To rancher Hicks: Thanks for your info. I have 2 of the 3 brand new incubators from Cornell Coop Ext. Although the temp tested 100 when I had it running for 1 1/2 days, after the eggs got in they seem to hold a steady 101. I opened the vent hold but don't want to mess too much now that they are going. I checked it with 2 different thermometers and they both run about 100.9-101.1 I'm a little nervous about it but I read that that it is still in the ball park of acceptability. My bator ran closer to 99.6-100 last year but hatches were almost a day later and hatch was not good. I can;'t do this!! I worry too much!!! If it were just me I wouldn't care, but I don't want to disappoint the 5-6 year olds who are waiting patiently.
K.......
I was told by Don Schrider of the ALBC that if you use two thermometers to take the average of the two and go with that. He also said to follow the manufacturers instruction as closely as possible.
I have the Gen. 1588 and I think that different areas of the incubator are not exact to the temp. I believe this because some of my hatches start early and finish late. This last hatch started on the 23rd (Feb) and finished on the 25th. To be honest the last egg was one that was put in a day after all the rest. The 21st day would have been on fri the 24th. My point being I don't care when they hatch as long as they do. I've learned to be patient and give those last eggs a fighting chance of a day at least. I wait the three days the first chick has before it needs food and water and only after that do I open the incubator and snatch the chicks. I close it back up and leave it to finish.
I do not believe that opening the incubator causes "shrink wrap" The science is just not there. I have had broody hens with shrink wrapped chicks. There are in fact holes in the bottom of my incubator and of course the vent hole in the top. These are necessary for the eggs to breath. Otherwise the incubator would become full of carbon dioxide as the embryos exhale. I haven't studied it but that's my opinion. I believe there is some other reason for shrink wrapped chicks. Perhaps the membrane is to thick and the chick can't break through it. I've noticed when I crack open some eggs this membrane is thicker than others.
I do think opening the incubator to much can create problems. Though I open it and turn each egg a quarter turn for the first three or four days. I know hens rotate their eggs and don't simply rock them back and forth. I've read that they actually move the outer eggs to the middle and the middle eggs to the outside of the group. We don't do that in incubators, thereby leaving the eggs either in a cooler spot or warmer spot of the incubator.
Sorry I said to much again.
Rancher