Frequently Asked Questions

Q. What is the subtherapeutic use of antibiotics?

A. Subtherapeutic usage entails the use of antibiotics for anything except for sickness. Doses are generally less than 50 milligrams per ton of animal weight. At this dosage, antibiotics can act as growth promoters that increase the animal’s output and value. This type of use has increased the daily weight gain of animals, has improved the feed-to-weight gain ratio, increased the voluntary feed intake of the animal, and decreased illness and morbidity.

Q. Why should we care about the subtherapeutic use of antibiotics in agriculture?

A. The subtherapeutic use of antibiotics in agriculture is unnecessary. Although advocates of this practice contend it is necessary to satisfy the ever-growing demand for eggs, meat, and milk, the subtherapeutic use of antibiotics in agriculture mainly serves to compensate for improper animal husbandry techniques, like the use of confined and unsanitary living conditions, and the feeding of an unnatural diet to the animal populations. Animal meat is a source for food-borne illnesses, including Salmonella and Escherichia coli O157:H7. The subtherapeutic use of antibiotics is producing more resistant strains of these illnesses, prompting grave human health concerns.

Q. There seem to be a lot of benefits to the subtherapeutic use of antibiotics, how can it be so bad?

A. While there seems to be benefits of using antibiotics in this manner, there are also many consequences. One important consequence is the production of antibiotic-resistant strains of common food-borne illnesses. A second consequence is the diminishing ability of humans to treat common diseases that were once easily treated by our current drug arsenal. As antibiotic usage becomes more common, more diseases become resistant to the antibiotics being used to treat them. Thus, when humans become sick, it is more difficult to treat the patient effectively. The use of antibiotics in a subtherapeutic manner only hastens this process. Third, studies have shown that, as animal herd size grows, the use of antibiotics becomes preventive rather than therapeutic. Therefore, as concentrated animal feeding operations (CAFOs) become a more common method of animal husbandry, antibiotic usage will increase. If animals were raised in healthier conditions, the use of antibiotics as a preventative would not be as necessary. Lastly, antibiotic usage also has been linked to the management style of the individual agricultural operator. It is simply an individual’s choice to use antibiotics extensively, not necessarily a requirement.

Q. What is the therapeutic use of antibiotics and which antibiotics used in human medicine are commonly used in agriculture?

A. Therapeutic use is the use of antibiotics to treat bacterial infections and to help an animal recover from an infection. This type of use is appropriate and should be continued. The following antibiotics are routinely used in human medicine and agriculture: fluoroquinolones, penicillin, tetracycline, erythromycin, lincomycin, tylosin, and virginiamycin.

Q. Are there any other antibiotics that are used in the agricultural industry?

A. Drugs known as ionophores, which alter the stomach microorganisms to promote the bacterial conversion of feed, are sometimes considered antibiotics. They are considered antibiotics because they do provide some protection against parasites. These are not generally a human health concern.

Q. How are antibiotics administered to the animals?

A. For cows and pigs, antibiotics are commonly administered through their feed; for poultry species, through their drinking water.

Q. Are there any alternatives to using antibiotics in a subtherapeutic manner that will have the same effects on animals?

A. The most basic alternative is adjusting the living conditions of livestock to ones that are more natural and allow the animals to express their natural behaviors. Living conditions should include: access to outdoors, sunshine, fresh air, and shelter; ample space and freedom of movement; pasture for ruminant animals; and, appropriate clean, dry bedding material. Chickens should be able to spread their wings and take “dustbaths,” cows should have grass to graze in, and pigs should be able to display their natural curiosity and rooting behavior. Disease and mortality would be significantly reduced if the crowded, stressful, and unsanitary conditions of concentrated animal feeding operations were eliminated.

There have been a variety of studies that have looked into alternatives to antibiotics. A few of the studies were presented in an article that appeared in FASS on January 14, 2002. Some of the research revealed that cytokines, probiotics, enzymes, and herbs – such as garlic, echinacea, goldenseal, and peppermint – yielded promising results. Although more research is needed, alternatives to antibiotics are available and are safe to use and, more importantly, can replace the practice of using subtherapeutic doses of antibiotics in healthy livestock.

Q. Is my health at risk if I eat meat from animals raised on antibiotics?

A. There is increasingly strong evidence that humans are at risk from eating meat that comes from livestock reared on subtherapeutic antibiotics. There are strong trends indicating antibiotic-resistant food-borne bacteria are on the rise and are primarily transmitted from the food individuals consume. Antibiotic residue on meat can be dangerous by either promoting an allergic reaction or increasing the amount of antibiotic- resistant organisms in one’s digestive tract.

Q. The problem of antibiotic resistance seems to be more a result of improper use by humans, not the agricultural industry. Why should agriculture be penalized until there is more direct evidence linking it to the problem of resistance?

A. The substantial problem of resistance has been attributed to antibiotics being improperly used, to individuals who fail to complete a fully prescribed round of antibiotics, and to the introduction of bacteria-killing products. However, one improper use by humans has been to use antibiotics in healthy animals. Rather than waiting to see what happens, and with alternatives available, the only responsible action would be to discontinue the subtherapeutic use of antibiotics.

Q. Have there been any cases where animals have been raised without the use of subtherapeutic antibiotics?

A. Scandinavian countries, specifically Sweden and Denmark, have had bans in place, since 1986 and 1998 respectively, eliminating the use of antibiotic growth promoters. In Sweden, the use of antibiotics has decreased by over 75% since the ban took effect and, in Denmark, the amount of antibiotics used decreased by over 30,000 kilograms in one year. There has been no increase in the therapeutic use of antibiotics since a small increase occurred in Sweden immediately following the plan.