It takes about 25 hours for an egg to go through the hen's internal egg making factory. It can only be fertilized during the first 15 minutes if that journey. This means if a mating occurs on a Monday, Monday's egg is not fertile. It started its journey the day before. Tuesday's egg might be fertile or it might not., It depends on what time the mating took place and when the egg started its journey. Wednesday's egg will almost certainly be fertile. This is after a mating, not after an introduction. A rooster does not necessarily mate with each hen every day. It just seems that way. You might want to look through this thread. It shows you what to look for. If you can't see the bull's eye, you might have to gently turn the yolk over. I use a spoon. If most of the eggs you crack are fertile, then you can assume most of the others are fertile. Fertile Egg Photos https://www.backyardchickens.com/forum/viewtopic.php?id=16008&p=6
Thank You! I have a little Buckeye Bantam hen that wants to set but I rehomed my Roo in March. My neighbor gave me some of his eggs for her to have and I think he's had his Rooster for over a month so surely those eggs are fertile and she will hatch them out!
