Adult cats 7+ years of age with an indoor lifestyle.

Kittens and older cats tend to sleep more than the average-aged adult cat.
The second questionnaire, administered 6–12 months after the adoption, was completed by 70% (266/382) of the enrolled adopters; 164 out of 248 adult cat adopters (66%), 97 out of 134 kitten adopters (73%) and five out of seven adopters for which the cat age group adopted was unknown (71%). The second questionnaire was completed online by 210 respondents and through a telephone interview by 56. Reasons that were given for not completing the second questionnaire were that no or incorrect contact details (six respondents), the adopter no longer wanted to participate or was unable to participate (five respondents) and the adopter could not be contacted within the study time frame (105 respondents). Of the 389 cats enrolled at adoption, second questionnaires were completed for 271 cats; 68% of adult cats (168/248), 73% of kittens (98/134) and 71% of cats for which the cat age group was unknown (5/7). Those cats for which the cat age group information was unavailable were excluded from the reporting of the adoption outcomes by age group, leaving responses available for 168 adult cats and 98 kittens. Of the responses for adult cats, 157 had adoption price information. Those cats for which the adoption price information was unavailable were excluded from the reporting of the adoption outcomes by adoption price group, leaving responses available for 138 adult cats in the AUD$20 group and 19 in the ≥AUD$99 group.
The beginning of the second stage of development is indicated by the emergence of adult teeth:
If you rescue/adopt an altered (spayed/neutered) adult with an unknown vaccine history, I strongly suggest running a titer for panleukopenia (not herpes or calici) rather than vaccinating blindly. If the cat is spayed or neutered, chances are she or he was vaccinated as a kitten. However, the age at which they received their last kitten vaccine (past 16 weeks of age?) will not be known so the decision to administer a vaccine, or not, is a judgment call. This is a situation where titer testing can help out. At what age to Kittens become May 2, 2017 - Life Stages of Cat Years: Adult, aka Maintenance Years ..At this age kittens are behaving and using their body language like adult cats.
Remember that need different nutrition than younger adult cats, too. Once your cat is older than 7 years old, you should switch her to a food that has been formulated for older pets (look for something like “mature adult” on the label). Cats that are older than 11 years old also have special nutrition needs. When your cat reaches this age, you should switch her to a food formulated for older adult cats (look for “senior” on the label).Kittens require more food per pound of body weight to support their growth than do adult cats, and therefore should be fed more often throughout the day. "Growing kittens up to six months of age may require three meals a day," says Francis Kallfelz, DVM, Ph.D., board certified by the American College of Veterinary Nutrition and James Law professor of nutrition at Cornell University College of Veterinary Medicine. "From age six months to maturity, most cats will do well when fed two times a day."Look for a food that has an AAFCO statement, similar to this: “Animal feeding tests using AAFCO procedures substantiate that (this food) provides complete and balanced nutrition for maintenance of adult cats.” AAFCO stands for the Association of American Feed Control Officials. In addition to setting guidelines for nutrition labeling on pet food, this group also helps to determine what nutritional guidelines must be met in pet foods. Look for a food that has undergone animal feeding tests – this means that this food has undergone feeding trials and meets the nutritional and calorie needs of an animal in this life stage.Cats are considered to be adults by the time they are 1 year old. It is not uncommon for them to live up to 20 years or longer. Once they reach 7 or 8 years of age, however, cats are considered to be “senior citizens,” and age-related diseases and metabolic changes begin to emerge. The time between kittenhood and the senior years is young adulthood, and it is important to recognize the feeding goals and nutritional priorities of this life stage.