When raised in the “standard” way - close confinement, non-heritage breeds, mass-production - pigs can cause huge environmental problems.
In addition to the greenhouse gas emissions caused from their feed (which contributes up to 70% of their ghg emissions)(1), their waste can pollute rivers, streams, and drinking water with algae blooms and fish kill off (2).
When not properly managed, the inherent rooting behavior of pigs can have a similar environmental impact as tillage, destroying fungal networks and microbial communities, releasing carbon into the atmosphere (3).
However, there are lots of great things already being done to reduce the carbon foot print of raising and farming pigs. Here’s a look at what you can do to raise pigs sustainably on your farm or homestead.
Globally, 1 calorie of beef has 7 times the climate impact of pork (4), and over the last 20 years, GHG emissions from the pork industry have been reduced significantly () in both the United States and Europe.
Here are some things that you can take away from the current research and apply to your own pigs.
Integrated pasture rotation and management can lead to significant decreases in rooting behavior, and is overall better for the land and for the pigs as well (5). This is a fantastic way to farm pigs sustainably.
When pigs graze an area, perennial plants grow back with stronger root systems. Their old root systems add biomass, in the same way that no-till farmers cut back crops instead of uprooting them. This process in and of itself can help reduce the pig’s carbon footprint (5).
When we rotate pigs to different sections of land as they graze, levels of soil erosion and agricultural runoff decrease (5).
A farmer who works with the Rodale Institute suggests sowing the pig’s forage immediately after moving the pigs, so by the time they come back around to an area, the plants have grown (6).
The key to minimizing tillage and rooting is to have their pasture be abundant in food for them, and to observe when the rooting behavior starts in order to prevent it from happening as you rotate them from spot to spot (7).
It’s recommended to sow alfalfa, ladino clover, legumes, and grasses (8). Around 80% of most commercially available pig feed is cereal crops, so if you can’t plant those on your own land, the next best thing would be to source them locally and from an organic farm (9).
While you can build permanent fencing around your area with hog panel and fence posts, essentially creating different paddocks, most small farmers will work with portable electric fencing (10).
It is recommended to have piglets trained on the fence. Rodale Institute runs a hot wire at the piglets’ chin height 6 inches inside the regular fencing (10).
Having the hot wire around 6inches inside fencing is really helpful for pigs as the tend to jump forward instead of back when the come into contact with the wire, so this setup protects fencing (10).
In addition to meat, pigs also produce the valuable by-product of manure.
A study in Scotland found that replacing inorganic fertilizer with pig manure saved the equivalent of 1 metric ton of CO2/hectare (9), or around the equivalent of 2615 miles driven by your average car (11, 12). The study noted that with better training, this figure could be improved (9).
Compared to inorganic fertilizer, manure helps keep the soil pH at a more balanced level and increased total soil carbon and nitrogen. While inorganic fertilizer increases soil erosion and decreases water holding capacity, pig manure does the opposite (13).
It has also been noted that the natural behavior of pigs works their manure into the ground, helping the nutrients to be applied to the soil instead of potentially running off (14).
If your pigs are free ranging in pasture, their manure will naturally integrate into the soil and be a part of the nutrients that feed the crops that the pigs will eat in their next rotation.
If you do have an indoor area for pigs, it is essential to know a couple of things for safety. I’d recommend doing research and calling up your local extension office to learn more about how to work safely with pig manure.
First, never use the manure raw. It must be composted thoroughly at high temperatures.
Second, many sources recommend NEVER using even compost from pig manure on food crops. This recommendation is heightened for groups such as children, those who are pregnant or immunocompromised.
This discussion on the permies forum goes into more details around how to reduce risks of disease, including never feeding anything with meat to your pigs.
Again, never use raw pig manure on crops, and do your own research to come to a decision as to how you want to use it on your farm, if at all.
To raise pigs in a way that is eco friendly, it is essential to keep numbers to a reasonable amount for your land and needs, to practice pasture rotation, and to find ways to source their feed in a more sustainable way. Good pasture management will help improve the health of the soil and overall reduce the carbon impact of raising pigs.
Have a look at our full guide to eco friendly livestock for your homestead
