Definition
- Aggression is a behavioral strategy used to manage aversive situations.
- May be normal and appropriate in certain contexts.
- May be abnormal with serious deleterious effects on the cat's physical and emotional well-being.
- Aggressivity: describes both mood and temperament traits relating to the propensity to show aggression when environmental circumstances dictate it might be used.
Overview Of Types
Play Aggression (Toward People)
- Typically refers to a cat who scratches and bites the owners during play.
- Not true aggression but overzealous play without proper impulse control due to lack of training or proper intraspecific social feedback.
- The cat's intent is not to harm the person.
- Behavior encouraged and rewarded by owners through rough play with a kitten; when larger and stronger, becomes perceived as aggression rather than overzealous play.
Predatory Aggression (Toward People or Other Animals)
- Cats have an innate drive to “hunt” or show predation behavior, which includes stalk, hide, and pounce.
- Predation is not a direct function of hunger.
- Typically stimulated by fast movements and can progress to the cat hiding and waiting for an animal or person to walk by.
- Play is a common way for young cats to perfect predation skills; play aggression and predatory aggression may overlap.
Redirected Aggression (Toward People or Other Animals)
- Cats who see, hear, or smell a trigger and direct aggressive behavior toward the closest bystander.
- In some cases, one person or animal in the home becomes the designated victim, and the cat may bypass a nearby individual and look for the preferred victim.
- Some cats may stay aroused for 24–72 hours after a triggered event.
- Common triggers inciting redirected aggression are seeing another cat or wildlife outside or loud noises.
Fear/Defensive Aggression (Toward People or Other Animals)
- The cat will show body postures indicative of fear/anxiety and may use aggression as a strategy to manage that aversive situation.
- Typical behaviors shown include a combination of any of the following: hissing, spitting, piloerection, arched back, turning away, running away, cowering, rolling on its back and pawing (defensive position, not submissive position) if cornered.
Territorial Aggression (Toward People or Other Animals)
- Some cats, particularly male cats, show territorial behaviors in domestic home settings due to size and the presence of more resources (e.g., people, food, resting areas, feeding areas, elimination sites, etc.) to defend in a smaller area.
- Territorial behaviors include marking with urine, feces, or bunting (the rubbing of the cheeks on surfaces to deposit pheromones) and scratching (also deposits pheromones and leaves visual marker) and may be associated with aggression.
- In severe cases, the aggressor may seek out the other individuals and attack.
- Body posture with territorial aggression is assertive and confident.
Pain Aggression (Toward People and Animals)
Cats who are in pain may show aggression (hiss, growl, scratch, bite) when they are physically handled or prior to or after movements such as jumping onto or off a piece of furniture.
Maternal Aggression
A female cat may show aggressive behaviors toward individuals approaching her kittens.
Impulse Control Aggression
Cats who show intense aggressive responses to mild stimuli without much or any warning may have an impulse control disorder arising from dysfunctional serotonin neural circuits.
Frustration-Induced Aggression (To People and Other Animals)
Some cats have very outgoing, social personalities and exhibit aggression if the captive life indoors does not meet their behavioral needs.
Contact-Induced/Petting Aggression (Toward People)
- Cats will show early signs of aversion when people stroke their cats, with their ears going back and tail swishing.
- If physical contact continues, they typically bite.
- Owners often miss the early warning signs.
- When cats groom one another, they typically limit the grooming to the head region.
- Some cats appear to be particularly sensitive to being stroked along the dorsum, the common method used by owners.
Intercat Aggression within a Home
- Fifty percent of cat owners report fighting (scratching and biting) after introducing a new cat to the home.
- The number of cats, gender, and age are not significant factors in predicting which cats will show aggression.
- Any of the above categories of aggression are all possibilities for fights between or among cats.
- Fear/anxiety is the most common cause of intraspecific aggression.
Contributing Factors To The Pathophysiology
Behavior problems are typically multifactorial in cause, and Figure 1 is a diagram illustrating some of the more common components that need to be evaluated to accurately diagnose and treat aggression cases.
Systems Affected
- Behavioral-vary with type of aggression, occur alone or in combination: tail swishing/twitching, ears turned sideways or flattened, stiffening of shoulders/legs, crouching, dilation of pupils, hissing, spitting, growling, piloerection, staring, chasing, stalking, pawing, lunging.
- Cardiovascular-signs associated with sympathetic activation and HPA activation.
- Endocrine and Metabolic-long-term aggression associated with fear/stress/anxiety, symptoms associated with long-term activation of the HPA system.
- Gastrointestinal-with chronic HPA stimulation may see a cat more prone to anorexia and GI ulcers. With acute fear aggression: evacuation of the bowel and possible diarrhea. IBD possible in chronic stress.
- Hemic/Lymphatic/Immune-decreased immune response with chronic HPA stimulation; stress leukogram.
- Musculoskeletal-an outcome of the aggression may result in damage to the muscles from damage by the nails and teeth.
- Both the victim and the aggressor may suffer injuries. With chronic activation of the HPA, may see muscle wasting.
- Nervous-increased reactivity for up to 72 hours following an aggressive outburst. May see an increase in aggression with decreased provocation as the synapses in the amygdala become sensitized. Some animals may have decreased serotonin, causing aggressive outbursts. Depending on the type of aggression, may see ritualized motor patterns, shaking, or trembling.
- Ophthalmic-dilated pupils with sympathetic stimulation.
- Renal/Urologic-may see associated spraying or small amounts of urine on horizontal surfaces. May exhibit signs consistent with FLUTD with aggression that is due to stress/anxiety/fear.
- Respiratory-tachypnea in acute cases or when stressed.
- Skin/Exocrine-damage due to fights. Damage due to excessive grooming associated with fear-based aggression/anxiety/distress.
Signalment
- There is preliminary evidence that behavioral traits in cats vary by breed and gender.
- Males were more likely to show aggression to cats than females.
- Abyssinian, Russian blue, Somali, Siamese, and chinchilla breeds showed more aggression.
- Maine Coon, ragdoll, and Scottish folds showed the least aggressiveness.
Signs
- May appear at social maturity (2–4 years of age) except for play-related and should occur in specific social contexts/interactions. If onset occurs in an older cat, medical causes should be ruled out first.
- General comments: most owners are able to detect overt signs of aggression (biting, hissing, growling) but may miss more subtle signs of aggression that typically occur between cats (staring) and the resulting anxious behaviors that can result in aggression (meatloaf position, averting gaze, etc.). Videotapes of intercat interactions allow the clinician to assess the behavior.
Causes
- Underlying medical issues can cause aggression.
- Temperament/behavior is influenced by genetics, rearing, socialization, environment in which the cat lives, and types of interactions the cat has with people.
