Bobi the Portuguese mastiff, who had comfortably clinched the title of the oldest dog ever by the time he died last October at the apparent age of 31, is having the distinction reviewed after doubts about his lifespan gave officials at Guinness World Records (GWR) paws for thought. The canine’s demise made headlines around the globe and prompted a tribute from GWR, which declared him both the world’s oldest living dog and the oldest dog ever in February 2023. Until Bobi’s death at the age of 31 years and five months, the most ancient recorded dog was Bluey, an Australian cattle dog who died in 1939 aged 29 years and five months. However, the tributes were swiftly followed by scrutiny and suspicions about Bobi’s record-breaking age, which equates to more than 200 human years. Some observers noted that images of Bobi in 1999 showed he had different-coloured paws to the dog that died in Portugal on 21 October 2023, while vets pointed out that although his age had been registered on the national pet database, such entries were usually based on owners’ self-certification. And then there was the genetic testing, which confirmed he was old but did not provide a precise age. Danny Chambers, a vet and council member of the Royal College of Veterinary Surgeons, which represents 18,000 vets, said “not a single one of my veterinary colleagues believe Bobi was actually 31 years old”. A “totally serious” investigation by the technology magazine Wired then established that while the Portuguese government database for the registration of cats and dogs had an entry for Bobi – who was described by his owner as having been born in 1992 – it had “no registration or data that can confirm or deny this statement”. An official at the government database also told the magazine that they had never been contacted by GWR to verify the information. Bobi’s owner, Leonel Costa, did not respond to Wired’s questions. On Tuesday, a spokesperson for GWR confirmed a “formal review” of the oldest dog record was under way and that the organisation was examining the evidence and consulting experts. “While our review is ongoing, we have decided to temporarily pause applications on both the record titles for oldest dog living and ever until all of our findings are in place and have been communicated,” the spokesperson said. She added that it would be misleading to suggest that Bobi had been stripped of his title as “no action has been taken in relation to any record holders yet”. A diminutive contender named Spike briefly held the title of world’s oldest living dog before his Portuguese rival appeared on the record scene. The chihuahua – who is 22.86cm tall (9in) and weighs 5.85kg (12.9lb) – was declared the world’s oldest living dog on 7 December 2022 aged 23 years and seven days.