Dog dreams symbolize loyal friends and interpersonal relationships. A cute, healthy puppy means a new friend or good connection is coming. A barking dog signals danger or a warning. Being bitten by a dog warns of possible betrayal from a trusted person. Petting a dog means good relationships are maintained.
Animals appearing in dreams — as in "Dog Dream" — often symbolize instinct or a suppressed impulse in Jung's theory of Archetypes. The specific animal and the emotion it evokes in you both shape the meaning far more than a generic dream dictionary entry can.
What was the first emotion you felt when you saw that animal in the dream?