Well, I have some experience as I was trying to figure out what will be good food for my feeders (try to buy lab blocks here...)
and which kind will be eaten as first so I was giving my mice :
- high protein dog food for puppies (24% protein, no pigments etc.)
- usual dog foor (19% protein, no pigments etc.)
- sunflower seeds
- vegetable treats for rodents
They ALL were eating sunflower seeds, then high protein dog food, then treats. "Normal" dog food was left alone.
Now I stick to high protein dog food w/o pigments and other unnatural ingredients and sunflower seeds as treat. Sometimes vegetables, bread...
So I guess mice eat
1. the fattest thing they can get
2. thing with biggest amount of protein
I bet food you offered to these mice couldn't beat fresly died mouse in this competition... :eats02: That's the way it is.
Once I bought new female to toss some new genes into a pool. I put her with 2 other females and a male -> new colony tha hasn't produced yet. Next day I found only half of this new mouse

uke01:
But rest of this colony are now great breeders, they raise ATM 9 babies and females are pregnant.