how old is the oldest cow
O'Leary bought Big Bertha (a Dremon) as a 2-year-old for $14 at a fair in 1946. Big Bertha was not only listed in the Guinness Book of Records as the world's oldest cow (49 years, nine months) when she passed away the day after Christmas, 1993, she's also listed as the world's most productive, having 39 calves. At last report, two of those calves remained in O'Leary's herd. One is 35 years old, the other a mere 30. World's Oldest Cow Still Hard At Work AG WORLD Ag World 20-1-22 It's been just over two years since the world's oldest cow moved on to the big pasture in the sky. But Big Bertha's hardly been forgotten around Blackwatersbridge, County Kerry, Ireland.