Bobi, the world’s oldest dog, dies at 31: A mystery unfolds

However, the database is usually based on the pet owners' self-certification, The Guardian reported. In addition, there has been scrutiny with images of Bobi in 1999, in which he has different colored paws to the dog that died in Portugal on Oct. 21, the report added. 

For a bit of background, Bobi was a purebred Rafeiro do Alentejo, a livestock guardian dog with an average life expectancy of 12-14 years, and lived a quiet life with many other animals and the Costa family in the rural village of Conqueiros in Leiria, Portugal. 

Bobi lived a good life and had never been on a leash, according to the Costa family. He was free to roam where he pleased and socialized with the other animals on the Costa family farm and only ate human food his entire life, un-seasoned. 

The Costa family maintains the integrity of Bobi's age and states his age is accurate.

Representatives from the Guinness World Record told The Guardian “it is investigating whether the claim the Portuguese mastiff lived to 31 years and 165 days is genuine.” Additionally, veterinarians in the report quoted Bobi's age as unlikely and compared the canine's longevity to a human being living to 200 years of age. 

Time will tell, the legitimacy of Bobi's legacy as the oldest dog on record, and according to reports, the next in line was an Australia’s Bluey, who died in 1939 at the age of 29 years and five months.