Stress can be triggered in a dog by change in environment or the need to react concerning a change in the environment. It may be the chronic lack of certainty concerning its daily routine. It does not need to be dire or life threatening to create stress. Pets are sensitive to their surroundings and form emotional bonding with their owners as well as other family pets (Symptoms 1). Any "change" can create stress in a dog. Bites from another animal, broken bones, travel, breeding, showing, or accustomed affection can cause stress in a beloved pet. Stress is a signal for the dog's internal system to react and may cause rapid heartbeat and increased breathing. Any health problem may cause stress in a dog. This is true whether the health change is in the dog's health or the owner's. The animal may show stress by anxiety, fear, or restlessness. The dog may seem to be listless or act withdrawn. Life is filled with inconsistency for humans; it is likely that a dog will experience stress sometime. Constant stress can lower a dog's immune system or cause behavior problems.