Shrink Wrapped or Sticky Chicks? Why Chicks Have Difficulty Hatching

By Chrissy in CA

Hatching eggs isn’t always as easy as setting eggs in an incubator, waiting 21 days, and waking up to chicks on the twenty-first morning. There are a few things that can go wrong – especially in less-expensive incubators. Humidity and temperature issues can cause chicks to become “shrink wrapped” or to be overly-sticky at hatch.

The highest risk of shrink wrapping is after the eggs have externally pipped, have already been in lock down with high humidity... and then the incubator is opened for some reason. If the ambient humidity in the room is lower and the temp is cooler than the humidity and temp are inside of the incubator, (which is often the case) then opening an incubator lets a rush of cool, dry air into the incubator that exchanges with/replaces the warm moist air in the incubator, and does this inside the eggs as well. That is what dries out and shrinks the membranes. The membranes were moist, and then quickly lost moisture and shrank when the cold dry air rushed in. This is why incubator instructions always clearly state not to open the incubator until the hatch is completely over. 

Shrink wrapping can also happen to eggs that have only internally pipped, but is a little less likely and less damaging since the air and humidity can't exchange as quickly thru an un-pipped shell. This is why we can get away with waiting to lock down eggs until they have internal pipped and we can also candle prior to lock down without doing damage. Personally, I wait until I see internal pips before locking down... I have never had any shrink wrapping issues doing this.

High temps can also cause shrink wrapping, especially in forced air incubators with fans when there is not enough humidity in the incubator. Moisture is continually being lost at a time when the chick needs a little extra moisture to keep the membrane from becoming leathery/tough, when the chick needs to stay slick enough to spin in the eggs and also when the extra moisture is needed to keep the shell a little softer.

Sticky chicks are usually caused by overly high humidity during incubation that did not allow the chick to grow as large as it should have or let the egg lose enough moisture as the chick developed, so at hatch time those chicks are coated with more liquid (albumen) than they should be. A sticky chick's movement is restricted, but the stronger chicks usually manage to hatch ok (just extra sticky). The weak chicks will expire trying to hatch because they just don't have the strength. if they can't spin, and can't zip, they expire. Sometimes that extra sticky liquid can clog the chick's nostrils (aka drowning the chick), and the sticky liquid can also cause the opening of the internally pipped membrane to glue down onto the chick's nostril shortly after they have pipped internally, suffocating it.

(This chick was "sticky" at hatch, but is now a healthy, happy pullet.)

This is why it is important to know your incubator – practice managing the temperature and humidity prior to trying to hatch chicks. If you are experiencing losses at hatch, chances are it has to do with one of the above factors. Invest in a good hygrometer (or 2) and good thermometer(s) to keep inside your incubator – checking them regularly throughout incubation and hatch should alert you to any issues.

To hatch chicks, an incubator should remain at about 99.5 °Ffor all 21 days. Many people use a “dry incubation” method where humidity levels are kept lower (16% - 40%) up until the eggs internally pip, while other people keep their humidity a bit higher (40%-50%) throughout incubation.

At lockdown or after the chicks have internally pipped, humidity should be raised to about 65% and the incubator should not be opened until the last chick has hatched... or they'll chop your fingers off with a light saber...

(Just kidding! But I did think this picture was cute - the reflection of my flashlight used for candling gave the appearance my chicks were Jedi knights.)

Hope this helps, and happy hatching!

Chrissy in CA -

(Photos and lame humor by Leigh) 

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Great Tricks for Using Inexpensive Incubators - One Woman's Incubating Efforts‏

By Jane, AKA Mumsy

 

Artificial incubation of chicken eggs is nothing new. Since earliest history keeping there are accounts on how this was accomplished. From the earliest Egyptians as recorded by Aristotle in 400 BC. Those incubators were made of mud brick and look like enormous kilns. The exactness of the eggs temperature was tested by holding the egg to the eye lid. This skill is so precise it is still practiced and handed down through generations. These methods and kilns are still used to this day. I have read that hatch rate is very often 80%! Not bad. Not bad at all.

Since mankind started domesticating poultry, it became apparent waiting for a broody to get in the mood wasn't going to supply enough eggs and chickens for a growing population year round. Incubation has gotten a bit easier for us in this day and time. With so many more folks wanting to hatch just a few eggs or hundreds, electricity and finely calibrated thermometers and hygrometers helps a lot. Then why is it so difficult with some incubation methods and incubators?

This article is about the way I go about it using an inexpensive Little Giant Styrofoam incubator. It could hold forty eggs with an automatic turner but I don't need that many chicks for my home use. I usually set half that amount or less.

First things first. Setting it up in place where there is no forced heat source from my electric heater. If I had a choice it wouldn't be near a door that is opening and closing to the outside as well. To cut down on drafts the incubator is set into the bottom portion of the card board box it came in.

I also poke extra holes evenly distributed on the top of the incubator. Being careful to make them the same size. The extra ventilation is a good thing. This is done before setting eggs.

For me keeping written records comes naturally. No worries about second guessing age of eggs, who laid what, when to turn the eggs, and all the other little details that will help me with future hatches.

I collect eggs for hatching as soon as I can. Warm from the hen is my favorite. I keep all nest boxes clean. If there may be a small poop spot, I clean it off gently with an emery board. If it doesn't sand off easily, I don't put it in my incubator.

The eggs go immediately into my house into a dark cool closet. This is where writing the date collected on the egg becomes important. During candling and hatch, I can tell at a glance how old each egg is. If an egg becomes a quitter, that date on that egg goes into my notebook. Good way to know if I'm setting eggs that are too old.

