To update, there was no reoccurrence of this behavior the rest of the day or this morning. So that’s good.
To clarify, he performed the bow after his first bite of breakfast. Took a bite, spit it out, looked at his food dish as if he had been burned by too hot food (his food comes out of the fridge), walked 3 steps away, bowed, held it for one-one-thousand, returned to food bowl, tentatively tried a bite, seemed fine, ate a few more bites, stopped, bowed, one-one-thousand, returned to bowl --before I could take it away–, and finished. Then went to living room and bowed for several one-one-thousand seconds. The stood up, went to his bed for after breakfast nap and everything has been normal since then, including 2 meals.
So I’m thinking though not megaesophagus but something with the esophagus because it first happened with the first bite of food. As if he was burned, so whatever it was hit him when he went to swallow, as a burn would be felt if you were eating fast (as a dog does). I’ve had a dog with pancreatitis and that does affect appetite at the food bowl but an acute bout would be felt during primary digestion phase, not upon swallowing. At least this is my thinking.
But then he’s always horking up a potato chip that he tried to swallow whole and he didn’t attempt to do that at all so clearly the food was allowed to pass so maybe never mind.
So yeah, bowing would indicate upper stomach pain. You wouldn’t expect to a dog to bow with throat pain–would you? It was just so very odd.