Felipedia

Intercat aggression

Cats, like dogs, can be aggressive to other cats for a variety of reasons. This protocol focuses on cats that are aggressive to other cats because of concerns about status or rank. Some of these cats may have other problems; therefore it may be necessary to refer to the appropriate protocol for help with those problems.

Cat social systems have been less intensely investigated than have those of dogs. When given the choice and sufficient food resources, cats tend to live in family groups of related females. One or a few males usually control all the mating. Cats are seasonally polyestrus (meaning that they come into heat more than once a year, but there is a seasonal effect) and they are induced ovulators (meaning that mating causes them to ovulate and ends their heat cycle, usually with a pregnancy). The social system of cats means that not all males will have mates. This is the primary reason that intercat, in this case intermale, aggression is seen--males fight with each other over access to family groups and to females in heat. Most cats in urban areas in the United States are both indoor cats and neutered; thus intermale intercat aggression is not a common problem for most people with pet cats. It can still be a common problem for people who live in areas where there are feral or free ranging cats.

For the previously mentioned situation to occur, it is not sufficient that male cats are sexually mature--that happens at about 6 months of age. They must also be socially mature. Social maturity occurs in cats sometime between 2 and 4 to 5 years of age. There has not been much research in this area, but studies of free-ranging domestic cats indicate that cats in this age group start to take some control of the social groups and their activities. Social maturity is an event independent of sex or reproductive status (i.e., it also happens for neutered animals). When cats become socially mature, some of them fight over status within a household. These fights can be between males, between females, or between males and females. Fights may be less common between females than in the other pairings, because females live within family groups, but there are no data to indicate that this is so. Regardless, the cats will contest resources or access to resources. The resources may be food, water, perch sites, sunny windows, areas where the cats can survey the environment (French doors or picture windows), attention from people, and so on. There may be no true or actual threat to access to these resources. The change can be in one cat's perceptions of how much control it wants over the environment, over access in the environment, and over its housemates' behaviours.

Typically, intercat aggression occurs either between cats that have only recently been introduced or between those that have known each other since kittenhood. Regardless, it usually occurs when one of the cats becomes socially mature or when that cat perceives that another cat in the household is becoming socially mature. Clients often comment that the cats lived together perfectly well for the first 3 years of their lives and they find the new aggression particularly puzzling.

Cats can exhibit both active and passive aggression. Studies have shown that cats that are more familiar with each other or those that are less evenly matched often exhibit passive aggression. Cats that are less familiar with each other and those that are evenly matched often exhibit active aggression. Very confident cats are superb at exhibiting passive aggression. Unfortunately, clients often fail to recognize one cat's behaviours in this context as aggressive and may not realize that an aggressive situation is developing until the other cat either begins to hide, fight back, or hiss when it sees the aggressor.

Behaviours involved in active aggression include hissing, swatting, piloerection, stalking, wrestling, and biting. Passive aggression can be subtle but is usually unmistakable once clients know what signs to look for. Cats that are very confident do not back down from other cats; they may even set up the social situation so that the cat that they are challenging is denied access to an area, must avoid an area, or must take a tortuous path to get to something that it wants. Passive aggression involves stares and a lowering of the head and neck while elevating the rump and piloerecting the tail and tail base and may be accompanied by a low growl.

Cats that are controlling, confident, and successful at this usually only have to use passively aggressive strategies. These cats will stare at another cat and the second cat will leave the room. If the second cat re-enters the room and sees the aggressor, its presence alone may cause the second cat to flee. The victims of passive aggression are often found to spend increasingly large amounts of time away from the family, in areas of the house that others do not use (the basement), or spend time only with the clients when the aggressor is absent. This form of aggression can be very difficult to recognize because of its subtlety.

Clients often notice that the controlling, passively aggressive cat may also exhibit marking in the presence of the other cats or in their absence. The most common form of marking involves rubbing of the cheeks ("bunting"), head, chin, and tail on people, doorways, and furniture at cat height. Unfortunately, marking can also involve urine.

Urine marking generally acts as a flag for some form of aggression. Marking can involve squatting and urinating or defecating (nonspraying marking) or, the behaviour with which people are more familiar, spraying, in which the cat treads and kneads, raises its tail, and flicks the tip of it while spraying urine on a vertical surface. Spraying is a sexually dimorphic behaviour. This means that males more frequently exhibit it. Regardless, both males and females spray, and neutering animals of either sex reduces the frequency of marking but does not completely eliminate it. Spraying or nonspraying marking can be exhibited in either active or passive aggression by either the aggressor or the victim. It is not necessary for marking to be present for intercat aggression to occur.

Active aggression is far more physically risky than is passive aggression. In some but not all circumstances, if one cat is willing to defer to the other (let it eat first, let it have the best perch sites, groom it), the aggression will resolve. This is the theory behind tolerating some aggression when cats are initially introduced (see "Protocol for the Introduction of a New Pet to Other Household Pets"). However, if one cat refuses to tolerate the other or neither cat will acquiesce to being the lower-ranking cat, the aggression will intensify. Cat bites are very injurious because of the depth of the puncture. All cat bites-to people and cats-should be treated by competent medical help as soon as possible.

