I have a 2.5 year old staffy  bitch who has just had her 1st litter they are now a week old. She was feeding them very well, but the last couple of days has taken a dislike to a particular pup and although she hasnt bit him she has growled at him on a number of occasions she has done this to another pup as well.
She only wants to get into the whelping box for a few minutes at a time and has taken to sleeping in the hallway cupboard away from them. Has anybody some advice please?

I would ask the vet to check her over, she may be in some discomfort if she's been feeding OK and now isn't too keen.

Yep she may have mastitituos or the pups nails could be to long, check her teats for any heat or hard swellings, also get the vet to check her.

Warm regards Susan

I would agree with the others that she may be in some discomfort. I would also make sure the pups are supervised when the bitch is with them.
Best of Luck
Jodi

Check nails, breasts and make sure she is getting enough calcium.

You got there before me Blue, I was about to say get the vet to check her calcium levels!