How much will 9 day old puppy eat at one time?

Question
Had to take 3 puppies that was 6 days old, away from mom.  The mom before she was pregnant would chase her tail at times for no apparent reason.  Well she had a litter of 5 pups one died at birth. One runt later died also, they were both solid white.  Was putting feed into mom's dog house to feed her , when out of nowhere she started chasing tail, which was no good because she was over the 3 puppies in the process of this tail chasing!!!  She cut the female white one enough there was blood.  Of course when she saw what she had did, she started cleaning and whining about the pup that was cut.  Then my husband come home to check on the pups , because she started this chasing of her tail whenever me or my son even got near the pen.  So that is why I called my husband in to check things out.  By the time he had got home to check on them.  She had the white one that had the cut on it outside the doghouse and had dug in the dirt, but was back inside doghouse with the other two boys.  When my husband went to check on the white one it was still alive , so we decided we should get the others away too, because one had been cut on the leg too!  So we called the vet to see what to get to start the feeding ourselves.  So now we are doing only bottle feeding!  The only thing is there are 3 of them and I am usually the only one that is up during the night feedings.  I try to switch them out and feed each one until they lose interest in eating!  Of course do the burping thing and also try to do the moist wipe after feeding to make it feel as though mom is still around!  The only thing now they are getting where they don't want to eat for my son and husband only myself!  Is this common do they think I am mom now or what?  I am going to purchase a food scale to start weighing them to make sure they are eating enough.  But they all are peeing and pooping good though!  Just want to be reinsured I am doing all I can for them.  Also is it ok to let them sleep even though it is a little past the 2 hour feeding time?  
Thanks
Rachel

Answer
Hi Rachel,

I'm glad you intervened and saved the puppies. It sounds like the mother was very stressed and not handling things well. They don't realize they can hurt their babies by being too rough. It would have been best to have them all in a place (like a plastic baby pool) inside the house so you could constantly keep an eye on them. Inside of a dog house was not the best place because you weren't able to see them at all times. You were smart to call the vet and start feeding them yourselves, but if there is any way that you can get them back on the mother (AND WATCH THEM CONSTANTLY) then you should. Nothing is better than mothers milk.
The puppies have associated your smell with feeding - so they probably feed better with you than your son or husband, but if they are hungry enough, they should eat no matter who is feeding them.
Yes, it's OK to let them sleep A LITTLE past the two hour feeding time but not too much more; keep weighing them and make sure they are growing and gaining weight. They will stop eating when they are full, so feed until they stop sucking. You're doing a good job, I know how hard it is taking care of orphaned pups., it's an enormous job!
Best of luck and continued success!!!