I know nothing about this level of discussion around pet food so I have nothing to add but I'll share a related story about cat food and feline communication.
One of my wife's now deceased cats was on store bought cat food and we decided to upgrade him to a better food as we were told the old may be contributing to his urinary tract infection. The cat went a couple of days without eating a thing. I figured, 'Pfftt, if he gets hungry enough, he will eat it.
On day three, we returned home to work to discover that he had crapped in his food dish. He had never missed his litter box before and it would have been a bit of an effort for him to pull this off as the dish was on a raised wooden platform in the shape of a cat that her brother had made for my wife as a gift. He would have had to maneuver his rear end up onto this platform and ... well, you already know the rest.
People say animals don't truly communicate? I say they do just fine.
Cats are def more of a challenge when it comes to being picky eaters. Not we haven't met a few dogs that are like this. We usually recommend mixing food for at least a week, and sometimes two weeks. It's not uncommon for a pet owner to switch cold turkey and the pet doesn't react favorably. Then they think the new better food is no good, they get frustrated and then go back to the old stuff.
