Chapter 8 Feline Eliminative Behavior
The neonate cannot voluntarily urinate and defecate. Instead, eliminative behaviors are controlled for several weeks by the urogenital reflex. Stroking of the kitten’s perineal region or caudal abdomen, as a queen would do while cleaning her young, results in urination and defecation. When the young are not mobile enough to leave the nest, it is critical to their survival in the wild that the nest be reasonably undetectable, which requires that it have relatively little odor. Because the kittens can eliminate only when the queen is present to tactually stimulate them, the urogenital reflex ensures that she can consume their wastes and prevent their soiling the nest. Even after this period of relative kitten immobility, the queen continues to stimulate this reflex because the home nest remains the center of activity until the kittens are about 6 weeks of age, when it begins to share significance with other sites specific for feeding, playing, and eliminating.113 The anogenital reflex disappears between 23 and 39 days of age; however, kittens can voluntarily eliminate by 3 weeks of age.
Initially most of the queen’s grooming and ingestion of waste occur during nursing or shortly thereafter; however, as the kittens get older the queen may directly approach certain individuals. Commonly the kitten assumes dorsal recumbency with the limbs abducted. Younger kittens are passive until the grooming-toilet session is completed, and older ones tend to squirm.
Kittens have a natural tendency to “earth-rake” loose sand and dirt as a prelude to the use of this behavior in elimination. Around 30 days of age, a kitten begins to spend time in a litterbox or in soft dirt, moving the particles one way and then another. Ingestion of litter or dirt as a form of oral exploration is also common at this time. Because this can be expected, clumping litters are not appropriate for young kittens.88,89 Absorbent plastic pellets should not be used either. This oral behavior is usually followed within a few days by the species’ behaviors of eliminating in a certain area and covering the elimination.
The neural mechanism for eliminative behavior can be demonstrated to be functional by electrical stimulation of the hypothalamus at 2 weeks of age. Thus neurologic maturation of these pathways has occurred as long as 2 weeks before the actual onset of the behavior.34,76 The kittens learn the specific toilet area by observing the queen and by olfactory cues.
Because kittens naturally complement innate behaviors, such as burying wastes, with learned patterns, such as where to eliminate, a newly acquired kitten generally does not have to be “litter trained.” However, occasionally individuals such as orphans or outdoor cats do not have the opportunity to learn, and the owner must educate them. Young cats also learn surface and location preferences12 and should not be considered “trained” until at least 6 months of age.
It is initially important that any cat be confined to a small area to take advantage of the fastidious feline nature. This makes the litter readily accessible. It is not realistic to expect a kitten that spends most of its time in the living room to reliably use a litterbox kept in a back bedroom on the second floor.2 The owner should place the untrained kitten in the litter pan shortly after each meal and manipulate its forepaws to make digging motions. The kitten is allowed to jump out, so this process can be repeated one or two times.73 For the older outdoor cat that is becoming an indoor pet, the same procedures can be used, but it is often desirable to use dirt or sand initially and gradually change to litter. With these older individuals, particular care must be taken to keep potted plants out of the area so that the cat does not use the dirt in the pot for its toilet area. The plant could instead be protected by various forms of remote punishment or by putting decorative stones, pine bark chips, moth balls, or aluminum foil on the surface.2,80
Litter training may at first require leaving small traces of excretions in the box so that the smell can be used as a cue. If the kitten uses the area of the litterbox but not the box specifically, the owner can place the droppings in the tray to give it the appropriate odor and show the cat where the preferred area is. The litterbox location should be easily accessible yet afford some privacy and be relatively nearby. Cats prefer open large areas over the small covered box. Litter should not be scented and preferred types are fine grained. Although the cat instinctively eliminates in soft loose dirt, it can learn to use other locations either by itself or by special learning techniques. Litterbox substance is relatively easily changed from dirt or clay, typical of outdoor substances, to other loose material such as sand, commercial litter, wood shavings, or shredded newspaper. Most litters are 6 mm or less in particle diameter and all particles should feel similar in size to the cat.10 Preferences seem to go to clumping products and Ever Clean, the recycled paper product,10 over sand, which is more preferred than clay litter.48,49 Unshredded newspapers may even be acceptable to the cat. In fact, cats often choose to use whole newspaper lying around the home instead of a litterbox. It is also important to have a size appropriate for the size of the cats and at least one litterbox per cat.22,58,80,89,98 These should be available in multiple locations and various styles and sizes.102 Litterboxes should have urine and feces removed at least daily with some fresh litter added to keep litter depth at 2 to 3 inches. The box needs to be completely dumped every 2 to 7 days or whenever the odor gets strong to the cat. Clumping litter can be changed less often, unless there is a rapid accumulation of small pieces of feces, as happens with soft feces. It is important to remember that odor at 6 inches from the litter is stronger than that at 3 feet. Boxes should be washed each week with a mild detergent and discarded when they are old.
