Mariah Carey spends £28,000-a year grooming her dogs.

The '#Beautiful' hitmaker - who is worth around £290 million - regularly pampers her eight pet pooches by booking them into canine salons and paying for them to have the best animal treatments on the market.

A source told the Daily Mirror newspaper: ''Mariah pays for all the spa therapies herself and doesn't expect any special treatment. Only her dogs get that.

''While prices start at £40 for a simple trim, other treatments are extra and Mariah's dogs really seem to enjoy their wraps and full body massages.

''She pays for her doggies to travel with her first class on a whim. And when they can't she will check them into doggy day care at salons Chateau Marmutt, Barkingham Palace or Pour La Pooch. She also employs a designated chauffeur to ferry them to and from at around £400 a time.''

Mariah likes her four-legged friends to have the popular blueberry facial, which originates in Los Angeles, because it exfoliates their coats and reduces staining.

The source explained: ''She will always get the animals groomed before travelling - she likes them smart at all times. As well having them bathed and blow dried, Mariah is also very keen on the latest LA trend for canines - blueberry facials.''

Mariah - who has two-year-old twins, Moroccan and Monroe, with her husband Nick Cannon - is ''obsessed'' with the way her dogs smell following their treatments and is delighted they help reduce wrinkles.