Trying to calculate when eggs fertile by correct rooster!?!?

Eggs can be fertile for up to 4 weeks after breeding. Three weeks is the usual amount of time people give before collecting eggs for incubation after removing a roo that's not wanted for breeding.

I figure 10 days after the roo is gone it's a good bet that most/all the eggs are fertile. It's three weeks after the old roo is gone if I want to make sure the chicks only have one daddy though.

You can also seperate the hens completely and bring in the desired roo after the eggs have been clear for a few days--no bullseye when you crack them open. I like this method when possible because many hens won't stay fertile for three week from the last breeding and by checking the eggs for fertility I can often get started after two weeks instead of the full three. There can be problems with the hens not wanting to accept the roo when you do put him in with them so if you have a young roo and older hens this might not be the best method for you.

 

Give it at least 3 weeks. Unless you're hatching for you and don't care if you get some mutts.

 

I wait at least 3 weeks when switching roos.

 

I agree with the rest on how long they stay fertile. Let me attack the other question. In your situation, this is obviously not a problem.

It takes an egg about 25 hours to go through the hen's internal egg-making factory. The egg can be fertilized only in the first 15 minutes or so of this process.

If a mating occurs on Monday, Monday's egg will not be fertile. That 15 minute opportunity passed the day before. If the egg starts its 25 hour journey after the mating occurs, then there is a possibility that Tuesday's egg will be fertile, but there is also the possibility that it will not be fertile. Wednesday''s egg will almost certainly be fertile. Note that this is after a mating, not just after they are put together. A rooster does not necessarily mate with each and every hen every day.