Cats, unlike dogs or people, are obligate carnivores. In other words, cats must eat animal tissue to maintain their long-term health. The cat's reliance on animal tissue comes from her evolution as a predator. Left to her own devices, away from the comfort of the cat owner's kitchen, the cat survives in the wild as her ancestors did, on whatever small prey is available in the habitat.
In the wild, cats may eat 10 (or more) small meals in a 24-hour period. In the average home, however, many of us feed our cats differently (for example, two relatively large meals every day). In some cases, this schedule may lead to feeding-related behavioral disturbances.
In the Wild
Cats are opportunist hunters. They shift their choice of prey to take advantage of the types of wildlife available in their geographical area, or to respond to seasonal changes in prey populations. Numerous studies show that small mammals, such as mice, rats and young rabbits, typically comprise 75 percent or more of a hunting cat's diet.
Feeding behavior in cats involves two stages: an appetitive phase and a consummatory phase. The appetitive phase includes: hunting, capturing and killing prey. The consummatory phase involves the devouring of prey. The concept of behavior being divided into appetitive and consummatory phases can also be applied to the feeding behaviors of domestic cats living indoors, even though they are not often presented with opportunities to chase and capture their food!
For most indoor cats, the appetitive phase has been reduced to begging for food ("razzing" the owner) or seeking out scraps of food and stealing them off tabletops and counters. The consummatory phase for cats with this lifestyle amounts to munching on dry food and/or gulping down the contents of a can.
The lack of opportunity to perform the full range of species-typical behaviors is a significant difference between indoor and free-ranging cats. With regard to feeding, the unfulfilled behavior includes chasing, attacking, killing and carrying prey to their home territory, ripping skin, chewing around bones, and caching the remains.
Plant eating is quite a common practice in household cats, and it is normal behavior. In the wild, cats sporadically feed on grass, perhaps to obtain cellulose fibers, which may aid in digestion. Indoor cats may try to quench this need by eating houseplants. This behavior problem may be resolved by providing the cat with a suitable alternative source on which to graze, such as edible grass (sold at pet stores). Poisonous plants should be hung out of the cat's reach or donated to non-cat households.
Weaning represents a period of major transition for young mammals, marking a change from complete dependence on parental care to partial or complete independence.
Under free-living conditions, mothers start to bring live prey to their kittens from 4 weeks after birth onwards, and kittens may start to kill mice as early as the 5th week. Four weeks is also the age at which kittens normally start to eat some solid food, heralding the beginning of the weaning period.
With regard to the human-animal bond between an owner and a cat, it is thought that the cat may perceive the owner as a parental figure, since it is the owner who takes over the maternal role of providing food. This misperception on the part of the cat is thought to underlie some behavioral problems related to nursing and maternal-care seeking behavior, such as inappropriately directed non-nutritional sucking, obsessive hair playing, and overattachment.
As weaning progresses, kittens become responsible for initiating bouts of nursing. Weaning is largely completed 7 weeks after birth, although intermittent suckling - without any substantial milk transfer - may continue for several months, especially if the mother has only one kitten. This is particularly likely to occur at times of stress and is referred to as comfort suckling.
Cats are formidable hunters and many of the motor patterns that appear will be used in catching and killing prey. Adult predatory skills are improved by early experience with prey and by observing the mother's predatory behavior when young.
Social experience in the first few weeks of life plays an important role in determining the range of stimuli that will elicit predatory behavior. In experiments performed by Kuo in the 1930s, kittens raised with rats in the same cage never killed rats of that strain when they grew up, although some would kill rats of different strains. Willingness to try new foods and preferences for particular types of food appear to be strongly determined during kittenhood, partly as a result of the queen's influence.