Aaron Miller of Miller Livestock in Kinsman, Ohio. Bon Appétit buys half of all his hogs. (Photo by Sarah Piper.)

Last week, McDonald's announced it was making a move to end the use of gestation crates -- the especially despicable practice of confining pregnant sows in spaces roughly the width of their bodies. By May, their announcement read, they’ve requested concrete plans from their producers to phase out the practice.

In other words, the company managed to make a splash in the news without committing to a timeline. Of course, one of McDonald's biggest suppliers, Smithfield Foods, is supposedly four years into a 10-year process to phase out gestation crates by 2017 –- but it’s hard to know how much stock to put into their pledge considering the complaint filed by the Humane Society of the United States (HSUS) with the Securities and Exchange Commission in November alleging that Smithfield has been making false and misleading claims about their practices.

Aerial shot of the Nelson Faria Dairy in Royal, Wash. Note the tiny dots that are the dairy cows congregating in the holding pens. (Image by Google Maps.)

In a precedent-setting decision earlier this month that received scant national coverage, a federal district court judge in Washington state ordered a CAFO (Concentrated Animal Feeding Operation), also known as a factory farm, to monitor groundwater, drainage, and soil for illegal pollution resulting from its grossly inadequate manure management practices in violation of the Clean Water Act. This first-ever ruling holding a CAFO accountable for its pollution was a result of a lawsuit by the nonprofit Community Association for Restoration of the Environment (CARE) against the Nelson Faria Dairy in Royal, Wash. The ruling upholds the terms of a 2006 settlement CARE had with the dairy’s previous owners, which the current owners subsequently ignored.

The case underscores one of the major problems with CAFOs, which is the massive amount of manure they produce and the manners by which operators dispose of it, which have major environmental implications. According to the EPA, “a single dairy cow produces approximately 120 pounds of wet manure per day,” which is “equivalent to that of 20-40 people.” The quantity of manure produced by one dairy cow can be multiplied on a CAFO by hundreds or, in some cases, thousands of heads. This higher concentration of CAFO animals leads to a higher concentration of animal waste, a problem that holds true for all types of livestock raised in these operations. As CARE describes the scale of the waste problem:

Okay to be fair this is a German one. My image research indicates that U.S. crates usually don't have tops but Creative Commons pictures of them are hard to come by.

McDonald's has announced that it's requiring pork suppliers to phase out gestation stalls -- pig-sized pig cages where pregnant sows are confined, often unable to stand up or move around. Whoa, McDonald's food has actual pigs in it? Who knew.

A screen shot from an ABC news report about the probem (click to watch the video).

It is said that nature abhors a vacuum. Well, according to this report from the Minnesota Daily, nature also abhors factory farms. Large midwestern hog farms have for the last few years been battling a mysterious foam that is forming on top of their barns. In the worst case scenarios, the foam blocks ventilation ducts and the barns explode -- yes, explode -- killing the thousands of hogs inside. The report reads:

The foam traps gases like methane and when a spark ignites it causes an explosion. About a half dozen barns in the Midwest have exploded since the foam was discovered in 2009.

In mid-September 2011, a barn in Iowa was added to the growing number of barns taken down by the foam. In the explosion, 1,500 pigs were lost, and one worker was injured.

Methicillin-resistant Staphylococcus aureus (MRSA). (Photo by the National Institute of Allergy and Infectious Diseases.)

A few weeks back, we reported on a study out of the University of Iowa that tested supermarket pork for antibiotic-resistant Staph bacteria (aka MRSA). The researchers found MRSA at the same rate for conventionally raised meat and for meat raised without antibiotics. In her well-respected WIRED blog on the topic, Superbug, Maryn Mckenna summed up the media response to the news like this:

There’s just as much resistant bacteria on drug-free meat as there is on conventional meat, so why spend the money — or raise the alarm over farm antibiotic use?

But she disputed that conclusion:

My takeaway is that, in its underlying data, the study proves what campaigners against ag antibiotic use keep saying: that once you use antibiotics indiscriminately and drive the emergence of resistant organisms, you have no way of predicting where that resistance DNA will end up.

