New Delhi, July 22 -- My dog has always been a fussy eater." It is one of the most common sentences I hear in the consulting room. Sometimes that is true. Some pets genuinely have strong food preferences. But more often, a change in appetite is one of the earliest signs that something else is wrong.

A recent patient, an eight-year-old Golden Retriever, had become selective with his meals over months. His family had tried everything and were convinced they simply had a fussy dog. An oral examination revealed the real problem: a painful fractured tooth and advanced dental disease.

Pets are remarkably good at adapting to pain. They rarely stop eating overnight. Instead, they eat slowly, leave food behind, chew on one side, avoid hard kibbl...