Brokenangelr,

Rats are better nutritionally than mice as they have more protein and better muscle mass. Besides, mice will eventually be too small to be a sufficient meal without feeding multiple animals in one feeding. Sounds like if she took a rat, all is good. Just use the rats you have smallest to largest. A good rule of thumb is to make sure that the diameter of the rat is not much larger than the largest diameter of the snake. If it is, you'll want to save it for another feeding later when the snake is larger.