'It's just bad luck': Cause of 'miracle' calf's extra limb explained

Eyebrows have been raised after a photo of what appears to be a calf born with an extra leg was shared online.

Melissa Culverson, who posted the photo on a Facebook group, described the animal as a “drought miracle calf”.

The image shows the calf standing in a paddock in the drought-affected Central West region of New South Wales with an extra limb protruding from its upper body.

Coming from the animal’s side just above its functional front left leg is a fifth leg complete with a hoof and what appears to be a regular fetlock joint.

The baby cow looked to be otherwise in perfectly healthy condition.

Ian Bradshaw, from Cattle Vet Services, told Yahoo News Australia the phenomenon was not as uncommon as some might think.

“This is a condition called polymelia or developmental duplication and is a not uncommon birth defect in cattle,” Dr Bradshaw said.

“It is known to be caused by a recessive gene and the appearance of the extra limb around the shoulder area is the most common presentation.”

Dr Bradshaw added the animal in the photo was unlikely to suffer negatively if the limb was left attached.

“But it can be surgically removed, usually with minimal problems,” he said.

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Stefan Kurys-Romer, from Naturaliste Veterinary Services, also told Yahoo News Australia the occurrence was well documented throughout history and could be put down to an abnormality in the womb.

“It’s just bad luck. Something goes wrong in the reproductive process in the embryology,” Dr Kurys-Romer said.

“It’s accepted that it is quite random. I’ve seen it happen everywhere.”

Dr Kurys-Romer dismissed the theory of a stronger foetus consuming its weaker counterpart in the womb, resulting in duplicate limbs in birth.

Others commented on the Facebook post sharing their anecdotes from their own experiences of seeing farm animals with extra body parts.

“I saw a similar one a few years ago doing a stock truck rollover. It was full grown and came running out. Everyone stopped to check it out,” one person wrote.

“I’ve seen that happen to sheep and another one had an extra tail hanging on its back,” another shared.

“We had a similar one many years ago, is part of the Angus genetics from what our vet told us. Had quite a few with varying deformities over two years,” a third added.

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