Farming pigs is unique compared to farming other animals in New Zealand like sheep, cattle, deer and goats. Pigs aren't primarily grazing animals. Their nutritional needs have to be provided by a balanced formulated cereal based diet. But they’re also different socially and behaviourally and have a greater need for shelter.
Around 621,000 pigs are produced in New Zealand every year, 66% in the South Island and 34% in the North Island.
To meet their needs, New Zealand's commercial pig farmers have adopted a range of farming methods that they believe best suit their animals.
There are three main styles of commercial pig farming used in New Zealand:
Indoor Many farmers prefer indoor farming because they believe it allows them to provide the best care for the modern animal by allowing them to carefully manage their environment.
During pregnancy sows are housed indoors in groups. When they give birth, they are housed individually in specialist facilities that are easy to keep clean, designed to protect piglets, and meet the different temperature requirements of the sow and her piglets.
A variety of housing systems are used to house pigs after weaning. Pigs can thrive in diverse environments which provide shelter from the elements, space, and have access to feed and water. As they grow their feed and temperature requirements are adjusted to meet their needs.
Free farmed means sows and boars live outdoors for their whole life and, are provided with shelter and protection from the elements. Sows give birth in individual huts, which they can move in and out of freely. After weaning, pigs are raised in barns on bedding.
Free range means the breeding sows and boars live outdoors for their whole life and are, provided with shelter and protection from the elements. The sows give birth in individual huts, which they can move in and out of freely. Newly weaned pigs may be kept for a short period in a fenced outdoor pen with shelter, before they are fully transitioned for rearing outdoors during the grower-finisher period.
As of 2021, approximately 55% of the commercial herd is indoors, 42% are in free farmed systems and 3% are free range.
Birthing and raising
Most indoor farmers use a farrowing pen fitted with piglet protection (farrowing crate).
This gives piglets the best chance for survival, protecting them from being crushed by their mother while allowing her to access her own feed rather than competing with other pigs.
Farrowing pens also help stockpersons interact safely with sows, which can weigh over 300kgs.
Five days before birth, a sow is moved to a farrowing crate, where she remains after giving birth for a maximum of 28 days before the piglets are weaned.
Outdoor farmers use a farrowing hut.
This individual hut allows the sow to be on her own while farrowing. The hut is designed to minimise piglet crushing and straw is provided for sow and piglet warmth and comfort.
Sows on indoor and outdoor farms give birth twice a year.