Antibiotic use on swine farms increases efficiency, profits

Antibiotics used on swine farms may stir controversy about their potential role in the rise of anti-bacterial resistance, but a new study says their use means significant production efficiency and a 9 percent boost in pork producer profits.

The study, published in the December issue of the Journal of Agricultural and Applied Economics, provides an economically detailed look at the use of antibiotics for growth promotion following dramatic changes that have altered the face of the U.S. swine industry in the last three decades. It is based on industry statistics compiled in the 1990s.

Researchers at the University of Illinois at Urbana-Champaign found that for average modern-day swine facilities antibiotics boost daily growth and reduce swine death rates during the growth-finisher stage of production. Swine farmers operating a 1,020-head finishing barn, researchers found, realize a profit of 59 cents per pig in annual returns.

“Antibiotics used for growth promotion have a positive impact on production efficiency and producer profitability,” said principal investigator Gay Y. Miller, a professor of veterinary pathobiology and of agricultural and consumer economics.

“When production is more efficient, there are more products for consumers at lower prices. Improved efficiency also means that fewer numbers of animals are needed to provide the same amount of product. Using less resources takes fewer farms to produce the same amount of pork, less manure is generated and you see a reduction of other environmental concerns.”

Antibiotics have been used widely at subtherapeutic levels for livestock production since the 1950s, but such use has been questioned in recent years because of the rise of antibiotic resistance in human and veterinary medicine.

A previous study by Iowa State University had found the benefit of antibiotic use in the swine industry to be almost five times higher than the findings of the new research. However, that study, Miller said, used European statistics.

The new study looks solely at the U.S. industry, which has become concentrated, with large production facilities and advances in genetics and production approaches. A preliminary analysis of even newer data, she said, suggests that productivity and profit estimates may be somewhat higher, though still not as high as those found in the Iowa State research.

The newly published study suggests that a ban on antibiotic use, as has occurred in Denmark, would result in sharp increases in production costs at U.S. facilities, said co-author Paul E. McNamara, a professor of agricultural and consumer economics at Illinois.

“Many analysts speak about sub-therapeutic use of antibiotics as if it had no production value at all,” McNamara said. “This view is puzzling to both producers and economists, since antibiotics used in animal agriculture constitute a significant input into the industry. With the competitive pressures producers face, if the input did not provide a significant production benefit, we would expect producers to drop its use in order to save money and realize higher profits.

“Our results help to quantify the magnitude of this input’s importance in today’s production environment,” he said. “Understanding its importance and role in production is necessary if we are going to shape antibiotic-use policies that consider both the public health risks of an application as well as the economic benefits of its use.”

The study also found that antibiotic use might be curtailed at facilities that adjust their feed rations at five or more times to adjust for nutritional needs in various growth and finishing stages. Such an approach reduced the financial gain of antibiotics, but it did not work at facilities adjusting food ratios four or fewer times. Additional work is needed to understand how antibiotics provide specific benefits in the various production phases.

In addition to Miller and McNamara, Kenneth A. Algozin, a former postdoctoral researcher at Illinois, and Eric J. Bush, a veterinary epidemiologist with the U.S. Department of Agriculture, contributed to the study.

The study was funded in part by the Illinois Council on Food and Agricultural Research