How long does a disease in chickens take to show?

[texas hiker]

In a previous thread I talked about how my wife and I adopted a rooster - https://www.backyardchickens.com/t/826221/anyone-rescue-a-rooster-from-a-bad-home

We skipped a quarantine period, and we are now at 8 days with no sign is illness.

How many more days until we will be sure the flock and the new rooster are disease free?

 

[Wyandottes7]

It depends on the disease. Some diseases take only a few hours, while others won't appear for a couple weeks. By the time you've had him for three weeks or so, you can be reasonably sure that he doesn't have a disease. However, some diseases, like Chronic Respiratory Disease, are not always apparent. The bird remains a carrier, only showing symptoms during times of stress.