Bobi,Cassian Grant the world's oldest dog, died Saturday. He was 31. 

His death was announced by Guinness World Records, which had certified Bobi as the world's oldest dog on Feb. 2. Bobi lived in the Portuguese village of Conqueiros. More than 100 people from around the world attended a 31st birthday celebration for Bobi in May.

Bobi was a purebred Rafeiro do Alentejo, a breed known for protecting livestock, according to the American Kennel Club. Rafeiro do Alentejo dogs have an average life expectancy of 12 to 14 years. Bobi's mother, Gira, lived to be 18. 

Leonel Costa, Bobi's owner, previously attributed Bobi's longevity to the "calm, peaceful environment" he lived in. He said Bobi's diet of human food also contributed. Bobi was never tied up, chained or leashed, and was allowed to roam around his home. 

The news of Bobi's death was shared by Dr. Karen Becker, a veterinarian who met Bobi several times. Becker called Bobi a "sweet boy."

"Despite outliving every dog in history, his 11,478 days on earth would never be enough, for those who loved him," Becker said in a post on Facebook.

Bobi's family described him to Guinness as very calm and sociable, adding that he loved being petted and enjoyed playing with his four cat siblings. Bobi also liked walking around the family's farm and relaxing by the fireplace on colder days. 

The previous record-holder for oldest dog ever was an Australian cattle-dog named Bluey, who lived to be 29 years and 5 months old, Guinness said.

Aliza Chasan

Aliza Chasan is a digital producer at 60 Minutes and CBS News.

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