The useful question is not whether a dog eats breakfast. It is whether this is how it has always been.
The pattern that is not a problem
Many dogs are simply not hungry first thing, particularly if they had a substantial evening meal ten or twelve hours earlier and have not yet been exercised. They leave breakfast, eat it later in the morning, or eat well at dinner and make up the total across the day.
If a dog has behaved this way for months, maintains its weight, has good energy and eats enthusiastically at other times, this is a preference rather than a symptom. The practical response is to feed it in a way that suits it — a smaller breakfast and a larger dinner, or a single daily meal at whatever time it eats reliably.
Two things are worth adjusting alongside that. Walk before feeding rather than after, since exercise stimulates appetite in most dogs and it is also the safer order for deep-chested breeds. And lift the bowl after twenty minutes rather than leaving it down, because food that is always available stops being an event.
The pattern that is worth attention
A dog that used to eat breakfast reliably and has stopped is describing a change, and changes in a previously consistent eater are worth taking seriously even when everything else seems normal.
The things to look for alongside it are the usual list: energy level, drinking, vomiting, stool consistency, weight, and whether it is eating well at other times of day. A dog that has stopped eating breakfast and is eating less at dinner is not a dog with a morning preference.
The bile pattern
A recognisable version of this involves vomiting yellow foam in the early morning, followed by refusing breakfast, and then eating normally later.
The usual explanation is a long overnight gap with an empty stomach, and bile irritating the lining. It often responds to a small late-evening meal or a snack before bed, which shortens the fast, and to splitting the daily food into three portions rather than two.
It is worth mentioning to a vet if it happens regularly, because other conditions can produce the same picture. But in a well dog with good weight and energy it is common and manageable.
Mouth pain shows up at breakfast first
Dental problems produce a distinctive version. The dog approaches the bowl with interest, starts to eat, and then stops or drops food. It may take soft food or treats but leave kibble, or chew consistently on one side.
That belongs with a vet rather than with a change of feeding schedule, and it is one of the more commonly missed causes of a dog going off its food gradually.
Ruling out the simple things
Before concluding anything, check the food itself. Kibble goes stale and its fats go rancid, particularly in a bag that has been open for weeks in a warm room, and dogs detect that long before people do. Try a fresh bag or a sealed portion from a new one.
Then check the total intake including treats, chews and anything given during training. A dog that is not hungry at breakfast is quite often a dog that had a substantial amount of food between dinner and bedtime that nobody counted.
Weather and season change appetite more than people expect
Dogs eat noticeably less in hot weather, and the drop is usually most obvious at whichever meal falls in the warmer part of the day. In summer that is often breakfast for households that walk in the evening, and it reverses in winter.
Activity level moves with the season too. A dog getting an hour less exercise a day through a wet January is genuinely less hungry, and adjusting the amount down for a few months is more sensible than trying to persuade it to eat a summer portion.
Both of those produce a gradual, seasonal pattern rather than a sudden change, which is the distinction that matters. A slow drift over weeks that reverses when conditions change is normal. A drop over two days is not.
Deciding whether to change anything
If the dog is holding its weight, has good energy, and eats well at some point in the day, the honest answer is usually to leave it alone and feed at the time it prefers. Two meals a day is a human convention rather than a canine requirement, and plenty of adult dogs do perfectly well on one.
The reason to intervene is a change in weight or condition, not a change in the schedule you had in mind.