Sorry if this is posted on the wrong spot, I wasn't sure where else to put it!

I've noticed Naga will only eat mice if their guts are hanging out. (I just got him about a month ago, he's always been on FT mice)
Is this normal or just my little guy being silly? Whenever I've offered mice without a horrible smell and guts out, he's not at all interested and would rather just explore.
I don't mind it, I just think it's funny and was wondering if anybody else has experienced it!