Respectfully, It is written about the capability of the the bp and larger constrictors including retics, anacondas digestive system being made to handle one appropriate sized meal over many inappropriately sized ones. The differences cant be meaningless when the op question was which is better. Of course there are studies showing the requirements of bp's and most are inclusive of classes of reptiles and are weight based. When you compare mice to rats gram for gram there are nutritional differences and the rat is above the mouse. The ash percentage is better over mice bc a low ash content can be harmful and deprive an animal of essential minerals like calcium and manganese. I know bp's can thrive on mice but would you agree a bp on mice for its life is going to be a lot smaller than a bp raised on rats? This is just the little research I have found. Everyone can choose what they want to feed their animals, I am just putting a IMO out here for people to see. Thanks...Bp's who are on mice can be and should be transitioned over to rats as a process. It can be done , I've done it and most people should do it.