In its recommendations for new federal dietary guidelines on healthful eating, a panel of health and nutrition professionals delved into “sustainability,” telling Americans that a diet higher in plant-based foods is better for the environment than animal-based foods, according to Ron Prestage, DVM, writing in The Hill.

He goes on to write that it it true farmers who grow crops today use less water and pesticides but livestock and poultry farmers have done their part to become more environmentally friendly, too.

In the US pork industry, for example, over the past 50 years hog farmers like Dr Prestage have cut their carbon footprint by 35 per cent, reducing water usage by 41 per cent and the amount of land needed by 78 per cent, according to a study published in the Journal of Animal Science/Journal of Dairy Science.

Those reductions have come mostly through production efficiencies, including improvements in swine genetics, housing — moving pigs indoors — manure management and feed rations. Take pigs’ feed efficiency: that has improved 33 per cent over the past 50 years, according to the study cited above. That means they are consuming less feed for every pound of meat produced, less land is being used to grow grain, and the amount of manure produced has declined.

To be better environmental stewards, food-animal farmers in 1998 entered an environmental dialogue with the US Environmental Protection Agency and the US Department of Agriculture. One result of those talks was EPA’s Clean Water Act rule for concentrated animal feeding operations (CAFOs), which overhauled how the water law applies to livestock farms. The rule set a 'zero-discharge' standard for CAFOs that prohibits farms from allowing manure to get into the nation’s water supplies, with violations carrying a penalty of up to $37,500 a day.

America’s livestock and poultry farmers also worked with EPA to develop a groundbreaking study of air emissions from farms. Conducted from 2007 to 2009 by Purdue University scientists, it collected data on emissions of ammonia, hydrogen sulphide and methane to better understand the impact on the environment of raising food animals.

All those efforts have paid off, according to Dr Prestage. Looking at data from eight of the top pork-producing states, for example, since 2000 fewer than one per cent of hog farms have had manure 'spills' and the majority of those had no impact on water quality. Over the past decade, most hog farmers have upgraded their manure storage facilities to ensure that manure stays where it’s stored until applied correctly to crop land. On efforts to clean the air, EPA is evaluating the data gathered under the emissions study and is using it to develop standards for farms.

Dr Prestage concluded: "We’ve done all of that while significantly increasing meat production. This year, for example, 68,000 hog farms are expected to produce more than 22 billion pounds of pork compared with 1965, when more than one million farms produce just 12 billion pounds.

"So on Earth Day, let’s remember these facts: Modern livestock and poultry production is environmentally sustainable – the dietary guidelines panel got that wrong – and the farmers who produce pork, beef and chicken are among the best stewards of our natural resources."

Dr Prestage is a hog and turkey farmer and veterinarian from Camden, South Carolina and president of the National Pork Producers Council.