RE HUMIDITY IN THE INCUBATOR DURRING INCUBATION.
I Strongly recommend that everyone take the time to read many of the postings in the archives re humidity durring hatching. I have built a few incubators as well as using mfg'd. bators and have had varing degrees of success. I particularly draw everyones attention to postings about maintaining too high humidity durring incubation. When the humidity is too high not enough evaporation occurs to enlarge the airsack properly. The increase in size of the airsac is critical as this is the chicks first breathing air and if its not enough air to get the chick pecked thru to get outside air, it will suffocate before pipping. Another danger of too high humidity can lead to the chick drowning in too much internal fluid. My best results in hatching have been when i kept the humidity no higher than 40% until lockdown at which time i keep it at 70-80%. Once i lockdown i do not open the incubator until day 23, no matter what tempts me otherwise. The reason i do not open the bator durring lockdown is that its almost impossible to regain the high humidity levels of 70-80% fast enough after it drops from opening, to prevent drying and sticking of chicks. If you maintain the correct temps durring incubation and low enough humidity so the airsack enlarges correctly, you have given the chick its best shot, and if it doesn't make it under these circumstances, perhaps its not a strong specimen to begin with. There are ways to save a stuck chick if you encounter one but they are extreme and chancey measures at best that i only practice if it is a chick from a very expensive hatching egg. Anyone wanting this info just ask and ill describe it to you. Btw, its a good idea to set up a tube to deliver additional water for humidity to the bator when you set it up for lockdown so you do not have to open it durring lockdown. I usually use clear plastic fishtank type tube so i can add additional 100 degree temp water from the outside direct to the appropriate resevoir if you see the humidity dropping durring lockdown. Another pointer for anyone interested is that if you use a sponge in your water resevoir make a few "v" shaped cuts into the sponge about 1/2 - 3/4" wide and about 1/2 the depth of the sponge. Remove the material to create "v" grooves that will increase the sponges evaporation surface without having to add more sponges. Happy hatching everyone.
