How are animals that eat only one kind of food not horribly malnourished? Do they need a narrower set of nutrients than humans?

Question

How are animals that eat only one kind of food not horribly malnourished? Do they need a narrower set of nutrients than humans?

In:

Answer 1

Different animals are able to digest different things and have different nutritional requirements. Example is dogs and cats. You can’t give a cat just dog food because it lacks an amino acid that dogs produce on their own but cats need through their diet. But you can’t give a dog just cat food because it’s too high protein.