noxious - injurious to physical or mental health; noxious chemical wastes; noxious ideas. harmful - causing or capable of causing harm; too much sun is harmful to the skin; harmful effects of smoking.
Newborn kittens, also sleep more -- upwards of 16 hours a day. Although newborns sleep a lot, it generally isn't continuous. Newborn kittens take frequent naps which often last for mere minutes at a time. Young cats usually develop their sleeping behaviors once they're around three months in age.
These are the times a cat in the wild would tend to hunt. Your cat's age greatly affects his activity level. Young kittens, under 1 year old, tend to sleep more than adult cats while they are still growing. Newborn kittens actually sleep most of the day for their first few weeks of life. Senior cats, over 7 years old, slow down and sleep more than their younger counterparts. Conditions like arthritis and other joint issues tend to impair your older cat's mobility, making him more apt to sleep for a longer period of time.