Don’t give up too easily. Opening and closing the incubator doesn’t have much of anything to do with them pipping unless you’ve been doing it a whole lot throughout the incubation, enough to seriously alter the average temperature or humidity. That’s not likely.
There are a lot of different things that can cause eggs to be early or late. Heredity, humidity, how and how long they were stored, and just differences in the individual eggs. One big thing is the average incubating temperature. If your incubator is running a little warm, they can be really early. I’ve had eggs pipping when I went into lockdown. They still hatched. Some people have reported the eggs hatching a few days late. The 21 days is a target, not an absolute requirement. If mine hatch within 24 hours either side of the 21 days, I consider them right on time.
Then there is just how you count the days. People often get that wrong. An egg does not have a day’s worth of development 2 seconds or 2 hours after it goes in the incubator. It takes 24 hours for the egg to have a day’s worth of development. An easy way to check yourself with chicken eggs is the day of the week you set them is the day of the week they should hatch. If you set them on a Monday, they should hatch on a Monday.
I’ve had eggs hatch a full two days early under a broody, not just in an incubator. Some people have reported broodies being a few days late. It’s not just in incubators you can have these variations. There really is that much variation in when they can hatch.
The reason you have a difference in taking temperatures in a still (or thermal) air and a forced air is that hot air rises. You’ll get different temperatures in a still air depending on what elevation you take that temperature. The perfect temperature for an egg to develop is 99.5 degrees Fahrenheit. The reason the recommendation in a still air is 101.5 degrees Fahrenheit taken at the top of the eggs is that usually gives you 99.5 at the level of the embryo inside the egg and it’s usually easier to take the temperature at the top of the eggs. I agree about the fan. That makes it easier.
I’ve had 25% success rate with shipped eggs. I’ve had 100% success rate with shipped eggs. You normally don’t get really good hatch rates with shipped eggs as with the ones you collect yourself. The eggs undergo temperature variations and are often shaken up quite badly. This doesn’t have anything to do with whether they hatch early or late but can really affect hatching at all.
Fertility is not the only thing that can give you a clear egg that won’t develop. Obviously the egg has to be fertile to start with but nutrition and health of the parent flock plays a part. The hen has to put all the parts of the egg together right or it won’t hatch. There are a whole lot of parts of that egg that need to go together right. How and how long the egg is stored plays a big part too. The embryo is alive from fertilization. If it gets too hot or too cold, or goes through cycles of warm to cool to warm to cool, the embryo can die. Can, not necessarily will. Some of those embryos are surprisingly tough. If it is shaken up too much, you can have problems. Or if it is stored a long time the embryo can die of old age.
Generally if the egg does not develop past the first week, that’s due to something that happened before the egg went in the incubator. If it dies in the last week, that has something to do with your incubation. Analyzing unhatched eggs can really help you figure out what is going on, but there are many different things that can cause them to not develop to start with or die somewhere through the process. It’s not always easy to figure out the real cause.
You can find a chart of what you should see when you candle in the Learning Center above or just do a search online. If you candle as late as you are, what you should see is a solid mass below the air cell. You might see movement, but not necessarily so. Veins are more in the range of seven days.
Something else you can do this late is the float test. This is where you take an unhatched egg and place it on still water in a bowl. Let it settle down. If the egg wiggles on its own, there is something alive in there. Just put it back in the incubator. You don’t even need to dry it off. If it floats dead still, it is dead. Obviously if the egg has pipped you can’t do this without drowning the chick, but if it has not pipped, you won’t hurt it.
One last thing. You do need to calibrate your instruments so you can rely on them. Thermometers and hygrometers can be off a fair amount straight from the factory due to fabrication tolerances. Some are a lot better than others about that. You can be off a full degree or even more and thy will still hatch, just early or late, so you have some wiggle room there, but you should try to get it as close as you reasonably can.
Good luck. Hope this helps a bit.
There are a lot of different things that can cause eggs to be early or late. Heredity, humidity, how and how long they were stored, and just differences in the individual eggs. One big thing is the average incubating temperature. If your incubator is running a little warm, they can be really early. I’ve had eggs pipping when I went into lockdown. They still hatched. Some people have reported the eggs hatching a few days late. The 21 days is a target, not an absolute requirement. If mine hatch within 24 hours either side of the 21 days, I consider them right on time.
Then there is just how you count the days. People often get that wrong. An egg does not have a day’s worth of development 2 seconds or 2 hours after it goes in the incubator. It takes 24 hours for the egg to have a day’s worth of development. An easy way to check yourself with chicken eggs is the day of the week you set them is the day of the week they should hatch. If you set them on a Monday, they should hatch on a Monday.
I’ve had eggs hatch a full two days early under a broody, not just in an incubator. Some people have reported broodies being a few days late. It’s not just in incubators you can have these variations. There really is that much variation in when they can hatch.
The reason you have a difference in taking temperatures in a still (or thermal) air and a forced air is that hot air rises. You’ll get different temperatures in a still air depending on what elevation you take that temperature. The perfect temperature for an egg to develop is 99.5 degrees Fahrenheit. The reason the recommendation in a still air is 101.5 degrees Fahrenheit taken at the top of the eggs is that usually gives you 99.5 at the level of the embryo inside the egg and it’s usually easier to take the temperature at the top of the eggs. I agree about the fan. That makes it easier.
I’ve had 25% success rate with shipped eggs. I’ve had 100% success rate with shipped eggs. You normally don’t get really good hatch rates with shipped eggs as with the ones you collect yourself. The eggs undergo temperature variations and are often shaken up quite badly. This doesn’t have anything to do with whether they hatch early or late but can really affect hatching at all.
Fertility is not the only thing that can give you a clear egg that won’t develop. Obviously the egg has to be fertile to start with but nutrition and health of the parent flock plays a part. The hen has to put all the parts of the egg together right or it won’t hatch. There are a whole lot of parts of that egg that need to go together right. How and how long the egg is stored plays a big part too. The embryo is alive from fertilization. If it gets too hot or too cold, or goes through cycles of warm to cool to warm to cool, the embryo can die. Can, not necessarily will. Some of those embryos are surprisingly tough. If it is shaken up too much, you can have problems. Or if it is stored a long time the embryo can die of old age.
Generally if the egg does not develop past the first week, that’s due to something that happened before the egg went in the incubator. If it dies in the last week, that has something to do with your incubation. Analyzing unhatched eggs can really help you figure out what is going on, but there are many different things that can cause them to not develop to start with or die somewhere through the process. It’s not always easy to figure out the real cause.
You can find a chart of what you should see when you candle in the Learning Center above or just do a search online. If you candle as late as you are, what you should see is a solid mass below the air cell. You might see movement, but not necessarily so. Veins are more in the range of seven days.
Something else you can do this late is the float test. This is where you take an unhatched egg and place it on still water in a bowl. Let it settle down. If the egg wiggles on its own, there is something alive in there. Just put it back in the incubator. You don’t even need to dry it off. If it floats dead still, it is dead. Obviously if the egg has pipped you can’t do this without drowning the chick, but if it has not pipped, you won’t hurt it.
One last thing. You do need to calibrate your instruments so you can rely on them. Thermometers and hygrometers can be off a fair amount straight from the factory due to fabrication tolerances. Some are a lot better than others about that. You can be off a full degree or even more and thy will still hatch, just early or late, so you have some wiggle room there, but you should try to get it as close as you reasonably can.
Good luck. Hope this helps a bit.
