Roughly 30 years ago I walked out of my last college chemistry course with my fingers crossed, hoping for a passing grade and a sigh of good riddance. The Periodic Table with chemical elements, symbols and atomic numbers was not on my list of favorite things.

A few weeks ago, I traveled to the East Coast to check out an odor control program that I had received several telephone calls about. Accompanying me to the 2,000-head finisher were a company swine business manager, a self-described inventor/entrepreneur … and a chemist.

Each took a turn explaining how the odor-control program evolved, how it worked. When the chemist took his turn, I could feel a panic attack reminiscent of those that fogged my brain during my college chemistry exams.

But, this particular, very patient chemistry professor soon realized that he was dealing with a chemistry-challenged student. I think his first clue came when I asked him to “dumb it down” for me.

He patiently explained the key chemical elements that contribute to odor, the role volatile fatty acids play, and the importance of dealing with the chemical challenges associated with odors above and below the slats, separately (see “Odor Busters,” p. 18). He went on to explain that the various acids in the pit and the number of carbons attached to each affects odor levels. “They all have one property in common,” he said. “They're volatile and your nose can pick it up. They stink.”

That I can understand. I wish he had been my college chemistry professor.

Did the odor abatement program deter all complaints initially lobbed at this unit, unequivocally? Not quite. One unsatisfied neighbor remains, but that pales in comparison to the 50 complaints filed per day before the program was installed.

Unable to make a “before” and “after” odor comparison myself, the best I can do is compare it to the many hog finishing units I've been in over the years. Some would bring tears to your eyes; others were not so bad.

Any objectionable smell from this unit was considerably lower than the “not-so-bad” finishers I've smelled.

I came away from the unit with a greater appreciation for chemistry and the likelihood that it holds at least one of the keys to unlocking the odor control challenge.

Searching for Answers

You will find other odor-control technologies in this issue and the Environmental Stewards of the Pork Industry insert (pages E1-16).

You may have noticed that we have sparingly reported on products and technologies with odor-control claims. I receive a constant flow of new product announcements and story leads claiming to have an answer to the challenge of controlling odors emitted from livestock production systems. Many are simply that — claims — without the science or third party field-testing and verification to support their claims. Some may work, but are cost-prohibitive.

I doubt that there's a single, silver bullet to solve these odor issues. But, there are some products and programs that work.

Because this issue has become an area of concern in our society, it is a high priority issue for our industry. Therefore, we feel an obligation to report new technologies that have proven to be effective in their individual settings. Some will likely find their way into best management practices of conscientious producers. The ultimate test, however, lies in the olfactory neurosensory cells in your neighbors' noses.

Scratch 'n Sniff

Speaking of noses, the planning commission of Ottawa County, Michigan recently took a unique approach to heading off odor complaints. They began distributing a brochure aimed at educating potential rural home buyers about the realities of living near agricultural operations. The brochure, supported by the Ottawa Farm Bureau and the Michigan State University Extension Service, reinforces the Michigan Right-to-Farm Act that protects farm practices that draw the most complaints:

  • operating farm machinery in the early morning and late at night, the noise and dust they create;

  • transporting farm products with slow-moving vehicles on local roads;

  • pesticide and fertilizer applications; and

  • the spreading, injecting of manure.



The attention-getter in the brochure is a light brown, boxed area labeled “manure odor.” The potential new country dweller is encouraged to scratch-n-sniff the area.

I can confirm that the odor in the box is a pretty good replication of what you might smell standing near a hog unit.

The easy-to-read brochure, entitled “If You Are Thinking About Moving to the Country You Might Want to Consider This….” is an excellent first step in helping rural newcomers understand the sights, sounds and smells of modern-day agriculture. As the saying goes: “forewarned is forearmed.”