rescued JRT mom and puppies

Question
Hi Carol,
I am fostering a rough coat Jack Russell Terrier mom and her two puppies.  This is our first experience with JRT's, so quite an eye opener.  We typically foster large breed dogs, as we have a Scottish Deerhound, two Golden Retrievers and a Golden/Corgi mix.  

Anyway - all is well, "Foxy" and her puppies came to us when the pups were 2-3 days old, they are 6 weeks old now and doing well - everyone is healthy and thriving.  Pups weights yesterday were 3.7 and 3.8 lbs.  Foxy started weaning about a week ago, so I introduced milk replacer and puppy food mush which they took to well, they now are eating mostly dry kibble - with a little wet food added on occasion.  I leave them in their x-pen without Mom several times a day for an hour or two and they do fine - whine a bit, but get busy wrestling with each other, or chewing on a toy or bone and settle nicely. Mom is happy to be away from them and hang with us or our dogs.  She LOVES taking walks twice a day and spending time in our yard with our dogs and us, so doesn't seem overly anxious to get back with them.  She really likes to sit in a lap or lay on the couch and watch TV in the evenings.  When the puppies are loose in our kitchen and breakfast room (with wood floors), she'll play with them and reprimand them firmly if they get out of hand.  One puppy in particular challenges her authority, where the other seems much more subservient and "gets it" when she corrects him.  She is content to let our dogs play with the puppies too - and enjoys just laying on a dog bed with a nylabone and watch the other dogs with her puppies.  My question is this:  How often should I separate them from Mom and for how long?  The other night she went into her crate alone and got a little anxious and tried to get out of her crate when I put the puppies in with her, so I put them back in their x-pen and left them separated for about 6 hours. Mom in her crate and pups in their x-pen.  Was that too long?  All was fine in the morning, but I don't want to jeopardize the pups development by keeping them from Mom for too much time too soon.  Any advise would be appreciated.   

I don't plan on placing them until they are about 10 weeks and can be neutered first.  Mom won't be placed until after she's spayed - at least a month or more from now, I would think.

Thanks for any advice.
Karen,  

Answer
Hi Karen,

Thank you for writing, and thank you for being such a special and loving person and taking care of this new little family.
You're doing such a great job and I loved reading about the puppies.
You will find different opinions on when to start separating puppies from their moms but it has been my experience that the 7 week period works best. I usually start with a couple of hours during the day, mainly to give Mom a break and to keep those little teeth off her nipples(exactly what you're doing).  At night, what I have found works is to keep them in a large x-pen together (or gated in the kitchen) but with separate beds, one for the puppies to snuggle together and one for Mom. Have the beds JUST fit, not too much extra room in either of them. That way, she can move back and forth away from them when she needs to, but still have them "available" if she needs to go over and check on them. Lengthen the time that she is not with them by about a half hour a day. You have time, especially if they are staying for 10 weeks. By week 9 they should be completely separated from eachother except for playtime during the day if Mom wants to. I'm sure by this time, Mom won't let them near her nipples whatsoever.
You're a pro and doing great, keep up the amazing work.