For most of us, any sign of MRSA in our food is pretty creepy. (Although the bacteria doesn’t make it through the cooking process, meat can still be what scientists call a “vector,” or a mode of transmission, when we handle it). So we tracked down McKenna, who is also a columnist and contributing editor for Scientific American and the author of Superbug: The Fatal Menace of MRSA. Her take on the research may surprise you.

If a bite of food falls on the ground, often we pick it up and eat it. Five second rule, right? But if it falls in something gross or we haven't cleaned the floor in awhile, we don't eat it. Because that's gross. Especially if your floor is covered in chicken shit.

It's unclear, then, why we are okay with eating chickens that have been transported in crates that are never, ever cleaned. Never. By 80 percent of poultry growers, at least. Which means that there's a 4 in 5 chance that your chicken dinner was rolling around in something far nastier than a little floor dust.

Photo by Edmund Yeo.

On Wednesday, thanks to a collaboration with a new nonprofit news organization called the Food and Environment Reporting Network, MSNBC ran an in-depth report on ractopamine hydrochloride, a drug commonly used in pigs and known on the market as Paylean.

The story is important for two reasons. First, it has the potential to widen the public's understanding of a powerful, overused drug, and to help us dig down into what it really means when we hear about the use of growth-promoting drugs in meat. Second, it’s the mark of a new voice in food journalism -- one that’s well worth paying attention to if you’re interested the intersection of food and the environment.

Farmworkers shoulder tools at the end of the day. (Photo by Charles O'Rear.)

I wasn’t surprised when the Associated Press reported last week that Colorado-based Jensen Farms had been fined for housing its workers in unsanitary, unsafe conditions (workers had little choice but to crowd into company-owned "motel" rooms that lacked beds, laundry facilities, and smoke detectors). After all, the huge cantaloupe farm had been found responsible for last fall’s deadly listeria outbreak -- a major food safety oversight that killed at least 30 people, made 146 people sick, and soured melon season for farmers around the nation by planting a fear of cantaloupes in the minds of many eaters.

And although the AP story reads, “The fine was not linked to the outbreak,” it’s clear that there are links between food safety and the treatment of workers.

This post is part of Protein Angst, a series on the environmental and nutritional complexities of high-protein foods. Our goal is to publish a range of perspectives on these very heated topics. Add your feedback and story suggestions here.

A field of soybeans -- most of which are grown for animal feed. (Photo by Carol Vanhook.)

Now that we’ve touched on how much protein we need, let’s talk about how the production process behind high protein foods impacts the environment.

First, the big picture: While meat consumption has gone down slightly here in the U.S. in recent years, the rest of the world appears to be on the opposite track. Nearly half the protein eaten in the developed world comes from animals (compared to 28 percent of protein, worldwide) and, as incomes in larger developing nations like Brazil, India and China have picked up, so has the taste for meat.

World meat consumption more than doubled between 1950 and 2009 (bringing annual intake per person to over 90 pounds or around a quarter pound a day), and the uptick in consumption of eggs and milk has been similarly staggering. If we continue at this rate, by 2050 we’ll be eating two-thirds more animal protein globally than we are today.

Add to all this the fact that animal protein is more resource intensive to produce than fruits, vegetables, and grains, and you begin to understand why it’s especially important that the world gets its protein plan in order.

We really do try to Pollan it up and do the whole “eat food, not too much, mostly plants" bit. But “mostly plants” obviously means “sometimes bacon.” And maybe the farmers' market wasn't open, so we bought that bacon at the store. Oh, but it was good bacon! "Raised without antibiotics" bacon! That's something, right?

Nope, not really, according to a new study from a group of University of Iowa scientists. This group tested 395 samples of pork from 36 stores in Iowa, Minnesota, and New Jersey. Of those, 6.6 percent had creepy, drug-resistant staph bacteria (shorthand: MRSA) on them. And there was no difference, statistically, between the normal pork products and the ones raised with alternative, antibiotic-free methods.