Hello all you clever people!
I've read so much on this forum about humidity, candling, embryo development, etc. And it's been exciting putting my first ever chicken eggs into the Brinsea incubator.
One thing I don't know is: What day is day 21? It was a Thursday evening when I set 7 eggs, and after 14 days only 1 wasn't developing. Sunday night the eggs started to jiggle and the automatic turner stopped on Monday. I topped up the water pots, took out the turning disc, put in a rubbery shelf liner and am in lockdown with the 6 developing eggs.
Now, however I'm wondering whether the Brinsea may have been set incorrectly and should day 21 be Thursday? Lockdown Monday lunch-time feels too soon.
Should 21 days mean: set eggs Thursday, likely hatch Thursday?
I count the day I set the eggs as day zero. The next day at that same time is day 1. With that being said, incubation temperature will affect hatch day, if the temp is a little low...say 98 degrees the embryo will grow slower than if the temp was optimal for your type of incubator. A slightly higher than optimal temp may result in a day early hatch. Good luck with your hatch and be sure to let us know how it goes!