I have a Rhodesian/Lab he's 13 months. I did the mistake mixing some table food with his dry food. Now he won't touch anything regardless of what I put in front of him. He snubs it. He's not lethargic, he's very active, his bowels are normal, he drinks plenty. How do correct this? Or should he see a vet for a hidden problem that I'm not aware of? Thanks for you help!