Mike King's manager sought thousands of dollars from the Pork Board after the comedian was dropped from its television campaign - and after King had been alerted to pig-farming concerns.

Documents show King's manager was corresponding with the Pork Board as late as March, just two months before the screening of last weekend's Sunday documentary, in which King turned on his former employer and exposed what he called "callous" and "evil" pig-farming conditions.

King says he knows nothing about his manager's request for compensation. But the Pork Board is now going on the front foot against its former frontman, claiming that it had previously discussed pig-farming issues with him.

King denies this, saying he was first alerted to concerns after a conversation with a friend in Invercargill last November, and after that the friend sent him a link to an internet video clip showing distressed pigs.

King's contract with the Pork Board, which had been rolled over annually since 2002, was not renewed last December.

A letter to King from Pork Board executives on March 16 thanks him for his services and their "mutually beneficial relationship", but rejects a suggestion from King's manager, David Steele, of a severance payment.

Steele wrote back to the board on the same day, saying he "never asked for a severance payment".

"What I suggested was that in light of the very late notice given to Mike and the fact that his image was still being used extensively around the country on pork posters and recipes, that he was entitled to some recompense."

Pork Board executives say the figure of around $50,000 was raised in a telephone conversation between Steele and its marketing manager Hadleigh Smith.

The request went to the board in February, and was rejected.

King said his manager's request for recompense was "news to me" and asked who had told the Herald on Sunday about it.

"I don't want their money."

Although his contract expired in December, he said he had not received any money from the Pork Board since he saw the internet video in November.

Steele told the Herald on Sunday that King had no knowledge of his request for recompense.

"I was coming from a purely commercial angle. It was purely coming from 'you have only given us three weeks' notice and Mike's brand is still out there, so if you were going to do this, you could have given us a bit more notice'.

"There were still butcher shops who had his recipes lying around, posters lying around."

King said he had no issue with the board dropping him. "There's all sorts of nonsense that this is Mike King getting back at the Pork Board. It was not an attack on the Pork Board. I applaud them for trying to make changes before they legally have to.

"The farmer has not broken the law. [Animal welfare group] SAFE told me the minister has the power to change legislation this year - the anger should be turned at the minister. The people's wishes are that crate farming be outlawed."

On Friday, animal welfare regulators announced a lengthy review of the use of sow crates on pig farms. Last weekend's Sunday documentary showed King sneaking into a pig farm, and being alarmed at the scene he confronted - distressed, injured and squealing pigs confined to spaces where they could barely move.

The farm at the centre of the saga was later inspected by officials, but is not believed to have broken any laws.

NZ Pork chief executive Sam McIvor said King's actions last weekend were "very disappointing and hard to understand".

Board chairman Chris Trengrove: "We were gutted about it." He believed the industry had been unfairly misrepresented and harmed.

Former Pork Board chief executive Angus Davidson - the man in charge when King was hired - believed publicity about pig-farming was "unavoidable" over the past few years. He believed he had discussed the subject with King.

But King was adamant that he had received no information from the Pork Board before signing the contract in 2002. The first he knew was when he received his friend's email and internet link last November. "As soon as I found out, I did something about it. I am giving my time and I have not received any money since I found out - end of story."

"I find it ironic that [media commentators] can sit from their lofty mountains and say 'shame on Mike King'. Well I say 'shame on you'. You claim to have known about this, you claim to have known about this for years and you had the power to change it but you sat there and did nothing and now they criticise me?"