I thought it somewhat amusing when traveling back from Japan with a dog that the dog is what generated the "X" on my GE slip (obviously I answered "yes" to the "animals" question). But the customs agents didn't care at all about my dog, didn't ask for her paperwork or anything. It was, "Do you have any dog food?"

The first agent wanted to confiscate the sealed bag of dry dog food in my checked bag. His supervisor (who he requested to confirm) just shook his head and said, "That's fine. It doesn't count as meat."