In many animals, sleeping excessively can be a sign of some disease, stress or depression, but with cats, that is not the case.
Biologists say this habit of cats comes from two things. The first is their protein-rich diet, which needs long hours of rest to be fully digested. The second is their crepuscular predatory pattern, according to veetstreet.com.
Crepuscular creatures are those that are most active at dawn and dusk. Creatures with a crepuscular predatory pattern mostly hunt during dawn and dusk and rest in between.
According to experts, cats sleep around 15 hours a day and you need not be worried until and unless you notice a stark difference in the timing. You should also keep in mind that kittens and seniors tend to sleep more, around 18 hours a day.
Breed, temperament, and health are also a few factors that determine a cat's sleeping pattern. These felines also tend to sleep more in winter, especially if they have a warm cozy place to snuggle.
The American Association of Feline Practitioners and Boehringer Ingelheim Vetmedica urge cat parents to keep a track of their pets' sleeping pattern. During usual catnapping, a cat should be able to quickly react to stimuli, such as other people walking into the room or cat food being prepared.
However, if your cat is sleeping outside its pattern or having difficulty getting up or lying down, it is advised that you quickly visit the vet.