some advice about pups

[Fisher]

I am fairly new to gerbils and brand new to gerbil pups.  Can someone tell me how long and how often the pups are supposed to nurse in different stages of their development?  My Pretty's 3 babies are 3 days old now and I was wondering if they are nursing enough and for long enough. This is her first litter.   Thanks in advance for any answers.   Sara Fisher Baltimore, MD