By Theresa L. DePorter, DVM, MRCVS, DECAWBM, DACVB
Social tension between housemate cats may manifest as overt aggressive encounters or passive avoidance of cats that live in the same home. The conflict may be obvious if cats are screaming or subtle if cats are simply avoiding interactions. While many cats form strong affiliative bonds with housemate cats, characterized by co-sleeping, nose-touching, and allogrooming, other cats forced to live together unwillingly may display a wide range of overt or passive aggression.
Social conflict may begin when the cats are first introduced; or it may develop among cats that formerly had good affiliative bonds, either following a specific incident or due to gradual changes in the relationship. Overt displays of aggression include growling, hissing, screaming, spitting, attacking, chasing, and biting. Passive displays include staring, blocking, and hiding. Some cats choose to run away or spend more time outside in order to avoid conflict.
Conflict between housemate cats may have elements of fear, anxiety, self-defense, or territorial defense. Regardless of the underlying motivation and etiological cause, people don’t like seeing their cats in distress, so conflict between housemate cats is a common cause of relinquishment. Other behavior consequences of social conflict may include urine retention, undesired elimination outside the litter box, or urine marking.
According to the AVMA, there are 81.7 million owned cats in the U.S., versus 72 million owned dogs; and 35.4 million households own at least one cat. Cat-owning households have a mean of 2.1 cats, while dog-owning households have a mean of 1.6 dogs (American Pet Product Manufacturers Association, APPMA). Cat owners in the South keep more cats per household (3.2 cats) than any other region; compare New England (1.9 cats) and the Midwest (2.4 cats) (U.S. Pet Ownership and Demographic Sourcebook, AVMA). Multiple cat households are common and keeping the peace is important for the emotional well-being of all cats in the home.
Cats may display conflict the first time they meet each other, or they may get along for years and then begin fighting. A single "tragic event" can start a series of aggressive encounters that may persist long term or become more passive. Cats can become upset about a stray cat outside their home, or they can be startled by a sudden noise or distressed following a troubling car ride. If, at that exact moment, one cat locks eyes with another, an aggressive posture or fight may ensue. From that moment, the cats may not get along.
Cats are poor at reconciliation. That is, cats lack the inherent skill to resolve a conflict, except by fighting or fleeing. An example of severe cat-to-cat interaction may be seen in this video. These cats are locked in a stand-off, and neither cat has the skills to resolve the problem nor just walk away.
Cats don’t reconcile well because cats don’t generally offer appeasement gestures to resolve a social dilemma. If they are distressed or worried about an outcome, cats either flee or freeze. Other very social species, such as dogs, horses, and people, have the social skill set to “appease,” that is, a social skill package utilized to resolve differences. People may forgive and rebuild relationships following a disappointment or argument.
Consider the post "Forgiveness vs. Reconciliation: Forgiveness Fact and Fiction" by Ryan Howes Ph.D., ABPP. Even for people, forgiveness and reconciliation are not the same. “Reconciliation is an interpersonal process where you dialogue with the offender … begin to reestablish trust.” People need people. Cats are solitary and independent: Tight social bonds with other cats in their social group are not essential. Cats are indeed social and may form close social bonds with some feline friends, but they are not dependent on those social relationships to survive.
Cats have complex interactions and relationships, but they may not have a good reason to mend a soured relationship. Cats communicate by body language, so we may observe flattened ears, a crouched body with the head low, or a swishing tail. A defensive cat will hiss or scream. An aggressive cat may growl. Cats may display aloof disregard and avoid cats they dislike. Cats that are most comfortable together will sleep so close that they are intertwined and groom each other around the head.
Steps for peaceful resolution of feline social tension:
- Space. Provide enough real estate for each cat to enjoy his/her preferred resting, playing, and eating activities while still avoiding stressful encounters with housemate cats.
- Distribute important resources. Each cat should have easy access to food, resting areas, scratching posts, toys, and litter boxes without encountering an unfriendly cat.
- Don’t force cats to interact. Each time the cats experience an aggressive encounter, they are learning to fight next time. Patience is essential.
- Never punish or startle cats that are displaying aggression or fear. No yelling, squirting or scaring. Cats may stop fighting and flee, but the overall tension will not be reduced.
- Guide cats to move away from an aggressive or tense encounter. Encourage either cat to move away by using a sweet, gentle tone of voice. You may coax your cat using food, treats, or toys. You may make noises that you know cause your cats to happily investigate (i.e., go to the kitchen and open a can of tuna).
- Pavlovian or classical conditioning. You can change the cat’s emotional association by pairing the presence of each cat with the occurrence of a desirable reward.
- Anxiolytic. It may be necessary to reduce anxiety and distress with medications, pheromones, or natural supplements. Discuss options with your veterinarian.
