A new study involving more than 19 million cats from across Canada and the United States suggests most of the animals continue to put on weight after they reach adulthood, and their heaviest weight is higher now than it was two decades ago.
Researchers at the Ontario Veterinary College at the University of Guelph analyzed 54 million weight measurements taken at vet offices between 1981 and mid-2016 to get a sense of the typical weight gain and loss pattern over the course of a cat's life.
They say the study, published in the Journal of the American Veterinary Medical Association this week, is the first of its kind to use such a large pool of data.
Overall, the data showed cats' mean weight reached its peak between six and 10 years of age for the most common purebred breeds, Siamese, Persian, Himalayan and Maine Coon and at eight for domestic cats.
Male cats generally hit higher weight peaks than female cats, and cats that were spayed or neutered tended to be heavier than those that weren't.
The findings showed a difference of about one kilogram between age one and the peak. As well, the mean weight of neutered, eight-year-old domestic cats rose about 1/4 of a kilogram between 1995 and 2005 and then remained steady for the next decade.