Close-up of an aggressive dog snarling and baring sharp teeth, showing tense facial expression and open mouth in a neutral indoor setting, conveying warning and defensive behavior.

dog canine pet animal teeth snarl snarling aggressive angry growl bark warning threat defense feral fierce menacing attack biting jaw muzzle fur closeup portrait expression emotion intense alert danger unsafe hostile guard protective mouth tongue sharp dental saliva indoors collar petcare behavior caution stress tension focus white brown