Hmmmm. Not sure. Dogs get excited. Dogs get scared. Dogs get angry/defensive....
Dogs have personalities for sure. The question is, are their emotions connected to their thoughts. A dog will never feel bad about biting someone. But they may feel bad about upsetting an owner who has trained them otherwise. A potty trained dog will hide when it has an accident in the house. It remembers that the last time this happened a certain nose got rubbed on the carpet. Their behavior could be connected to what they expect will happen. They are reminded because the smell is still in the house. So the behavior goes on for extended periods of time. But what about when my dog whines and cries when the kids are out playing and she can't go out. What about the excitement they show for a car ride? If someone asks my dog if she wants to go for a ride, she'll go nuts for a VERY long time until you at least put her in the car and drive around the court. Then she's satisfied. She doesn't care for how long it is.
I have seen "spontaneous" emotion and looked for links to training or conditioning. I watch for the difference because it fascinates me and my dog does some amazing things now and then.
“They don’t have emotions”
I am convinced that they do. My wife says that when I leave town, the dogs mope about for two days. They are deliriously happy when I return. The female dog is insanely jealous when I pet the male dog; she barges in between us and demands to be petted stead. If I am not feeling well, the female puts on the saddest face and tries to snuggle with me.
Of course dogs have emotions. Their brains have the same parts ours do, and the parts if their brains that process emotions are structurally and biochemically the same as ours. Hence, they feel rage, grief, joy, jealousy, etc. just as we do.
The difference between dogs and humans—at least, some humans—is that we have a far more highly developed cortex, particularly in he prefrontal area. This is the part of the brain that (we hope!) imposes some control and direction and rationality over the animal emotions and desires we mammals all have in common.
Thus, acknowledging that dogs have emotions doesn’t put them up on the same level as humans or invest them with the same value as human beings.