The female calf was born with the extra appendage on its back March 9 on the Brenham-area ranch of Charles and Karen Harmel, the Houston Chronicle reported.
"I've never seen this before," said Dr. Lee Panko, who removed the leg Tuesday. "I think the calf developed that way from a genetic defect."
The extra leg, similar to the calf's front legs, was attached just behind the shoulder but was not connected to the spine, KWTX-TV, Waco, reported. The young bovine was sent home with the Harmels later the same day.
Charles Harmel, who has been raising cattle for about 40 years, said it was a first for him as well. The calf was born in the middle of the night and at first he and his son didn't notice anything amiss.
"We went back down to check it about 30 minutes later and my son said, 'What's that on the back of that calf?'" Hamel said.