick to stick to the inside of the shell, preventing it from rotating itself to peck itself out. If you further pick the shell off, you will notice the chick will be stuck to the remainder of the egg. The fluid surrounding the chick, if any, will be very thick. Many times, even if the chick manages to crack the egg on its own, it will be unable to finish the job. The parents may assist, only to end up injuring the chick as it tries to pick the shell from the baby. This is where many pipping deaths occur as well. If you were to continue picking off the shell, trauma to the chick's body would most likely occur, as the shell would appear nearly glued to it.
In both of these cases, the air cells will be a bit larger, as a) the chick is not growing any longer to consume the space of the air cell and b) there is not enough moisture in the egg, causing the contents to become concentrated or thickened due to lack of water.
Another type of dead-in-shell is also called "liquid egg". This usuall happens during the middle portion of incubation. There are many causes, but a sure sign is when you rotate the egg, the contents will sink to the bottom of the egg. As you turn it, the dead chick and liquid will slide to the bottom, no matter what angle you hold the egg.
Hopefully, these clues can help to diagnose or address any issues when it comes to dead in shell or pipping deaths. While only a veterinary examination can be 100% sure, sometimes key signs can be used to help adjust things on your own.
Also, a word of caution. I ONLY do this if I am positive the eggs are dead. If your hatch date has passed only by a few days, dont necessarily jump to conclusions, as the chicks may be alive and well. Also, unless you regularly candle to check progress of development, it is very difficult to tell unless you are experienced in identifying shell color, etc., as eggs darken as the chicks develop, but turn an odd shade of gray that takes experience to recognize. Sometimes candling at a late stage does not reveal much, other than an egg that looks full with a chick, lol, but sometimes one can see the chick's movement within. If you do not see movement, don't assume the chick has died.
Many people leave well enough alone, but this is just a tool to help by giving you more information.
I'm posting this to respond to greg's inquiry about examining eggs when the chicks have died in the shell. I hope some of the descriptions are not too graphic. If so, please edit or let me know and I'll do so. :)
There are many reasons this can happen and unless one is tracking the eggs with regualr candling, it isnt noticed until hatch dates have come and gone with no hatchlings.
Here are a few things I take note of when examing the eggs.
First, if eggs fail to develop, I try to determine if the eggs were simply infertile or if they started very early on to develop but died within a couple of days. Eggs that tried to develop sometimes have a small red ring around them, but do not make it past that stage. Causes for this can be from improper incubation, lethal genetic factors, or infection that penetrated the shell.
When a chick develops normally, but dies in the latter part of incubation, most times it is due to chilling of the egg or from the humidity being too low. Sometimes, if the egg is chilled within the first 2/3 of incubation, it may not be evident, as the chick MAY continue to develop, but fail to make it to hatch.
When examining a latter stage egg, find the end of the egg with the air cell. Gently tap open the egg shell on the end where the air cell is and peel it away. You will see a membrane that separates the chick from the air cell. The chick must break through this membrane in order hatch.
If you notice the cell is not broken, chances are that the egg was chilled and the chick may have continued to slowly develop, but did not have the ability to break through the membrane.
If you notice the chick protruding into or to have broken through the membrane, but dies after doing so, chances are it died from lack of humidity, as the dry conditions will have caused the chick to stick to the inside of the shell, preventing it from rotating itself to peck itself out. If you further pick the shell off, you will notice the chick will be stuck to the remainder of the egg. The fluid surrounding the chick, if any, will be very thick. Many times, even if the chick manages to crack the egg on its own, it will be unable to finish the job. The parents may assist, only to end up injuring the chick as it tries to pick the shell from the baby. This is where many pipping deaths occur as well. If you were to continue picking off the shell, trauma to the chick's body would most likely occur, as the shell would appear nearly glued to it.
In both of these cases, the air cells will be a bit larger, as a) the chick is not growing any longer to consume the space of the air cell and b) there is not enough moisture in the egg, causing the contents to become concentrated or thickened due to lack of water.
Another type of dead-in-shell is also called "liquid egg". This usuall happens during the middle portion of incubation. There are many causes, but a sure sign is when you rotate the egg, the contents will sink to the bottom of the egg. As you turn it, the dead chick and liquid will slide to the bottom, no matter what angle you hold the egg.
Hopefully, these clues can help to diagnose or address any issues when it comes to dead in shell or pipping deaths. While only a veterinary examination can be 100% sure, sometimes key signs can be used to help adjust things on your own.
Also, a word of caution. I ONLY do this if I am positive the eggs are dead. If your hatch date has passed only by a few days, dont necessarily jump to conclusions, as the chicks may be alive and well. Also, unless you regularly candle to check progress of development, it is very difficult to tell unless you are experienced in identifying shell color, etc., as eggs darken as the chicks develop, but turn an odd shade of gray that takes experience to recognize. Sometimes candling at a late stage does not reveal much, other than an egg that looks full with a chick, lol, but sometimes one can see the chick's movement within. If you do not see movement, don't assume the chick has died.
Many people leave well enough alone, but this is just a tool to help by giving you more information.