PIGS
KEY TAKEAWAYS
PIGS
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Locally sourced feed, feed from crop residues, permissible food surplus, and feed grown on-farm are all great alternatives.
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In the UK, Organic guarantees that the pigs are ‘outdoor reared’ with access to straw bedded shelter and big paddocks.
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Pigs integrate well into arable crop rotations and woodland mob grazing systems, and can get a substantial amount of their diet from pasture.
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Don’t be shy about asking your suppliers what feed they use. By showing interest and offering support, you can help encourage suppliers to adopt more sustainable feeding practices.
Pigs Deep Dive
Image Credit: @hegnsholt farm in Denmark
Pigs are monogastric (they only have one stomach) so direct GHG emissions from the animals themselves are not the main environmental impact to consider. Instead, the trickiest challenge with pigs is how farmers feed them without importing large quantities of feed (usually soy, wheat, barley and maize) from other countries.
It’s all about the feed
Imported feed has hidden land use impacts including the pollution and emissions tied to deforestation and the use of nitrogen fertiliser. Over three quarters of the carbon footprint of British pork is tied in with feed production.
Pigs are omnivores; they evolved from wild boar, whose varied diet as both foragers and scavengers includes roots, tubers, berries, leaves, twigs, fish, birds, carrion, eggs and more. This means that pigs can eat food waste. Historically, their role in agriculture was to recycle both kitchen leftovers and crop residues back into a human food source (i.e. pork). Now, arable crops that could be directly fed to people are instead diverted into pig feed on a global scale. This is a massively inefficient use of land and an element of the industrialised food system that has been robustly criticised.
Food waste for pigs
The historic practice of feeding pigs swill (food waste mixed with water) has been banned for 20+ years (unless it can be guaranteed that the swill hasn’t come into contact with any meat). This ban was in reaction to the outbreak of Foot and Mouth disease in the UK in 2001, which was caused by poorly cooked swill contaminated with illegally imported meat that was infected with the virus.
In 2013, the environmental campaign group Feedback launched a campaign called The Pig Idea to push for a change in the law and allow for catering waste to be used for animal feed again. They argued that a safe, well-regulated swill processing system, like those in place in Japan and Korea, should be introduced to the UK. Swill is half the price of imported feed, and studies suggest that this system could reduce the land use of pork in the EU by one-fifth.
The Sustainable Food Trust advocates for this too in ‘A Return to Swill for Human and Plentary Health’. Until swill is re-allowed, agroecological farms must find other sustainable ways to wean themself (and their pigs) off of feed imports.
Pig farming practices to look out for include:
Grazing pigs on herbal leys and diverse pastures
Growing pig feed and forage on the farm (or mixing it from local sources)
Rotating pigs around a veg farm’s fields after harvest to forage crop residues
Mob grazing pigs in woodland conservation systems
Using food waste from manufacturing processes, such as brewers grain (still permissible in UK law)
Examples of all of these farming practices can be found at The Wooly Pig Company, Gothenly Farm, Lynbreck, Pipers Farm and Redwoods Farm.
Amy at Redwoods Farm worked with local farmers to create a soy-free feed for her pigs, paving an agroecological path forward for pig farming
Manure and the environment
After feed, studies show the mismanagement of manure has the most significant environmental impacts in pig farming. Acidification (release of acidic gases risking formation of acid rain) and eutrophication (over enrichment of nutrients in ecological systems) pollute and degrade land and waterways.
Agroecological farms such as those highlighted are actively working on ways of not overloading their land with manure. They constantly monitor the environment for signs that stocking density is too high and adjust before these issues manifest.
The Woolly Pig Company - Farm Highlight
The Woolly Pig Company is a pig farming project in Dalry, Ayrshire, Scotland. It combines a pork enterprise and woodland restoration work. The sale of meat (60-80 pigs per year) pays the wage of a conservationist, David, who manages Brodoclea, a 430 acre site.
The pigs are a breed called Mangalitza which has a woolly coat and a longer snout for foraging, and is hardy enough to be kept outdoors in Scotland all year round. The pigs' varied woodland diet, slow raising (1 year 6-8 months), and active outdoor lifestyle result in deeply flavoured, moist meat that may require slightly different cooking methods than typical pork.
The big question about feed is easy for David to answer because the conservation-grazing model at Brodoclea means that “only 3% of the [pigs] diet in the summer is feed. In the winter, the feed goes up to 25% of their overall diet and then for the last 4 weeks of their life they are ‘finished’ on 45% feed.” The feed he uses is sourced agroecologically. It was co-created with Campbells, a local feed producer, and is a mixture of legally permissible food wastes from manufacturing processes (e.g. distillers grain and molasses).
The only unsustainable aspect of the pigs’ diet is the sow rolls fed to pregnant pigs for two months which contain 2% GMA Soya. This is a tiny proportion of overall feed at Woolly Pig Company, but David is still hoping for a more regenerative option someday.
David rotationally mob grazes 160 Mangalitzas in five groups across 20 woodland sections, allowing brief disruption followed by long rest periods, promoting biodiversity. The pigs' rooting and trampling create water-holding scrapes, open space for diverse seeds, and help spread species across the site. Without them, bracken would dominate, and surveys show higher biodiversity in the areas grazed by pigs.
Finally, the Woolly Pig Company fosters community engagement by creating public walkways, offering site tours, and collaborating with local services to support land access and opportunities for local residents.
Animal Welfare
Animal welfare is also a main driver in concerns about pig farming practices. Asking questions about the way the animals you are eating have been treated is also a huge part of the agroecological puzzle.
If you can’t source your meat from the kind of agroecological farms we’re suggesting, then start by asking your suppliers appropriate questions about how they house (indoors vs. outdoors) and feed their pigs (UK or EU grain has lower deforestation risk), how they manage manure and how much space the pigs have .
If you cannot purchase organic, look for “outdoor bred” or “outdoor reared”
If your only option is to buy indoor reared look for 'straw bedded' or 'deep bedded' (straw is warm but also ensures that pigs exhibit natural rooting behaviour, without which they would bite each others tails in boredom, leading to painful tail docking practices)
The good news is that pig farming in the UK has improved relatively in terms of environmental impact. This is mainly due to the changing composition of feed, which just goes to show – asking your supplier questions about feed is a good place to start!
Consider buying direct from a local farmer. Show them what you want as a customer (soy-free, pasture raised) and that you are willing to go on the journey with them in both a socially and environmentally supportive way.
Gothelney Farm
- Farm Highlight
The Pigs at Gothelney Farm are slow growing breeds: either Tamworth or Large Black crossed with Saddleback or Duroc. These breeds are chosen because they can feed by grazing, but also put on enough weight in 10 months that the cost of growing them meets the price that their meat can be sold for.
They are “forage fed” on herbal leys in the summer or longer-term cover crops in the winter, making up 75% of their diet. The final 25% is an intercropped mix of farm-grown oats, peas and barley, grown alongside wheat. The pigs are finished in a roundhouse.
The whole idea is that they are integrated into the farm’s arable system: it’s a pigs and wheat pairing. The pig’s manure reduces the need for fertilising inputs and their pork makes it financially viable to have longer rotations with multiple years of rest for the soil.
The only time that Fred Price, the farmer, needs to buy in feed is for the weaner pigs, whose feed is supplemented with organic soya grown in the EU. However, the farm’s goal is to be 100% forage-fed at every stage of the pig’s life.
Grazing pigs on diverse herbal leys from April to October reduces the need for medical intervention while supporting both pig health and soil biology.