A police spokesman confirmed the owner of the dogs would be charged with growing cannabis and possession of explosives - ammunition. It is understood the man did not have a firearms licence.
The spokesman said all charges were made after police were called to the Gisborne house over the attack.
He would also be charged with owning a dog that causes injury, and at least three of the four dogs had been ordered to be put down.
The owner earlier said he was "shattered" by what happened.
The man, who considers himself a grandfather to the injured 5-year-old, Calais, said he was going to hospital to visit the youngster for the first time later today.
"We're pretty shattered, but he's all right," the man said.
"It'll be hard to see him like that."
He had not yet spoken to Calais' mother, but said his partner had told him she understood what had happened was just an accident.
"His mum's being real good about it."
Gisborne hospital confirmed Calais was in a stable condition on Monday morning.