Any additional input or encouragement

[EveCh]

So there are about 1000 posts on incubating but here goes sorry a little long and rambling: I've incubated a couple times over the years without much success. I usually use my hens with great luck however some years I get no broodies, others (last year) I get half my flock (annoying!). One of my boys is all about chickens, I'm not disappointed I love my birds. At 4 he collects the eggs, feeds etc. without prompt everyday. I like to encourage interests in my kids especially when it has a function (not video games!). He (I won't lie me too) has been wanting some chicks. I have a good friend with lavender orpingtons (which are gorgeous) that is willing to basically give me eggs (fertile or at least a roo is running with the hens). However, before I ruin 'special' eggs I'm practicing on my hearty barnyard mix. I typically get above 90% hatch rates with hens so I know my eggs are good to go. I have an older round hovabater no turner, 2 digital thermometers that I've calibrated and a digital hydrometer. First hatch is on day 22 and it's not great. 2 hatched on day 19 and 2 on day 20. All were slow and have a few 'issues'. Another 2 fully formed pipped, one half-way zipped another just pipped both died. I will give it another day or so then eggtopsy but candling (dark eggs so only rudimentary idea) shows air sacks and development in all of them. Air sacks seem small but I didn't chart it so really that's just a guess. Temp was rock solid at 100-102 on top (that thermometer is super sensitive) and 97 on floor (this thermometer takes a reading every 10 sec so not as spacey), humidity was pretty solid at 40-55 for 1st 18 days, 65-75 at lockdown. So I know my temp was to high and it would seem my humidity as well. I'm going to scrub down my bator and reset it at 99-101 (again it bounces but the other won't stay on 'top' well). I'm also going to do a 'dry' hatch ie. add water to well on day 1 and just record it until day 18 and aim for anything over say 20-25% then add water for lockdown. I should see better results. Anything else? I'm also going to put something over the wire floor. When the couple hatched they were playing ping-pong with the other eggs in there. I don't think that did them any favors. As well as I'm not convinced catching toes in the wire didn't contribute to this one's foot issue. I have shelf liner but it's rubber/plastic is that going to off-gas or ?? Or paper towels or old tee-shirt material? Anyway, that's my rambling project of late.

 

[ChickenCanoe]

In a still air, I use that rubber shelf liner over the screen. It works great.
Even before I read the temperature, I could tell you your temperature was too high throughout. Hatching on day 19 and 20 tells me that.
Temps may seem to bounce but it doesn't affect the internal egg temperature as much as you may think. Different thermometers have different response times. I have a couple instant read thermometers and they fly all over the place because when the heat element kicks on, the temp will climb dramatically and then slowly back off. I use the temp reading right when the heat element kicks on to determine internal egg temp.

 

[lazy gardener]

Hatch temp should be read at surface of eggs in still air and should be 102 according to "hatching eggs 101" in the learning center. My last hatch, I had stability problems b/c of sketchy air circulation with my fan, so I turned the fan off at mid way point, jacked temp to 102 at egg surface and had a great hatch. You may also have issues with your humidity and air cells. That you had developmental issues says there was a problem with either your temp or your breeder nutrition.

How did you calibrate your thermometers? I calibrate to 100* in a cup of warm water using a quality medical grade thermometer as my gold standard. While "they say" to calibrate to 32* using ice water, that does not make a lot of sense to me. If a thermometer is accurate at 32*, that does not necessarily mean that it will be accurate at 100*, where accuracy counts!

I also think you may be using too much humidity. Humidity is a tool which you use to ensure that your air cells are the right size at hatch. If your air cells are too small, the chick may drown when she pips into the air cell, b/c there is still too much albumen in the egg. My goal is 30 - 40% until lock down. At times, I need to run completely dry right up until first internal pip to ensure that air cells are correctly sized.

If you have not yet done so, Please read ALL of "hatching eggs 101" in the learning center. Much information there that will answer questions you didn't even know you had.

 

[EveCh]

1. Read hatching 101 and just about every blog on internet or so it seems
2. Calibrated at 100 with a medical thermometer, the one on top reads about every second so bouncing is expected, I was trying to hit that 101 mark so 100-102 bounce every other second should have been the right range. Reasonably sure my temps are what is being reported. But the early hatch says for my particular set-up my yolk temps were too high even if hatching 101 etc. says otherwise! I'm dropping it a degree next time.
3. I think humidity played the largest part in my fail. While I am in the range based on articles etc.; these are recommendations and why experience and good records is sometimes the best teacher.
3. Flock health, while important and something I'm glad you mentioned, is not an issue in this case. I am more sure of my eggs than my friends, hence experimenting with my own to get the other variables correct.
4. Good to know on the shelf-liner.
Thanks for the responses.