Quote:
There is a good question as some bacteria/conditions/diseases can be passed transovarian, meaning that the immunities are passed down. Those immunities are then often considered contagious.
Its a hard call to close a flock when most of us free range or allow our birds out of doors, wild birds spread a lot of conditions and their droppings, dust or that stuff is how a lot of these conditions to cross species.
You know, this is a difficult subject as we hear how closed people are- well closed flocks, yet if you want to better your birds, show them, raise more, I would suggest finding NPIP tested birds to lay those eggs.
I would have to say you do not have a closed flock if you are bringing eggs in, yet technically they are in quarentine during their first 19 weeks of life, so if you was to come up with a problem, the chick would die or show weakness- right?