WASTE MANAGEMENT
PIH-33
PURDUE UNIVERSITY • COOPERATIVE EXTENSION SERVICE • WEST LAFAYETTE, INDIANA
Controlling Odors from Swine Buildings
Authors
J. Ronald Miner, Oregon State University
Clyde L. Barth, Clemson University
Reviewers
Russ and Mary Jeckel, Delavan, Illinois
Dale Purkhiser, Michigan State University
exact nature of this odor is a function of the ration fed to the animals, the animal’s metabolism, and the environmental conditions under which decomposition occurs. Therefore, individual facilities can have differing odors; anaerobic lagoons have odors easily distinguishable from deep pit or scraped buildings.

Manure decomposition is not the only odor source. Rotting feed materials may also contribute an objectionable odor. Some food processing by-products fed to livestock are particularly notorious. Ensiled cannery wastes, wet whey, cooked garbage, and other decomposable materials deserve particular attention. Recognize, however, that feeding of these by-products to livestock is frequently the best use for them — thereby converting them to nutritious feeds. The cost of solving the odor problem must be balanced against the benefit of using what might otherwise be a wasted resource with its inherent environmental cost.

Other odor sources include dead animals not quickly buried or removed from the site, pesticide sprays, and manure handling facilities. Each of these odor sources can be handled by appropriate control procedures.

Odor Measurement and Analysis
Considerable effort has gone into identifying compounds resulting from manure decomposition. These gasses, when released into the air, are the odorous constituents. Ammonia, hydrogen sulfide, skatole, indole, and the amines and mercaptans are the most common. Although there is merit in identifying these compounds as released, this help is limited in the design of an odor control program.

More usable odor measurements include odor intensity — more often measured in the field with a Scentometer. This device consists of a plexiglass box held in front of the nostrils so that only air which has passed through an activated carbon filter is inhaled. By standing on the site
Odor control is a significant problem for pork producers throughout the country. The problem most often consists of neighbor complaints and occasional legal actions seeking either monetary damages or court injunctions. To operate compatibly within the community and to provide maximum self-protection, the pork producer must be aware of some basic information and strategy concerning odor control and practice those techniques appropriate to the location.

Odors are primarily a subjective response; there are few universally good or bad odors. People react to odors according to their attitudes and previous experience. This factor is usable by pork producers as they maintain an image of responsibility and productivity. Operators of well-maintained and attractive facilities who have maintained a cooperative public attitude are seldom subjected to odor complaints. Odor frequently becomes an issue along with complaints of water pollution, flies, noise, and other issues when there is faulty site selection, improper facility design, or inadequate management.

Compounds emanating from swine buildings have never exceeded safe air standards and are not hazardous to humans. Under certain situations, such as manure pit agitation, however, dangerous gas concentrations can develop. Odors, therefore, are nuisance pollutants and, like other nonhazardous assaults on the environment, must be regarded accordingly. Important are intensity, duration, and frequency of detection. Within an agricultural community, it seems appropriate that livestock odors be occasionally noticed, but nuisance complaints result when intensity or frequency exceeds reasonable limits.

Sources of Odors
Odors from swine production facilities arise predominantly from manure decomposition. Odor from fresh manure is generally less offensive than odor released when manure undergoes anaerobic or septic decomposition. The