Japan's dogs and cats are getting older thanks to advances in veterinary medicine and the care which many people lavish on their four-legged friends, a survey said.

About half of Japan's pets are more than seven years old, which translates to 50 years old in human terms, the study by Japan's Pet Food Manufacturers Association showed.

"Balanced food, sophisticated health care services and overall attention of pet-owners to their pets have resulted in pets' longevity," said Katsuo Mochizuki, an executive officer of the association.

"Japanese people treat their pets as real family members, like feeding them the same dishes served at dinner," Mochizuki said.

The trend is in line with Japan's human population, which is rapidly graying as young people have fewer children and old people live longer.

Last week a 114-year-old Japanese woman became the world's oldest person.

With accommodation often cramped in Japan, Mochizuki said more than 80 percent of pets lived indoors, meaning fewer occasions for accidents and disease.

However, despite the lavish attention given to long-term pets, the environment ministry last year put forward a plan to encourage pet owners to take more responsibility.

The ministry said that 420,000 cats and dogs were found stray in Japan in 2005, with 90 percent of them put to death.