- Health. Be sure your cats are healthy and see their veterinarian regularly. Underlying pain or discomfort such as osteoarthritis or dental disease can contribute to irritability and social tension.
- Be realistic. Some cats are not going to get along. Some cats will become friends. Some cats will achieve “aloof disregard” for each other.
Cats communicate with each other by leaving and detecting messages in the form of pheromones in the environment. People use words to write a blog post, leaving a detailed message for the receiver to consider at another time. Similarly, cats leave pheromone messages in the environment for other cats to “read” at another time.
Pheromones are natural substances secreted from sebaceous mucous or sweat glands that induce an emotional, physiologic response in an individual within the same species. The chemical diversity of pheromones ranges from small volatile molecules to sulfated steroids to large families of proteins. These compounds are classified as pheromones based upon their binding to specific receptors and subsequent influence on behavior, rather than based on similarity of molecular structure.
Cats deposit pheromones by leaving scents in the environment by means of face rubbing, urine marking, or scratching on upright surfaces. Pheromones are received by the vomeronasal organ (VNO), a paired tubular structure located just above the hard palate near the internasal septum. Cats display a specific flehmen response called the “gape” to gather pheromones into the passageways. The gape expression follows olfactory investigation and is characterized by a tongue lick to the nose, followed by the cat’s gazing in a thoughtful, preoccupied fashion while the upper lips are raised slightly and fluffed with the mouth slightly open. Upon exposure to pheromones, these olfactory receptors in the vomeronasal organ stimulate structures within the limbic system that alter the emotional state or activate physiologic effects.
Some of these chemical messages left by one cat for another can allow a cat to avoid potentially aggressive while others modulate social interactions. Feliway® is a synthetic analogue of the F3 fraction of the feline facial pheromone, which is deposited by the cat when facial-marking and chin-rubbing on either objects or people. This creates a familiar, comforting scent of “self” in the environment. Appeasing pheromones, produced by the feline mother in the first few days after giving birth, are perceived by the kittens and play a role in their attraction and attachment to the mother. Appeasing pheromones, which are derived from the secretions of the mammary sulcus, may actually be useful to aid in reconciliation. Commercial pheromones encode a favorable message into the cat’s environment and thus influence the bias of the cat’s emotional response.
Recently, the effectiveness of a new commercial feline appeasing pheromone, Feliway MultiCat®, on inter-cat aggressive conflict has been established. Feliway MultiCat® by Ceva Santé Animale was evaluated for efficacy to reduce aggression between housemate cats by randomized double-blind placebo-controlled trial in 45 multi-cat households [Pheromone (n=20), placebo (n=25)] that reported aggression for at least two weeks (average=822 days). Each household included two to five cats.
Participants first attended a group meeting and the veterinary behaviorist described behaviors to be monitored for seven weeks using the Oakland Feline Social Interaction Scale (OFSIS), which assessed the frequency and intensity of 12 aggressive interactions (e.g. bite, swat, stare, block, hiss or scream). Participants were provided directions for safely handling aggressive events. Punishment techniques were discouraged. Plug-in diffusers with Feliway MultiCat® or placebo were utilized for 28 days. Participants completed a daily diary of aggressive events and weekly social interaction scoring. Baseline scores were similar.
The pheromone group showed a greater reduction in conflict score than the placebo at days 7, 14, 21, and 28, which continued post-treatment at days 35 and 42.3 Cat appeasing pheromones appear to be a promising new treatment to reduce social tension among cats with a history of aggressive or avoidant interactions. Using analogues of feline communication pheromones, we can speak in a language cats understand.
More research is being done regarding the complexities of feline social interactions in multiple cat homes and how to alleviate the social tension and the chronic distress of living in a strained feline relationship.
Theresa DePorter is a board-certified diplomate in the American College of Veterinary Behaviorists (ACVB) and the European College of Animal Welfare and Behavioural Medicine (ECAWBM). She received her Doctor of Veterinary Medicine degree from Purdue University and her Bachelor of Science in Biology in 1992. She has been seeing behavior consultations at Oakland Veterinary Referral Services in metropolitan Detroit, Michigan, since 2004.
1. Cozzi A., Monneret P., Lafont-Lecuelle C., Bougrat L., Gaultier E., and Pageat 2009. The maternal Cat Appeasing Pheromone: exploratory study for the effects on aggressive and affiliative interactions in cats. Proceedings of the 7th IVBM, Edinburgh, Scotland, 113-114.
2. DePorter T. Exploration of possible clinical applications for Cat Appeasing Pheromone: multiple case review. Proceedings of the 9th IVBM, Lisbon, Sept 2013, p173.
3. DePorter T, Lopez A, Ollivier E. Evaluation of the efficacy of a new pheromone product versus placebo in the management of feline aggression in multi-cat households. Proc. ACVB / AVSAB Veterinary Behavior Symposium, Denver, 2014.