Glenice Bagley, 69, of Widnes, England, said she obtained the sheepdog-Alsatian mix, Sheba, in 1987 when the dog was already 3-years-old, putting her at an older age than the current 23-year-old record holder in Italy, The Sun reported Monday.
Bagley said Sheba's age was verified by a veterinarian when she went in for an ear operation nine years ago.
A Guinness spokesman said the organization requires numerous forms of verification for oldest dog records.
"As part of the verification process we would require a vet's statement and we try to piece the history of the owner and their dog -- including photos of them down the years."
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