I think BO or B.O. rather,means body odor
Mine get a variety of proteins, chicken n apple meatballs, headless super worms ( they bite ), eggs, chicken, turkey, salmon( their fav!), shrimp(now n then), veg and egg "pancakes" even a clam once in a while.
Even though I give them a pretty wide range of proteins it is not an every day thing. . The protein is not a huge portion compared to their regular meal,they also get their normal staple and vegs/fruits with it.
I also remember reading somewhere if they ate a high protein diet their odor or scent may become stronger but I think those portions were bigger and an everyday thing.
I've never noticed a difference in my critters smell.