The world’s first set of identical twin puppies has been born and confirmed to be monozygotic, as published in the journal Reproduction in Domestic Animals.
A veterinarian in South Africa’s Mogale City, Kurt de Cramer, made the discovery as he was performing a C-section on an Irish Wolfhound. The pregnant dog was giving birth to a litter of seven, but unlike most canine pregnancies, this one produced an unprecedented irregularity.
While there were seven puppies, there were only six placentas. Two male pups were sharing one.
Inside, each of the two puppies had their umbilical cords hooked up to their shared placenta for them to receive nourishment from their mother.
When the vet looked at both male puppies once born, it appeared they were indeed identical twins. Tests in their early stages confirmed as such, which provided the green light needed for the scientific community to declare the pups, Cullen and Romulus, the first monozygotic twins the world has ever been able to confirm.
As of now, the genetic occurrence of twinning extends to three species on Earth, that we know of: dogs, humans, and the nine-banded armadillo.