Certain individuals, particularly of popular breeds such as the Persian, may be exceptionally difficult for either the queen or the owner to litter train.13 It may indicate a genetic problem resulting from the popularity of the breed and consequent indiscriminate breeding. Perhaps “house trainability” was not considered in genetic selection, neurologic or learning deficiencies have been bred into the population, or cat domestication in general has created the difficulty.
Urinary postures and associated behaviors are ordinarily quite similar between the sexes. The cat usually digs a small hole in soft dirt or litter with its forepaws and then positions itself so that the urine is expressed into this area. The cat assumes a posture almost like that of sitting, except that the pelvic limbs are slightly abducted and the tail is held more rigidly, usually pointed caudally (Figure 8-1). Urine is forcefully ejected in a stream, probably because of abdominal pressure and urinary bladder contraction. When finished, the cat stands and moves dirt or litter over the urine with its forepaws (Figure 8-2). This happens 2.3±2.1 times a day,107 usually as short litterbox visits. Of these trips, 73% occur in the morning.60
Cats often learn on their own to urinate in a sink, bathtub, or toilet. Because some of the larger felids eliminate over streams, the domestic cat may adopt a more urban version to remove waste products. If this practice is undesirable, the owner can fill the tub with a few inches of water for several days and place a litterbox next to the tub. The water technique will not work if the cat straddles the sink when it urinates. In this case, an object like a cactus can be placed in the sink, with the litterbox nearby. For the cat that continues this behavior or that urinates in the toilet, the sink or toilet seat is lined with aluminum foil or plastic wrap and then filled with litter. Once the cat learns to use the litter, the owner moves the litter to a box beside the sink or toilet.11,54 The owner can gradually, as it is used, move the box short distances at a time until it is located in the preferred spot. The reverse technique can be used to train a cat to urinate in the toilet (Figure 8-3). The owner gradually brings the litterbox next to the toilet and then fastens plastic wrap to the toilet seat securely enough to hold quite a bit of litter, thus creating a litterbox. After a few days, the cat will accept a decrease in the amount of litter. As the plastic becomes visible, the owner puts some holes in it to drain the urine. The last stage is the removal of the plastic and litter. Because this posture is somewhat awkward for the cat, the animal may occasionally slip off the toilet seat, and repetition of some of the procedures may be necessary to retrain it.42,54
Because of the incidence of urethral obstruction and feline lower urinary tract disease, the relationship between eating and urination has been investigated. The frequency of urination was not different between cats fed by free choice and those fed twice daily.33 Those fed periodically did produce less urine and their urine pH level was lower in the morning and higher in the afternoon compared with cats fed ad libitum.33
Spraying urination is used by cats, particularly intact males, to mark the edges of its territory, mark an activating landmark, communicate familiarity for reassurance, and signal its presence, thus minimizing the frequency and severity of encounters with intruders.29,38 The odors of sprayed urine do not frighten other cats away,39,75,107 indicating they are more for informational purposes. Both sexes can distinguish urine from strange versus familiar males, with males tending to investigate urine odors longer.75 Because several cats may share a hunting area at different times, scents may be useful for avoidance.75 To spray urine, the cat stands with its tail erect and quivering, although a few flex their elbows to lower the forequarters132 (see Figure 3-17). Urine is ejected onto a vertical object in spurts that cover a relatively larger surface than normal urination, at a level 1 to 2 feet high. Earth raking afterward is rare.119
Because this marking behavior is sexually dimorphic, it is used primarily by intact tomcats and occasionally by females and castrated males when environmental situations become excessively stressful. Breeding males will spray two to four times more often than females or other males.75,82 This averages 22.0 times per hour for breeding males, 12.9 times per hour for nonbreeding males, and 3.6 times per hour for females.75 More spraying occurs near favorite hunting locations, by cats with larger home ranges, and when traveling.75 Only 14.8% of the episodes follow agonistic encounters.75 Male spraying peaks in the spring and then gradually decreases until late fall.82 No seasonal variation is reported for females.82 There is a genetic component to urine marking, making it more likely to occur in certain lines of cats.39
Emotional states affect renal circulation and thus urine formation. Excitatory states result in vasoconstriction, as in the intestinal vessels, because of neurogenic factors and a humoral component. During natural sleep there is renal vasodilation, probably resulting from vascular autoregulation.84 These physiologic factors result in decreased urine output during excitement and increased output during sleep.
