Why is My Dog/Cat Aggressive?

In dogs and cats, aggression refers to aggressive behavior towards conspecifics or towards humans, stemming from various causes. In some cases, especially in dogs, aggressive behavior is also directed against objects.

As a rule, aggressive behavior in dogs and cats is not a disease; rather, the behavior lies within the normal behavioral spectrum of the animal species. These forms of Aggressiveness usually develop gradually, are sometimes linked to sexual maturity, and/or develop through learning. They can be influenced by training.

In rare cases, organic causes can also be responsible for aggressive behavior. These forms of Aggressiveness can only be influenced by eliminating the causes.

Aggressiveness within the Normal Behavioral Spectrum of the Animal Species

• Dominant behavior (hierarchy position)
• Defense of a sexual partner
• Defense of one’s own territory
• Defense of one’s own pack
• Defense of specific objects
• Aggressiveness due to Uncertainty / disorientation
• Aggressiveness as a result of Pain
• Aggressiveness due to stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being. (cats)

Aggressive Behavior with Organic Causes

• Hormonal, metabolicMetabolic refers to metabolism, i.e. the entirety of chemical processes that take place in a living organism to enable life processes. Metabolic disorders can cause a variety of Diseases in Dogs and cats., and biochemical changes:
  Administration of medications and hormones (testosterone, cortisolCortisol is a steroid hormone produced in the adrenal cortex. It plays an important role in the body’s stress response, as well as in the metabolism of proteins, lipids, and carbohydrates. Cortisol also helps regulate blood sugar levels and suppress the immune system., thyroid hormoneHormones are chemical messengers produced by endocrine glands and released into the bloodstream to affect specific cells or organs in the body. They regulate numerous bodily functions, including growth, metabolism, and reproduction.)
  Altered hormoneHormones are chemical messengers produced by endocrine glands and released into the bloodstream to affect specific cells or organs in the body. They regulate numerous bodily functions, including growth, metabolism, and reproduction. ratios (neutering of the female dog, hypothyroidism)
  Disturbed ratios of neural messengers in the brain (serotonin/dopamine metabolism)
• InfectiousInfectious describes the ability of a pathogen to be transmitted from one individual to another and trigger an infection. It also refers to diseases caused by such pathogens. diseases, organ diseases
  Rabies
  Distemper
  Toxoplasmosis
  Lyme disease
• Organ diseases
  Hydrocephalus
  Epilepsy
  Portosystemic shuntA shunt is an abnormal connection between blood vessels or heart chambers that causes blood to bypass the normal circulatory system pathway. Shunts can be congenital (present at birth) or acquired.
  Circulatory disorders in the brain
  Tumors in the brain
• Brain injuries
• Poisoning (lead, organophosphates)

Treatment

Unwanted behavior and/or learned behavior can be well influenced by appropriate training and only rarely requires the support of a veterinarian. In case of serious problems, the help of a competent animal trainer is useful.

If the Aggressiveness is due to Pain, it is of course urgently necessary to determine the cause of the Pain and treat it accordingly with veterinary medicine.
In cats, a lot of patience and species-appropriate handling are necessary to enable a relaxed interaction with them.

If, on the other hand, aggressive behavior can be attributed to hormonal, metabolicMetabolic refers to metabolism, i.e. the entirety of chemical processes that take place in a living organism to enable life processes. Metabolic disorders can cause a variety of Diseases in Dogs and cats., and biochemical changes, as well as various infectiousInfectious describes the ability of a pathogen to be transmitted from one individual to another and trigger an infection. It also refers to diseases caused by such pathogens. and organ diseases, successful treatment of these will also lead to the disappearance of the aggressive behavior.