The boom in pet ownership in Japan has led to a new phenomenon: legions of elderly animals that doting masters pamper with fortified food and vitamins, aromatherapy and even acupuncture.

Though figures are scarce, a study published last year showed that longevity for cats in Japan almost doubled between 1991 and 2003, from 5.1 years to 9.9 years. Dog longevity surged from 8.6 years to 11.9 years.

Researchers attribute the jump to better health care, more vaccinations, a more balanced diet and a new trend of pets being allowed to live in homes — once unthinkable in a country of tatami-mat houses.

But longer lives have led to ailments seldom seen before in pets in Japan, such as cancer, diabetes, heart disease and dementia, said Hideki Hayashidani, an assistant professor at the Tokyo University of Agriculture and Technology, who carried out the longevity study.

“Japanese attitudes toward pets have changed radically. Owners dote over them like children,” Hayashidani said. “That means fewer pups and kittens die from infections, while cancer and heart disease cases have hit the roof … And owners will pay anything to keep their pets alive longer.”

Japan’s doting owners have helped push pet spending to new highs. The pet industry here topped $8.6 billion in 2005. That’s only a quarter of expenditures in the United States, but for Japan represents a 40 percent increase since 1994.

In a sign of the nation’s growing obsession with animal companions, industry figures show Japanese families now own over 23 million pet dogs and cats, exceeding the number of Japanese children under 15, which hit a new low of 17.46 million in 2006.

Japan’s aging dogs also benefit from specially designed care items such as doggie diapers, harnesses that support aging pooches on walks and pet strollers. Elderly cats have their own products, including climbing towers with extra padding.

And owners can take a break from their pets by getting a nursing care specialist. Keiko Himi, who runs the pet-sitting service “Nyan to Wonderful” northeast of Tokyo, says an increasing number of owners ask her to care for aging pets while they run errands or work.

Death doesn’t end the pampering. A spate of companies offers everything from pet cemeteries, funerals and memorials to counseling for grieving owners. Tokyo’s Japan Pet Ceremony Co. runs a 24-hour funeral hot line; the Machida Izumi Joen cemetery offers the ultimate in owner-pet companionship: a shared grave.

(毎日インタラクティブ)