
I was told years ago by my mentors to not rely on the scales but on how the pups feel,a nd behave. You want firm feeling pups who are content. Trouble is when you bred your first few litters you don't know how the pups should look, feel and sound, so only have the scales, and end up worrying. That said the scales are invaluable for helping to spot trouble early, so that you watch a particular pup, giving it extra space at the milk-bar etc.
I have to admit I weigh all my pups but it is amazing how much difference there is in weights of pups depending on how fast the bitches milk comes in, how many pups there are etc, yet by about 12 weeks all pups weigh about the same with boys a pound or two more.
Eventual adult size is not Dependant on how they did (unless of course a pup was malnourished) as babies.
My Lexi and her 3 litter mates put on huge amounts in their first weeks, yet she is no bigger or better boned than ones who gained a lot less.