Graphic footage of pigs being kicked, beaten and ridden while being artificially inseminated, allegedly taken at a piggery north of Adelaide, has been released by an animal rights group.

Key points: Animal Liberation NSW says footage of animals being abused at a piggery was anonymously sent to them

Animal Liberation NSW says footage of animals being abused at a piggery was anonymously sent to them RSPCA South Australia confirms investigation underway into practices at an SA piggery

RSPCA South Australia confirms investigation underway into practices at an SA piggery Cruelty is 'standard industry practice', Animal Liberation spokeswoman says

RSPCA South Australia confirmed an investigation was underway into practices at the piggery.

Animal Liberation New South Wales said the footage was anonymously sent to them after cameras were secretly installed inside the piggery.

The group's campaign director, Emma Hurst, said the footage, which the ABC has viewed, showed workers kicking the pigs, beating them with paddles and riding them while they were being artificially inseminated.

"It just looks absolutely horrendous, it looks like hell on earth," she said.

"There's sick and dying pigs inside the shed, there's pigs that can't stand on all of their legs.

"There's footage of piglets being mutilated without pain relief, having their ears clipped, and there's footage of pigs ripped into various pieces scattered all over the floor."

Ms Hurst said sick and injured pigs were dumped in a pile of decomposing carcasses.

"There is footage of outdoor pits filled with pigs and piglets; it looks like almost 100 pigs in these pits," she said.

"They have obviously been shot in the head. Some of them look like they have had their throats slit open."

Sow 'found starving in pool of urine and faeces'

Ms Hurst said the RSPCA had rescued a starving sow from the piggery that had allegedly been left in a pool of urine and faeces for at least two days after falling into the waste pit.

"Footage taken the following day reveals workers had made no attempt to save her," she said.

"If it weren't for investigators contacting the RSPCA, she would have starved to death."

In a statement, the RSPCA said it had previously attended the piggery and that newly released footage was being reviewed as part of an ongoing investigation.

But Ms Hurst said she doubted an investigation would result in any charges being laid.

"We think a prosecution is unlikely because a lot of the cruelty that we are seeing is standard industry practice," Ms Hurst said.

"We are seeing footage like this come through every few weeks to every few months for the last few years.

"This certainly seems to be something that is industry wide. It's not just a rogue operator that's operating this way, it's something endemic in the industry, really."

The owner of the piggery has been contacted for comment along with the organisation that oversees the pork industry, Australian Pork Limited.