A Northland man who admitted bashing a puppy eight times on the head with a hammer has been jailed for two years and five months.

Hanuere Paul Witehira, of Kaikohe, had been drinking when he arrived home around noon on July 9 and became angry with his teenage son when the food he wanted for lunch wasn't in the house.

He told his son, "I'm going to kill your dog", got a hammer from his bedroom, then went outside where the five-month-old puppy, named Valley, was tied up.

During sentencing in the Kaikohe District Court Judge Greg Davis said the blows left the puppy with skull fractures, swelling to the brain, bruised eyes and broken teeth.

It was also bleeding heavily from the nose and mouth.

Police took the puppy to Bay of Islands vets but its injuries were so severe it had to be put down.

At the time police said the puppy's howls could be heard as far away as their station, two blocks away, and prompted a flurry of calls from neighbours.

Witehira was charged with wilful ill-treatment of an animal and denied bail. At the time he was on bail for driving with excess breath alcohol and driving while disqualified.

He was sentenced on all three charges when he appeared in court Wednesday. He looked much older than his 53 years with long grey hair and his one eye darting around the courtroom.

Judge Davis said the attack would have caused significant pain and distress to the puppy, and must have been horrific for his son to witness.

There was also a sadistic element in that it was a form of punishment directed at his son.

In a victim impact statement read to the court by Judge Davis, the son said he was "really sad" his father had killed his dog. Alcohol had played a part and his father was hard to be around when he drank.

The son feared he had made the situation worse by calling the police but he could not stand by and let his dog be killed.

He was also worried about how his relationship with his father would develop in the years ahead.

Witehira interjected at that point, saying: "I love my son".

Through his lawyer, Hiku Taylor, Witehira said he believed the puppy was sickly and not being looked after properly.

He was afraid it was going to infect his grandchildren but couldn't afford to take it to a vet. He admitted, however, he had gone about it the wrong way.

The driving charges arose when he was pulled over while riding a motorcycle on Hillcrest Rd on May 4. He admitted he had been drinking and blew an alcohol level of 678 micrograms per litre of breath. The limit is 250mcg.

It was his eight drink-driving conviction and his 11th of driving while disqualified. He was disqualified indefinitely in 1999.

Judge Davis said he had to send a message to Witehira, and to the public, that such cruelty would not be tolerated.

He took 30 months' jail as a starting point for the animal cruelty charge and 14 months for the driving charges, reducing the term for his early guilty plea and health problems including a badly healed broken leg and "gastro-intestinal issues".

The end sentence was two years for animal cruelty and five months for the driving offences, to be served cumulatively.