My dog did this to me... drove me crazy! One day she wouldn't eat no matter what I did(wet food, water on her food, not even treats!), the next she ate almost normally.
I think the pain is what might be causing this.
Like another poster said crumble up the food and add a little water, this helped my pup eat better, in fact she would gobble it down.
Good luck! If you notice any dramatic changes as he's not full of energy or not drinking water or going to the bathroom, I'd take him to the vet.
__________________ Rachel and  Mahina |