Outdoor cats defecate 3.2±1.5 times in a 24-hour period,72,107 although there is quite a bit of variation depending on the diet. Newer concentrated foods can reduce the number of defecations to fewer than 1 a day. Behaviors associated with defecation resemble those used for normal urination. Posturing is similar, but the back is slightly more rounded and the perineum slightly higher off the ground (Figure 8-4). Cats may not dig as much before defecating as they do before urinating.107 Burying feces is uncommon outside the cat’s core area. Away from a home location, cats will bury feces only 45% of the time.82 This could apply to indoor cats living in a large home. When feces is not covered, it tends to be along hunting paths or on elevated sites, with two or three scats accumulating per site.75 Territorial males are more likely to use these prominent sites,22 but the consensus is that cats do not mark with feces.7,34,37,40
The earth raking associated with burying feces is initiated by the odor of fecal matter, so most cats will sniff the feces before covering.107 Feces that is not sniffed is seldom covered and not all feces that is sniffed is covered. Cats that miss the litterbox may perform earth raking on the floor, even though they move only air.74 Odors from other sources, including some foods, can also stimulate this behavior. The artificial selections of domestication have changed some of the genetic factors of this behavior, and consequently some cats do not bury their feces even in their core area. Conversely, some cats are so fastidious that they cover not only their feces, but any other cat’s exposed feces.
There is no one toilet area for the free-roaming cat, so feces are widely spread. This dispersal, along with the covering behavior, serves as a form of parasite control. Because the concentrated odor of fecal matter may actually inhibit the use of a certain area, litterboxes must be frequently cleaned.
Housesoiling is the most common problem in cats.3,98 In cat owner surveys, researchers found that 47% to 55% of owners have a behavior problem with their cat, and 10% to 24% of pet cats will show an elimination problem at some time in their life.10,12,31,57,98 Specialists dealing with behavior problems may have 45% to 65% of their cat cases related to eliminative problems.83,98 Cats that have at least weekly elimination problems are at the highest risk to be surrendered to an animal shelter.108 To work effectively with these cats, history taking is the most important part of the workup, because the most common reason for failures to use a litterbox are directly related to the litterbox, its contents, or its location.65 A number of methods can be used, including a taxonomy.3 Regardless of the specific approach, one must determine which cat is soiling, what specific type of elimination is occurring, where the cat is eliminating, and how long the behavior has been occurring. The history of litterbox use by the cat and box maintenance by the owner is also necessary. In multicat households, an owner may assume a particular cat has been housesoiling because it “looks guilty” or they do not particularly like the animal. Because treatment of the wrong cat is not successful, the true problem animal must be found. Isolation of individuals may indicate which cat is soiling. Other options are to give salicylates and test for their presence in serum or urine with ferric chloride.114 Fluorescein can be given orally or subcutaneously to a single cat and fresh urine spots checked with an ultraviolet light47,54,55,119; however, owners should be cautioned that carpet or clothing can be stained by the fluorescein. The injection is 0.3 ml of a 10% solution, and the oral preparation is 0.5 ml of the 10% solution or six large animal ophthalmic strips (9 mg of fluorescein per strip) in two no. 4 gelatin capsules.22,97,121 Check the urine in 1 or 2 days. A washout period of 24 to 48 hours is recommended between cats.119
The specific type of eliminative problem must be determined. Differentiate feces from urine and spraying from urination. If the owner has not seen the cat eliminate outside the litterbox, determine whether the wet spots are on vertical surfaces such as a wall or drape or whether a specific item or person is targeted such as the owner’s pillow, dirty clothes, or favorite chair. A positive answer to questions regarding any of these indicate spraying (or urine marking) is the problem.
Where the housesoiling occurs may also indicate why or suggest an appropriate course of action. Owners may indicate the cat is soiling all over the house when the actual problem may be confined to one or two rooms or even spots. Areas near windows and doors or where cats can see outside are favorite targets for spraying when strange cats roam, especially during the mating season. When items belonging to a certain person are urinated on, there is a disturbance with that individual that bothers the cat. If the problem is confined to a single room, it can be closed off and the problem easily stopped.
Litterbox maintenance requires several questions.99 The number, size, and location of the boxes should be determined. Also, information about the type of litter used; recent changes; and the frequency of removing feces, removing urine, and complete litter changes are needed. When and how is the box cleaned and how often is the box replaced?
Another important piece of information needed is how long the housesoiling behavior has been occurring. A single episode of missing the litterbox rarely requires intervention, but a 5-year history of not using the box at all is very difficult to change. If the cat never learned to use a litterbox, it is not reasonable to expect that it will begin just because it moves to a new home or the owners get new carpet. Factors that contributed to the onset of housesoiling can be different from those maintaining it,66 so early and current factors may need to be considered.
