First off, this isn't the place to discuss breeding feeder mice or rats. Try this location:
Feeder Forum
Second, what is your setup like? How old are the mice and how do you cage them? What size of cage and how many mice per cage? Where is the cage located and what is the temp? Where did you get the mice to begin with.
Rats are slow to settle in to breed. If too young, they tend not to breed right away (oh the male goes through all the motions but no litters are produced for the most part) If they are to old, the females may never litter or only litter once or twice. If the age is right and no new ch anges are made, typically they should produce in 3 months or so. Give the same info about the rat set up as well. (or read back posts in the feeder forum, there have been alot of threads about breeding mice and rats). Also, food doens't have to be expensive lab blocks, any cheap dogfood with at least 14% or higher protein content and about 8% or higher fat, with no perservatives or dyes, can be used instead. Though with dogfood I would also add in mixed seeds, fresh greens/fruit (toss in some of the same food you give your dragon, including insects, a couple times a week).
On a side note, dragons don't need to be fed mice at all. Some breeders feed pinky mice to female dragons after clutching to help get weight back, since dragons multi-clutch. If ot a breeding female, you can skip mice completely.
-----
PHLdyPayne