It could be a difference in the size prey items they are able to eat. With live rodents, you're often able to get slightly larger prey items for the same price, or there is more variability in size of prey items period because they are not euthanized when they reach a specific gram weight. So as a result, you may be unintentionally feeding slightly larger prey items, which is resulting in a growth spurt.

That's what I noticed anyway with frozen vs. live for me - our frozens are all nice and uniform, while the live can and often are slightly larger than the similarly labeled frozen.

Otherwise, there *should* be no noticeable difference in nutritional value between live or frozen rodents.

-Jen