But they didn't realise they had left one puppy behind -- his colouring made him blend in with the surrounding wood.
Leonel and his sister were heartbroken that the puppies were being killed.
But then they noticed that Gira kept returning to the shed, had a look and discovered the surviving puppy.
They decided to keep his existence a secret until he could open his eyes.
"We knew they wouldn't do anything to him then and that Bobi would remain with us. So we kept the secret," Leonel told AFP.
"Afterwards, we were punished, but it was worth it," he said.
Today Bobi is living out his twilight years oblivious that he is a world record holder, except for the media visits following the Guinness classification.
"We didn't expect this reaction," Leonel said.
Leonel attributes Bobi's longevity to the tranquility of country living and his human diet, which includes lots of meat and fish.
"He has always eaten what we eat," he said.
He has never been chained up or put on a leash and used to roam the woods around the village.
Today walking has become difficult, so he spends most of the time hanging out in the yard with cats or napping after meals.
Many of the Costa dogs have lived a long life. Bobi's mother Gira lived to 18 years and another dog lived to 22.
"We see situations like this as a normal result of the life they have, but Bobi is one of a kind," Leonel told Guinness.
