Help....I think air sack is too big!

[micheleomal]

Obviously a newbie here. This is my first hatch. I am making it difficult on myself with a staggered hatch (4 actually) but I do have a separate incubator for lockdown. The problem is, at 12 days my oldest eggs have air sacks the size of 18day eggs. I live at 5400 ft elevation. The eggs came from much lower elevation; Florida, TN and Ga. I do have 8 from near me though. I have THREE hygrometers. I calibrated all three at different times using the salt method. 1 was +3%, 1 was -10% off and one was spot on. Put them in the incubator, add a tiny bit of water and the first two read 40% (taking into account the +/- factors). I order the third one. It just came in. I calibrate it the same way, put it in the incubator and it reads 10% humidity!! Now normally I would take this one and throw it out the window but when I candled those first eggs, the air sack is very large. This is SO frustrating. I have 29 viable eggs. The oldest ones have bouncing baby chicks inside and I'm afraid that I have already destined them to a shrink wrap hatch. Should I increase the humidity for the rest of the incubation (before lockdown). Can you actually DECREASE an air sack or is it too late? Pulling my hair out here at 5400 ft! And I want to thank eveyone on this forum for all the tips and advice I get from here.

 

[dretd]

Hi Michelomal!

First of all, welcome to the fun and challenging world of incubation

I am at 5000 ft, not too far off from your situation. I don't think the altitude will be your problem, rather that you are new to the game and don't have experience with your incubator plus you are using shipped eggs. For me, I expect that my hatch rate will be very low from shipped eggs and am delighted with a 20% hatch rate. Not trying to be negative...just keeping it real!

More info about your incubator--brand, whether it has a fan, are you hand turning or have an autoturner, is it new, what type of wells for water does it have? Then more info about its location--does the room you are incubating in have a stable temp, have you checked its humidity?

I am concerned that you calibrated the hygrometers but they don't match each other--perhaps try calibrating at 99 degrees next time would give you better results. Well, got to move on from where you are this time around. IME, digital are not as accurate as analogues and usually read low by a lot. I have one that reads 16% when it should read 40%…yikes.

Anyway, there are many folks that even do dry hatches where they don't add any water until lockdown with great results. For me, I can add water most of the time because we are so arid here but have done dry hatches in the summer with the incubator in the basement because it's more humid down there. Not sure what your climate is like? I aim for 30-35% humidity during incubation and then try for at least 65% at lockdown.

Normally there is quite a draw down of the size of the air cell during incubation. Have you checked out pictures of what you should be seeing? I would rather see an air cell that is too large rather than one that is too small, in all honesty. The air cell is where the chick pips into first and it needs.some headroom to breathe.

For me, I started weighing all of my eggs prior to setting and writing the number in grams right on the shell and also in my log. For shipped eggs I also candle.the eggs looking for detached or ruptured air cells and draw a.line around the current air cell in pencil. I then reweigh the eggs when I candle at about 10 days. I am aiming for a minimum weight loss of 13% by lockdown and can figure out if I am in track and adjust the humidity if I am not--wanting see around 7-8% at this point. I have successfully hatched eggs with well over 20% loss at lockdown and have had more losses below 10%. For me, weighing works better because the shape of the egg can be deceiving--the pointier eggs will look like they have bigger air cells, rounder eggs smaller ones with the same weight loss.

If you feel that you are having trouble with the humidity being too low, especially at lockdown, I recommend that you put a humidifier in the room where the incubator is. Incubators draw in outside room air so if you start with higher humidity it's much easier to raise the humidity inside the incubator.

I suspect that your problem is the discord between the hygrometers and that is making you over think and fret over the eggies when everything is probably fine! Did you take any photos of your eggs when you candled them? If so you could post them so we can look at the relative size of the air cell with you.

Good luck!

 

[lazy gardener]

No, I don't think you can change the size of the air cell. But, you could increase humidity between now and hatch. Worst case scenario: you will have shrink wrapped chicks, and will have to assist hatch. Much better than them being too wet in the shell and drowning when they pip. I don't know what to say about your elevation and how that will affect humidity and hatch. Have you discussed this issue with any one on your state thread? There should be some folks there with good hatching experience.

 

[micheleomal]

Thanks. Didn't know their were local threads/blogs. Will look now. I will also research assisting shrink wrapped chicks. Very frustrating. I just don't understand how 3 hygrometers can be SO far off.

 

[AmyLynn2374]

If you up the humidity it will slow/stop the eggs from loosing more moisture which will slow/stop the air cells from growing too much bigger. You can't reverse the growth, but if you slow it way down or stop it, then by day 18 they should average out to where they need to be. If you don't up your humidity and slow the moisture loss your air cells will continue to grow and increase the chances of shrink wrapping your eggs. Good luck.

 

[micheleomal]

What should I up the humidity to? 40% or so? The eggs that are only on day 6 still have good looking air cells so I don't want to hurt them in the process of trying to save the rest.