A thorough physical examination should be part of the evaluation of housesoiling cats. Palpable abnormalities such as urinary calculi, abnormal kidney size, joint crepitus, or visible evidence of poor body or hair coat condition can point to medical causes of behavior problems.
Laboratory evaluation of most of these cats is also indicated. This is particularly true for geriatric animals because of the increased likelihood of several conditions.64,97 Anatomic abnormalities, calculi, constipation, crystalluria, cystitis, diabetes mellitus, diarrhea, feline immunodeficiency virus (FIV), feline infectious peritonitis (FIP), feline leukemia (FeLV), feline lower urinary tract disease (FLUTD), food allergies, hyperthyroidism, incontinence, inflammatory bowel disease, internal parasites, interstitial cystitis, maldigestion/malabsorption, metabolic encephalopathies, pain, and pyelonephritis can cause housesoiling problems that require medical intervention. One study of spraying cats found 38% had abnormalities of the urogenital tract.35,36 Because FLUTDs are a very common cause of inappropriate urination, it is important to learn where the cat is soiling; bathtub, sink, bath mat, and laundry are often used with this problem.115,121 Dietary information should also be obtained because of the link between diet and FLUTDs.15 Diet information is also important for constipation-related inappropriate defecation, particularly where the history may suggest occasional running in pain.115 FeLV- and FIV-positive cats can show behavior changes such as the loss of housetraining, so testing for these diseases is appropriate.32 In addition, if drug therapy is going to be used, a minimum database of a complete blood cell count, blood chemistry, urinalysis, and thyroid screen should be done.
The failure to use a litterbox can be classified in several ways. The method used here is to determine the type of housesoiling. It divides inappropriate elimination into defecation and urination. Marking can be urine marking, including spraying, or feces marking, which is extremely rare in cats. Another classification technique is to look at etiology such as litter aversion, surface preference, location preference, or location aversions.*
The prognosis for any of these problems depends on many factors, not all of which apply to any given situation. Included are (1) duration of the problem—the longer the problem, the more difficult it is to stop; (2) sex of the cat—males have an increased tendency to spray; (3) neutered status—intact cats are more likely to spray; (4) number of other cats in the home—multicat households have more problems; (5) number of areas soiled—more locations are more complicated; (6) ability to control stimuli—keeping the cat indoors or cleaning a box daily instead of weekly are relatively easy for most owners, whereas minimizing cats roaming nearby probably is not; (7) previous history of litterbox use—cats who have used a litterbox are significantly more likely to use the box again compared with a cat that never used one; (8) temperament of the cat—innately nervous individuals are more difficult; (9) ability to use drug therapy—drug therapy can be helpful in certain cases if owners can/will use medication; (10) coexisting medical problems, which can exacerbate problems or complicate treatment; and (11) owner commitment—magic cures are rare. Owner expectations, information about what has already been tried, and willingness to try different things are important pieces of information.6 It is constantly amazing how many owners have lived with a housesoiling cat for several years and want the problem instantly stopped because their new carpet has arrived. Others get a cat from the shelter with a history of three previous owners having surrendered it for housesoiling but who cannot believe the cat would soil in their home too. Many owners will have partial success with their own therapies, but more than 80% need professional interventions.57 First, owners must not punish a cat for housesoiling. Doing so only increases the level of the cat’s stress, which may aggravate things further, and it does not change the original motivation.61
Urine marking is a common behavior problem, constituting up to 44% of the housesoiling complaints.* This number is probably low as well, because urine marking on horizontal surfaces is commonly diagnosed as inappropriate elimination unless specific horizontal targets can be identified. Urine spraying is generally related to sexual behavior and is commonly described as a problem of tomcats during the mating season. Male-female differences in response to lesions in the medial preoptic-anterior hypothalamic region support the concept of spraying as a sexually dimorphic behavior. Lesions usually stop spraying by males but have no effect in females.56 Urine spraying is a behavior that is mainly territorial or anxiety based. The resident cat may spray to scent mark whenever it becomes uncomfortable with its surroundings, such as when there is decreased attention, punishment, owner absences, changes in routine, changes in surroundings, overcrowding, cat aggression, competition, introduction of a new cat, smell of another cat, or other stressors. The incidence of spraying is directly proportional to the number of cats in the household, increasing from 25% in single-cat households to 100% in households with more than 10 cats.11,66,71,101 However, when spraying does occur, the severity of the problem is generally worse in single-cat homes. One study showed the incidence of spraying to be 16.1 marks per week compared with 7.4 marks per week in multicat homes.68 About 5% of females and 10% of neutered males may also mark, but the behavior for them usually requires a higher threshold than for tomcats. Estrous females will spontaneously mark too. Some cats seem to be more easily upset by changes, so it is likely that individual temperaments also influence the tendency to urine mark.
