An animal welfare group has released 360° footage of pigs in farrowing crates in a bid to end their use.
Save Animals From Exploitation (SAFE) is calling for a national ban on farrowing crates, calling them cruel and inhumane.
SAFE campaigns director Mandy Carter said sows were placed in farrowing crates straight after giving birth.
She said pigs were highly intelligent animals and it was frustrating for them to be enclosed in cages.
"The problem with farrowing crates is that we are sticking animals in cages so small that they can't even turn around and they're in these cages for four to five weeks at a time," she said.
"We wouldn't do this to a dog, there would be a massive outcry if we were to do that so... why would we do it to farm animals?"
Ms Carter said the footage was secretly filmed on a pig factory farm in the Waikato this year.
She said it's time that farrowing crates are banned.
"30 percent of New Zealand farmers are already not using farrowing crates and even the government's national advisory committee has said that farrowing crates should be phased out, but there is no economic alternative at the moment," she said.
"It actually boils down to money, it's for profit for the pig industry that they're still keeping sows in these terrible conditions."
Ms Carter said countries like Sweden, Switzerland and Norway had already banned farrowing crates.
She hoped the newly released footage would educate the public and prompt them to support SAFE's campaign.
"Until now, we've just shown people, here's some pig footage, you can't really feel... what it must be like to be one of those pigs," she said.
The Ministry for Primary Industries said an independent review of the crates by the National Animal Welfare Advisory Committee (NAWAC) in 2016 found there were no practical alternatives.
Julie Collins, the Director of Biosecurity and Animal Welfare, said the Ministry continues to look into other ways of caring for sows and their piglets.
She said there were already new regulations that were announced last week to protect the welfare of pigs, on a list of 46 regulations for several animals the Ministry had decided to enforce.
"There are six regulations, they look at the size of the crate to make sure they are appropiate, they look at making sure there are dry lining areas for pigs and they also look at rules around tail docking and castration," she said.
The New Zealand Pork Industry Board said it was always considering other alternatives to best care for their animals but it stands by NAWAC's decision that farrowing crates are currently the best practice.
The board's chairman Ian Carter disagrees with SAFE's call for a nationwide ban.
"I think it's inappropiate because we need to look after animals and certainly the newborn piglets, so it's [the ban] not consistent with what's best for our animals," he said.