Study Shows Pig Farmers Improving Their Environmental Footprint Through Efficiencies

Three pigs grazing in a grassy valley with a mountain range in the background.

Photo by Sergio

DES MOINES, IOWA – Oct. 15, 2019 – A new environmental study has found that pig farms are generating less manure nutrient content associated with odor. Data gathered from more than 106,000 samples at 182 North Carolina farms shows significant reductions in ammonia levels and manure nutrient content. The improvements are attributed to gains in feed efficiency, which means it takes less feed to raise a pig.

“For an industry that is continually striving to become more sustainable, this study shows that pig farmers are making significant progress toward reducing the environmental impact of their farms,” said Lowry Harper, president of Harper Consulting, who conducted the study from decades-long data.

The study, funded by the Pork Checkoff and conducted by Harper Consulting in consultation with Southern Utah University, found that North Carolina pig farmers have significantly increased feed efficiency over the past 17 years. Long-term, continuous improvement has resulted in trending reductions in nutrient content in manure lagoons at the farms. Specifically, data gathered from more than 106,000 samples at the 182 participating North Carolina pig farms showed a reduction of 35% to 78% in the nutrient content from hog finishers in primary lagoons, and a reduction of 17% to 68% in primary lagoons for sow farms. Also, the study showed a reduction of 22% to 54% in ammonia levels.

The analysis showed considerable improvements in pig farms’ nutrient output, with major decreases in all nutrient concentrations, except for copper which is an essential dietary nutrient. The modeling conducted suggested decreased emissions, including ammonia.

While the study looked at North Carolina farms, the findings can likely be replicated throughout the country as U.S. pig farmers adopt better genetics and target nutrition and greater veterinary care.

The environmental study shows hog farms’ contributions to nutrient levels and ammonia emissions have declined significantly over the last two decades. Other activity – increasing human population and growth in associated emission sources like automobiles, industry and human waste processing – has likely contributed to a general increase in ammonia emissions in the state.

The study also found that “advancements in swine production practices, changes in feed formulation, improved swine genetics, reduced nutrient excretion and other management changes have resulted in reduced nutrients in both primary and secondary lagoons.”

“U.S. pig farmers have a great story of sustainability to share, and this study validates it,” said Jan Archer, a pig farmer from Goldsboro, North Carolina. “Farmers have always been good stewards of the environment, and we are proud of the continuous improvement and innovative practices on our farms. As a pig farmer in the second-largest pork producing state in the country, I am proud of our record and believe these sustainability gains are being replicated by many of my fellow farmers in other states.”

A research summary of the environmental study is here and also online at pork.org.

Related Stories
New rule speeds leasing and permitting for federal oil and gas development
Meat stocks rose seasonally but remain below last year overall, while tighter butter inventories could support dairy prices, and belly stocks warrant close watch for pork markets.
A mid-January winter storm delivered snow, ice, and extreme cold to a broad swath of the U.S., disrupting transportation, stressing livestock systems, and adding cost and complexity to winter farm operations as producers look toward spring.
Heavier weights and strong late-year slaughter supported December production, but lower annual totals highlight ongoing supply tightness heading into 2026.
Strong production and rising stocks may pressure ethanol margins unless demand or exports continue to improve.
Placements and marketings beat expectations, but declining on-feed totals and feeder constraints keep the supply story supportive for cattle prices into 2026. Dr. Derrell Peel, with Oklahoma State University, joined us to break down cattle-on-feed numbers and provide his broader market outlook.

LATEST STORIES BY THIS AUTHOR:

FWSSR Communications Director Matt Brockman discusses the event’s competitions, safety preparations, and family-friendly activities during the opening weekend.
From Junior Heifer Shows to Mustang Magic competitions, the 23-day event brings together 4-H and FFA participants, livestock enthusiasts, and families to celebrate North Texas’ rich Western heritage.
CLAAS Senior Vice President for the Americas Region Eric Raby joined us to preview the new docuseries “CLAAS: Made for More,” premiering tonight at 9 PM ET only on RFD-TV.
Dairy farmer and Discover Ag co-host Tara Vander Dussen joined us to discuss the Whole Milk for Healthy Kids Act, her experience at the signing, and what’s next for her family and farm.
The Farm Bureau is making an urgent call to Congress for more farm support. Colton Lacina with Farmers National Company joined us to discuss farmland values and how market dynamics for the year ahead reflect stabilization rather than collapse.
Analysts say a Supreme Court decision on tariffs could reshape protein markets, strain U.S.-China trade, and force farmers to rethink global demand strategies.
Wayne Cockrell with the Texas and Southwestern Cattle Raisers Association joined us to discuss preparedness, producer awareness, and the industry’s response to New World screwworm concerns.
Agriculture Shows
Hosted by Scott “The Cow Guy” Shellady and RFD News Markets Specialist Tony St. James, Commodity Talk delivers expert insight into the day’s ag commodity markets just before the CME opens. Only on RFD-TV and Rural Radio SiriusXM Channel 147.
A look at the news, weather and commodities headlines that drove agriculture markets in the past week.
Everything profits from prairie. Soil, air, water — and all kinds of life! Learn how you can improve your land with prairie restoration, cover crops and prairie strips, while growing your bottom line.
Special 3-part series tells the story of the Claas family’s legacy, which changed agriculture forever.