Because male cats (77%) and cats from multicat households (89%) are the most likely to have urine-marking problems,110 one must understand and address the social causes of urine marking.102,103 Causes likely to result in urine marking include agonistic interactions with outside cats (49%), aggressive interactions with other cats in the home (28%), limiting outdoor access (26%), moving into a new home (9%), new inanimate objects in the home (6%), and interactions with the owner (6%).110 Items most commonly targeted include (1) furniture, (2) walls or windows where the cat sees outside cats, (3) other walls, (4) appliances, and (5) novel items.110 The remedy basically consists of altering either the cat’s normal response or the stimulus. These may be accomplished by eliminating the environmental source of the problem, isolating the resident cat from the offending environment, altering the perception of stress, or minimizing the hormonal influence of the situation. The owner needs to have multiple feeding areas, multiple litterboxes, and several single-cat perches of different heights scattered throughout the house.97
Certain episodes of urine marking seem to involve vindictiveness on the cat’s part, almost as though the cat were punishing its owner for some slight. “Spiteful” eliminations probably do occur, such as when the cat urinates on the owner’s bed or clothes immediately after a scolding, a trip out of town, or the introduction of a new cat, but definite proof of spitefulness is extremely difficult. When the resident cat deposits urine on objects belonging to a specific person, it may indicate the cat has singled out that relationship as less than desirable. When the objects targeted are more horizontal than vertical, the owner will describe a squatting posture. This makes it difficult to determine whether the cat is marking the object or housesoiling on an absorbable surface. Historical information about location and timing of the event relative to potential stressors is particularly important. When several objects are urinated on and they all belong to a particular individual with multiple people around, there is a good probability the cat is urine marking. Additional history may show the person is not fond of cats, and of course, the cat’s behavior does not help. The simplest solution usually involves having the targeted person feed the cat. It is best if the cat can be given one or two small meals of canned food so that it has a strong desire to approach. Other people in the household should minimize their interaction with the cat during this time.
The treatment protocols for marking behavior usually involve several approaches at the same time. The first is the most obvious, because castration eliminates spraying behavior in 87% of tomcats. Testosterone will reach levels typical for a castrate (less than 50 ng/dl) within 8 to 16 hours after surgery,49 so a fairly rapid change in behavior should be expected. Of those that respond, 78% exhibit a rapid postsurgical change, and the remaining 9% change gradually over a few months.50 Approximately 10% of prepubertally gonadectomized cats will start spraying later in life, indicating learning and testosterone are not always factors.51,54,116 Males are also more apt to spray if there are female cats in the household51,54 or if they detect an estrous female in the presence of urine odors of other males.106 About 5% of spayed females spray.52,53,91
Drug therapy is helpful and often necessary to get urine marking under control (Figure 8-5). A number of different drugs can be used, although success is somewhat mixed. Good comparative studies have yet to be done. The progestins used to be the drugs of choice, particularly medroxyprogesterone acetate and megestrol acetate. These products are effective in approximately one third of the cases, working better in male, single-cat households.23,44,47 Males responded positively 50.0% of the time in multicat homes and 85.7% of the time if they were the only cat.23 This compares with a success rate for females of 16.7% in multicat environments and 37.5% in single-cat households.23 The progestins will also depress spermatogenesis and stimulate the appetite, in addition to having some serious side effects if used long term.77,109,112 Other hormones, such as repository stilbestrol, ethylestrenol, and progesterone, have been used occasionally to control spraying, but their side effects can also be serious.7,96,122 Currently anxiolytics are the most helpful. The benzodiazepine tranquilizers, particularly diazepam, are useful if stress is the precipitating factor in housesoiling.2,61 They help in social facilitation and make cats less reactive to stimuli and surroundings.103 These drugs are more helpful than hormone therapy when the problem involves females and/or multicat households.85,87 In studies, diazepam eliminated or reduced spraying 55% to 74% of the time.23,92,119 Male cats in multicat homes were positively affected 63.6% of the time, and those in single-cat homes were positively affected 33.3% of the time.23 Females in multicat environments were positively affected 60.0%.23 There is a high probability of reoccurrence when medication is stopped, perhaps because of dependancy to the drug.23,92 For this reason, gradual reduction of the dose by 10% to 25% per week is recommended.119