Treatment for intercat aggression focuses on establishing a social order that is tolerable for all cats involved and that minimizes danger. These cats may never be best friends, but perhaps they can live together nonstressfully. As is the case for interdog aggression, if one cat is acting deferentially to another and the cat to which it is acting deferentially is still aggressive, great pains must be taken to give status to the cat that is being victimized. Because the aggression between the cats often has been ongoing for a long time before the clients recognized it--particularly if it involved passive aggression-the treatment of intercat aggression may be difficult. In some cases the best solution may be to place or find a new home for one of the cats. Unfortunately, the cat that is most easily placed is the cat that is being victimized. Because this is a condition involving social status, the introduction of more cats into any household with aggressive cats may put the new cats at risk for entering into the aggressive cycle. The more cats in the household, the greater the potential for aggressive problems.

Checklist

1. Neuter all cats.

2. Trim all nails as short as possible.

3. Whenever the cats are not directly supervised, sep rate the cats involved in the aggression. This may mean that two of three cats in the household can stay together, but that the third one must be isolated. The cat that is the aggressor should be banished to the less valuable or less desirable area. Do not lock the aggressor in a dark closet, a dank basement, or a cold garage--this only teaches the cat to avoid you. Instead, if the aggression occurs in the bedroom or in front of the picture window, let the cat that is being victimized have the valued area and put the aggressor into a neutral area (a spare room). Remember to provide water and litter boxes for all cats.

4. Determine whether you can find a distance at which the cats can see each other but at which they do not react aggressively while they eat. If you can, you have a reasonable chance of being able to convince the cats to tolerate each other. Place a food dish for each cat at this distance. Make sure the food is something they crave. You may have to forgo ad libitum (free choice) feeding with aggressive cats. Give the cats small amounts of food and use frequent feeding opportunities. If you can find a distance where the cats eat happily and show no signs of aggression or fear, let them eat at that distance for a few days, then gradually start to move the dishes closer together 2 cm at a time. The goal is to have the cats eat side by side. If you can achieve this goal the cats usually will tolerate each other. If you reach a distance where the cats exhibit aggression, anxiety, or fear, move the dishes back to the last place where the cats seemed happy. Gradually try moving the dishes closer together again. If you cannot succeed in moving the dishes closer after repeated tries, let the cats eat at a distance at which they are happy. Remember, it is important to reduce anxiety, especially for the victim. Be vigilant for subtle signs of aggression such as staring. Monitor feeding time and intake. If you notice that the victimized cat is no longer finishing food that it likes or is eating quickly and leaving, threats are probably involved.

5. If marking is involved, refer to the "Protocol for Cats With Elimination Disorders."

6. When you are able to supervise the cats, they can mingle under the following conditions:

- When they each have a bell on their collars that allows you to distinguish between individuals

- If you hear the problem cats approach, you are willing to visually monitor the situation

- If you carry a water pistol, a compressed air canister, a whistle, or a foghorn with you at all times, and at the first sign of any aggression you interrupt the cat by directing the device toward the aggressor (use some common sense in your choice of a device to interrupt and correct the cats; if your cat loves to play in water, water pistols will not deter it unless they have a small amount of vinegar or lemon juice in them; if you have a fearful animal or a baby in the house, or if you live in an apartment, a foghorn may not be the best choice)

- If the threats escalate to frank aggression, do not reach between the fighting animals--instead make sure that a blanket is available that can be thrown over the animals or a broom or a piece of cardboard is available that can be shoved between the cats.

7. Use harnesses and leashes for all involved cats. If there are two or more people in your household, each should take turns monitoring each of the cats. If you are alone, attach the leash of the aggressive cat to a piece of furniture and hold the leash of the other cat. The cats should be restrained at a distance at which they cannot connect with each other even if they lunge. Find a food treat that the cats crave (small pieces of cooked shrimp, chicken livers, tinned sardines or anchovies, or tiny pieces of shredded chicken). Any time the cats ignore each other, tell them that they are terrific and give them a treat. If the aggressor voluntarily looks away from the other cat, reward that. If the victimized cat stares at the aggressive cat, reward that. Do not give a treat to any cat that shows any signs of aggression, fear, or anxiety. These signs include shaking and hiding.

8. Use a harness to correct the cat verbally or with a startle at the first sign of any aggression. If the aggression continues, banish the aggressive cat.

9. Use the harnesses to arrange the cats so that they cannot reach each other. Then alternate between the involved cats and groom and massage each cat. Start with the cat that is being victimized by the aggression. The goal is to get them to not react and to ignore each other. Any cat that reacts aggressively is banished. You can couple a favourable response to food treats. If the cats ignore each other, gradually begin to move them closer together. They should not become distressed or aggressive by the moves; if they do, separate them and try again at a greater distance.

10. If the cats are able to lie side by side without becoming distressed or aggressive and if they can eat together, you can leave them alone for gradually increasingly longer amounts of time. If you notice, at any time, that any cat is injured or is avoiding the other cat, repeat the previously mentioned steps. Some cats will never tolerate being close together but can live perfectly happy, separate lives in the same house.

11. Cats generally require and use more space than the average house or apartment affords them. The addition of three-dimensional space can help. Consider the addition of kitty condos, cardboard boxes, beds, and crates to all rooms once you have started to reintroduce your cats.

Some problematic cats benefit from antianxiety medication. This may be an option for your cat. The role of medication should be to augment behaviour modification, not replace it.