When Waitotara farmers Eileen and Danny Kavanagh discovered one of their cows with a newborn calf last month, they realised she was still in labour.
After Becky, their 7-year-old Friesian went on to produce three more babies, they wondered if the first one was really hers and they called on a vet from Livestock Improvement Corporation (LIC) to conduct a DNA test.
"Becky has never had twins before, let alone quadruplets," said Mrs Kavanagh.
This week, the Kavanaghs received confirmation that Becky is indeed the mother of all four female calves named Bonnie, Belinda, Blossom and Bluebell.
"We had Becky inseminated with sperm cells from a sire named Byreburn," Mrs Kavanagh said.