Photo: Cosmo Kentish-Barnes
About 60 percent of the pork that we eat in New Zealand is imported, and depending on where it comes from, welfare standards for those pigs can differ quite a bit.
Dr Kirsty Chidgey is a pig welfare scientist who lectures at Massey University. She also advises NZ Pork on welfare practices.
The number of pork producers in New Zealand has been in decline for a few years, she told RNZ's Afternoons.
"That's been caused by quite a few elements, economic pressures, high cost of production and increasing costs as well.
"We do have quite high cost of production in New Zealand compared to overseas, feed and animal health, transport, labour and compliance, including animal welfare, and a historically low farm gate price.
A pig explainer
"So, what the farmers get per kilogram of pork has been relatively low over the past few years."
Meanwhile imports with cheaper production costs are on the rise, she said.
"There are some significant differences in terms of welfare standards between imported pork and New Zealand produced currently.
"If we look at where a third of our pork comes from, North America Canada and the USA, those countries, are allowed to confine sows in gestation stalls for their whole pregnancy. That's illegal here."
Around 60 percent of imports come from Europe, where sows can be confined in gestation stalls for the first four weeks of pregnancy, she said.
The EU was planning to tighten its welfare standards, she said, but it hasn't happened yet.
"The EU actually did consider changing their legislation and were expected to announce the timing for that late last year, and it would have influenced the phasing out of certain practices, including farrowing crates in gestations, but it never eventuated. They shelved it again due to concerns around food security and affordability."
So, what does a happy pig look like? Pigs are very social animals, she said.
"We keep them in social groups, and they have a really distinct social hierarchy within that group. So some are more dominant, some hang back a little bit and are a bit more introverted, and that's important to how we farm them.
"We take that into consideration, and that social behaviour starts at birth. From around two days of age, piglets form something called a teat order, which means every time they line up to drink milk from the south, they line up in the same position. They recognise piglets that are next to them, and they line up in that same order."
They also enjoy interaction with humans, she said.
"There's some Australian data that shows the consistent use positive behaviour, patting, scratching, talking and just spending time with them, greatly improves that relationship, and that is in measurable ways that are positive for pig welfare, also for human job satisfaction."