I keep a thermometer/hygrometer next to the egg carton. It has to read 58 to 60 degrees with 30% humidity reliably before I store the eggs. A dark +00

wax crayon is attached to the carton with a ribbon. I mark each egg at the large end with the initials of the hen (I would use breed or color if applicable) the date I collected it and an X and O on each side. I can't read pencil through my incubators window and I don't like the idea of ink or other unknown marker on my porous egg shell. Wax crayons are harmless and I can and have used different colors for different hens or breeds.

Two days before I have my batch of eggs collected, the incubator is plugged in and I put all my necessary items inside it. This is the most important time for me. Once eggs go in, the last thing I want to be fooling around with is temp/humidity readings and whether I forgot to add something. 

The inside of my incubator looks crammed. Well... It is! But everything has a reason or purpose. To help keep the temperature steady or keep eggs separate at hatch. This is what I use and why.

Five thermometers. One has a hygrometer. It is the best I could afford in a pet store with the reptile cage supplies. The next best is the meat probe thermometer. I keep the probe inside my homemade water weasel for accurate inside egg temp reading.

The water weasel is nothing more than a vacuum sealed bag full of water. I used a hot glue gun to double it over itself. Hot glue, plastic bag, water, and bare fingers are tricky together. If you make this, be very careful or you will burn a hole in the bag, burn your fingers and generally have a painful mess. Don't ask how I know this.

The glass jam jars with tightly fitting plastic lids are heat sinks. I may try filling them with clean stones someday. Water works. I have not had big dips in temperatures with this set up. The filled water jars help with that, as does that bag of water with my probe.

The 1/4 hardware cloth cage is held together with zip ties and I used electrical tape on the sharp edge. This goes in at lock down. When progeny testing chicks, this cage keeps babies from mixing together. 

The shelf liner is disposable. I like it on top of the wire bottom in the incubator. After hatching I take it out and toss it. Keeps a lot of the mess off the wire. 

My current set of eggs is on dry hatch. No water in the well channels. I live in the Pacific North West. It's wet here. A lotof the time. My humidity reading is holding steady at 33%.

At lock down, a few small sterile sponges will be lightly wet with warm distilled water and added in the corners of the incubator. This will bump humidity to 50% to 66%. Hatches with higher humidity than this have been disastrous in previous attempts for me. I get chicks to hatch but not full batches.

 

Humidity too high = too large chicks that drown in the shell before or after piping. No room inside the shell for all that chick and all the liquid. It's a sad end to other wise good development, and one I do not want to ever repeat.

When everything inside the incubator is set up and the temp is reading 100 degrees on at least four of five thermometers, the humidity is holding at 30 to 33% for at least 24 hours... Then I place the eggs inside.

The easiest way to calibrate a bunch of thermometers is set them together on a table in the room with your home thermostat. If they all read the same, you’re good to go. Some say to dip them in ice water until they all read 32 degrees. I haven't tried that.

Two thermometers are placed on the floor of the ‘bator on either side of the eggs. Two are set at egg level either side. The probe in the water weasel is set top egg level. When I turn my eggs, they are moved around the ‘bator. No egg sits more than six hours in the same spot. 

The first set will be eggs in the upright position. I don't open the incubator or turn the eggs for the first 24 hours.

In my notebook and on my calendar kept next to the incubator, I mark the day set. Each time I turn the eggs, I mark my notebook to which side (“X” or “O”) and the time. This is not something to worry over much, as long as they are turned at least a few times a day. It only takes me a minute to hand turn thirteen eggs. I keep a damp sponge in a cup next to the ‘bator and moisten the tips of my fingers before turning. Marking in my notebook gives me something to do. It beats staring at eggs through that little window. Yes. I have been known to stare at eggs. I should be sweeping the floor and dusting the china but staring at eggs for twenty-one days seems to be what I do best.

I mark on my calendar when to candle on the seventh day, fourteenth day, and eighteenth day. I just candle the three times. I take out half the eggs. Close the lid. Do the candle. Replace those eggs and take out the other half. It's after candling that takes the longest for the inside ‘bator temperature to come back up. I NEVER touch that adjuster if I can at all help it! The temp will come back up. Just walk away and try not to look for at least an hour. Here is where that probe thermometer and water weasel come in really handy. In my set up it has never dropped below 98 degrees after candling. The other thermometers may take a little while to come back up but that probe tells me the inside temp of the eggs is holding steady and safe. It takes a lot of worry a way. I lock down the incubator on the eighteenth day after one last good look at the eggs.

When that probe thermometer in the water weasel dips too low, that's when I pay attention. I will turn the room thermostat up a notch. I'll turn on an over head light above the incubator. But... I never touch that adjustment knob.

My candler is the brightest LED flashlight I could find at the local hardware store. Works great! But it has lots of other weird and alarming settings that nearly blinded me the first time I used it in the dark water closet. Flashing red lights and strobe beacons startled me good! Good thing I was sitting down!

There are many types and brands of incubators available. Some are truly excellent. Little is needed to attend them once they are set with eggs.

This article is geared to those folk like me. Hands on, attentive to details, and want to save a little money and not worry so much.

Artificially incubating eggs with cheapo set ups is fun. Especially when you get those details right. Things can and do go wrong but that's life. Happy hatching!


Cheers!

Mumsy

Leigh Says:

As a side note, on Mumsy’s advice, I have modified my own Little Giant incubator and am having far, far better results than my last attempt at incubating! No more 3 degree temperature swings and so much less worry!

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