I recently attended an Indiana Rural Caucus meeting, where I heard from Paul Ebner, Ph.D., an assistant professor of the Department of Animal Sciences at Purdue University. He discussed the research he and his team have done on how antibiotics are used and the effects of antibiotics in livestock production. I wanted to take this opportunity to further explain the use of antibiotics in livestock. There are two main reasons livestock producers administer antibiotics: first for the prevention of common diseases, and second for the treatment of specific diseases.
Preventative antibiotics are given in lower doses to prevent common diseases, especially after stressful experiences such as weaning or transport. Antibiotics given for treatment are usually given in higher doses to treat a specific infection. It was found that animals given preventative doses tend to grow more efficiently. Very few antibiotics, however, are used exclusively for growth promotion.
Concerns have been raised about the use of antibiotics in livestock and how that might affect humans. While researchers have some ideas, it is unclear as to the amount of antimicrobials that are used in veterinary medicine versus human medicine because it is not well monitored. This has been a major obstacle in Dr. Ebner's studies.
Livestock producers have special interest in how animals develop resistance to some antibiotics. There are some bacteria that are naturally resistant. Giving an antibiotic can result in an increase of the reproduction of the resistant bacteria by eliminating their competition. Bacteria can also exchange genes, so other bacteria can become resistant by acquiring the necessary genes, which is very similar to the human process.
Currently, the impact on human health by the use of antibiotics in livestock production is very unclear. There have been very few clear cases where antibiotic resistance that developed on the farm affected antibiotic resistance in bacteria in human populations.
Dr. Ebner has found that in other countries, such as Denmark, where they have phased out the use of preventative antibiotics, it has increased their use of antibiotics to treat specific diseases. While disease occurrence has increased, the overall use of antibiotics has decreased.
This is a valuable research project to the livestock producers of Indiana and the Indiana Rural Caucus. We are working to advance and help Hoosier rural communities and greatly appreciate the commitment and research of Dr. Ebner and his team.