The man, from the village of Pinell de Brai in Tarragona, was cycling down a country lane when the pack jumped on him and pulled him off his bike.
They then proceeded to bite him on his arms, legs and back, until their owner, who was approximately 100 metres away and witnessing the attack, blew a horn to call them back.
Instead of running to the victim's aid, the local hunter took off without even calling the emergency services.
The victim, who was left seriously injured by the mauling, called his brother to explain where he was and what had happened.
He in turn called an ambulance to help him with the rescue but it ended up taking them an hour to find the 41 year old, who was lying in a pool of blood camouflaged by the high grass of the area.
When he reached the hospital, the man required a blood transfusion prior to undergoing two surgical operations, the first one lasting four hours.
Local police have since identified the dog's owner and are investigating whether he is guilty of grievous bodily harm and failing to call for help.
The accused claims he didn't approach the victim to prevent the dogs' hunting instinct from kicking in even further in his presence, a theory held up by other hunters according to Catalan daily La Vanguardia.
Spanish news agency EFE reported the man and his dogs already have a record of attacks but never of the same severity.