 

[AmyLynn2374]

Anyway, there are many folks that even do dry hatches where they don't add any water until lockdown with great results. For me, I can add water most of the time because we are so arid here but have done dry hatches in the summer with the incubator in the basement because it's more humid down there. Not sure what your climate is like? I aim for 30-35% humidity during incubation and then try for at least 65% at lockdown.

Even (most of) those of us that do dry incubation strive to make sure that we have at least 25% humidity in the bators. If you research dry incubation you will find a number of different quotes to what the "humidity should be" even with dry. The thing is most of us can maintain 20% or more humidity w/o adding water. My last hatch was November, I started using the dry incubation method. I added no water the first 17 days because my hygrometer showed an average of 40% dry. But I also go by my air cells to determine if I need more (or less). I use them as the guideline for my adjustments.

I would go with the 40/45% at this point as you definitely do not want the other eggs to hold in too much moisture. And as soon as you move the first group to the hatching bator I would check the remaining egg's air cells to figure out their needs.

 

[micheleomal]

These are pics of a typical air cell on my 15 day eggs. They were shipped from Florida and have saddle air cells. I read this is typical. The 2 pics are of the same egg turned 90 degrees. I have quite a few with this shaped air cell.



My incubator is a Genesis 1588, has a fan but no auto turner. I am trying the egg carton method. I lean each egg and give a twist several times a day. Temperature: the analog thermometer/hygrometer has been rock steady at 100 degrees the entire time. I don't know if this is actually the correct temperature but since my embryos are developing well, I have to assume it is fairly accurate. The hygrometer on this one read 78% after calibration (salt method in a cool room 63 degrees). I kept this one reading at 40% until I got the one below (small digital)

The small hygrometer is the one that was spot on at 75% in the same room when I calibrated it. This one I purchase online from an avian supply store. The temperature however reads low, about 98.4 instead of 100. I don't think I trust it. As you can see, I have increased the humidity to 42% (the analog reads 60 now)

The genesis hygrometer now reads 50%. I did not calibrate this one. I had a third freestanding hygrometer/thermometer that calibrated at 65% instead of 75% so I just added 10 when reading it. I now have this one in the lockdown incubator, a Hova bator 1602N still air trying to get it ready for Monday. It's thermometer agrees with the analog one so I trust them. I'm keeping it at 100 for lockdown.

I live in high desert. Low humidity usually but we are having a snow meltdown so it's not as dry as usual. I have no idea what the inside humidity is since I don't have 2 hygrometers that read alike. I did think it odd that the analog hygrometer read 42% without adding any water to the plastic wells. However, the small digital read 10% w/o water and that does seem a bit low. I heat with a pellet stove so my air tends to be dry in the house. The room that bators are in is cool but stable at around 63. The brooder boxes are in the same room but have 250W red heat lamps and are ready to go at 95 degrees.

I have looked at pictures of candled air cells and think mine are too big for their "age". As the chick grows can they push out on the membrane separating them from the air cell giving them more room or will it tear blood vessels?

Thank you for your advice and comments. If there are any other questions please ask. I really want to do my best for these chicks. I have 9 (out of originally 23) eggs going into lockdown Monday and another 6 (out of 6) going into lockdown on Wed. The younger ones seem to have better sized air cells so far. I will definitely invest in a scale for my next hatching adventure...

 

[AmyLynn2374]

First just let me say be careful with that Springfield thermometer/hygrometer. I bought the exact one for my very first hatch. I never calibrated it and my first hatch was a fail. After that I decided to check the thermometer against THREE others to find that the thermometer was 6 degrees off! My bator was actually running at about 94F instead of the 99F it was reading. The eggs were developing and very lively, but when I went into lockdown I thought they looked behind, but chalked it up to inexperience. In fact they were behind because of the thermometer. That hygrometer. for me read 40% humidity in the bator w/no water. My thermometer stayed pretty steady at 100-or just before as well, but like I said, it was 6 degrees off w/o me knowing it, so just be careful trusting that one. A forced air is recommended at 99.5, so 99/100 is fine.

I have never delt with saddle shaped cells, but I have heard that it is common w/shipped eggs. They do look a bit big to me, but I don't honestly don't know how to adjust for the difference between saddle cells and a normal air cell. I would probably try to keep the humidity at this point about 40% and see how it plays out. I wish I could help more, but I am unfamiliar with judging saddle shaped air cells.

 

[micheleomal]

Thanks for the heads up about the Springfield hygrometer/thermometer. Mine too reads 40% w/o water even though I calibrated it. Maybe calibrating in a cool 63 degree room was not the right way to do it

. I currently have all three instruments calibrating in a zip lock bag with salt slurry in the lockdown bator at 100 degrees( I think). We will see later tonight what they all read. I will be interested to see what others think of the size of the air cell. I will look for more pics on what the embryos should look like at 18 days and figure out if mine are on track or behind, since I really have no idea now if the temp is truely 100 or 98.4 like the little one reads. I've had 2 other older room thermometers in the bators and one point or another and they are all different temps but since they were old I didn't trust them as much as the new ones (3!!).