Quarantining a new bird?

I am seriously considering buying one or two hens to add to my two young pullets. ( mine are 14 weeks,hers are 10 months)

I can tell the woman I am buying them from doesnt think its an issue, becuz she said I dont need to quarantine and its best to just throw them in with my birds right off the bat to establish pecking order. uhhh...well ok, I will just nod and NOT do what she says of course....my two are MY babies and I am not risking them getting sick or pecked.

My question is, to quarantine, how far do they have to be kept from my babies to make sure they are not sick, can they be kept in a pen close so they can see each other or would they still be at risk that way, or should I keep them for a few days (how long?) totally (like not even within vision range?) away from my birds?
TIA
Jill

Since no one has answered you yet, I'll tell you what we do.

First take a good look at her chickens. Look for any gasping, rough looking feathers, droopy looking birds, look at their poop.
Touch some of her birds. A healthy chickens feathers feel silky. Check for mites & lice.

If you decide to get a couple, keep them totally separate for at least 1 month.
During this time, observe them closely. I usually give them electrolytes for 3 days, then observe. If there poop looks a little off, I will worm them. I try not to medicate them, so as not to mask any illness that may be passed on to my chickens.
If you can, get them on the ground, not in a cage. There may be different elements in your soil compared to where they have been, that they have no immunity to, I mix some medicated chick starter in their feed or give them Corid in their water if they show signs of coccidiosis.

VERY IMPORTANT!!! Always tend to these chickens last.
Then wash with peroxide or a sanitizing soap.
You do not want to carry anything from them to your healthy chickens.

After that time period & there is no problems, you can put them in a cage or in a pen next to your chickens so they can get acquainted through the wire without any injury. You will have to observe them as to when you think they will OK together. When you put them together, do it at night. Place them on a roost, so they wake up together in the morning, & be out there early to observe them. There will be some pecking order squabbles, but they should not injure each other.

Sorry this was so long, & I hope I didn't forget anything. Maybe someone else will read this & have additional tips for you.

Hope this helps.

Jean

All I can think to add is to find out what type of feed the birds are accustomed to so if there are any changes due to their diet, you won't confuse them with symptoms of illness.

I say this because I did get birds some time back from a man that I later found out only ever fed the birds cracked corn. Their poo looked a bit off for awhile until they got used to layer pellets/grit/oyster shell, that they had never even seen, much less eaten before.

Otherwise, Jean seems to have covered everything very well.

I have only done this one time and it was stressful. I bought one rooster who was kept in, to me, substandard conditions. He was in quarantine totally away from the entire flock in my bsmt bathroom in a dog kennel or on the deck up over the heads of everyone in another kennel. He had a bath, was wormed, checked for breathing problems. He did breathe weird, but that was just him. At one time or another, I thought he had aspergillis or canker, but thank goodness he had neither. I did find he had lice, something I've never had on my Girls, so he got dusted with DE and I put it in his bedding. He got decent feed for the first time in his 10 months of life, too. It was stressful that whole time; I was thinking, what have I done? Anyway, he was fine, but I am glad I kept him away from my precious flock that entire time. I'll never buy another grown bird again probably, LOL. He's a great flock rooster now.