Japan's first elderly care home for dogs is set to open this week, tapping into a growing market as the problem of ageing spreads from humans to the pet population.

Saradi Corp. will accommodate up to 20 dogs at a facility set up in cooperation with a veterinary surgeon in the resort area of Nasu, north of Tokyo, Chief Executive Nana Uchida said on Thursday.

A veterinarian will be on call 24 hours a day and the dogs will have the opportunity to exercise, eat natural foods and mix with younger dogs to maintain their vitality, the company said in a statement.

"We see a strong demand for these services, partly because owners are ageing alongside their dogs and also because many women work nowadays, leaving them no time to care for their dogs," Uchida said in an interview.

Many owners find it hard to cope with symptoms of ageing in their pets, such as constant night-time barking, the company said.

Fees will be around 100,000 yen ($815) per dog per month.

Japan is the world's fastest-ageing nation, with 40 percent of the population expected to be over 65 by 2055.

The average lifespan of the country's 13 million dogs has also extended from five years or less in the 1980s to 15 years or more recently, thanks to improved diet and medical care, the company said.