In agriculture we find ourselves in the news more frequently than we'd like in a negative light. However, if there is one issue that seems to be prevalent with misinformation shrouded in fear, it would be the discussion surrounding antibiotic use in livestock.

Antibiotic use and the issues surrounding it are certainly complex discussions that can lead to confusion and a lack of credible information. Three of the major conversations center on how antibiotics are used in livestock, whether any of those antibiotics are in the meat we eat, and how use in livestock may contribute to a potential resistant bacteria problem down the road.

Kacy Atkinson Logan County Extension Agent
Kacy Atkinson Logan County Extension Agent

So let's start with the first topic of how antibiotics are used in the livestock industry. Antibiotics have really only been used in veterinary medicine for a little over 40 years, despite penicillin having been developed in the 1940s. While antibiotics used in human medicine only need FDA approval, antibiotics in veterinary medicine must pass a rigorous process that includes not only the FDA, but the USDA and EPA as well. Additionally, animal antibiotics must be reevaluated on a yearly basis in order to keep being used.

Once an antibiotic is approved, it is used for three main purposes: disease prevention, disease control and disease treatment. At any livestock operation, these are three essential components of running a healthy and humane operation that takes care of the well-being of its animals.


When an animal becomes sick, it will be treated with an appropriate antibiotic in a dosage directly related to the size of the animal, for a prescribed amount of time, just like in human medicine. Once that animal gets well, hopefully it will never be sick again in its lifetime.

Similar to taking your child to daycare, where they are exposed to an abundance of new germs and potential illnesses, which they then bring home and often share with you, livestock can undergo similar situations. The average cow herd in the U.S. is only 50 head. So, we have backgrounders and stockers that put together those small herds of 50 into herds of a few thousand in preparation for the feedlot.

When those cattle meet, just like your child was exposed to new kids, cattle are exposed to new cattle that may have different germs and immunities. Antibiotics are given at a very low dose simply to help the cattle transition through that phase without becoming ill. When we get sick we often get well without any medications. When cattle get sick, if they aren't treated, they can die as they typically only get severely ill. Keeping them healthy from the beginning is a benefit to their overall wellbeing.

Antibiotics are very expensive, often running $30-50 per dose, so it is essential to use them wisely for both the benefit of the animal, and the ability of the operation to stay in business. When we do give antibiotics, we keep careful records of what we gave the animal, when we gave it to them, and how much antibiotic the animal received.

When it comes to the discussion of antibiotics being used for growth promotion, typically a special compound called an ionophore, an antimicrobial, is used. While all antibiotics are antimicrobials, not all antimicrobials are antibiotics. So, while it is classified similarly to an antibiotic, an ionophore isn't a disease prevention, treatment or control substance, and therefore is not classified as a therapeutic drug. Also important to note is that ionophores are never used in human medicine, as they would kill us because we aren't ruminant animals with four stomachs.

Just like when the doctor has you eat yogurt when you are on antibiotics to keep the good bacteria in your stomach alive and functioning, ionophores specifically work with the bacteria in the rumen to make the good bacteria function better and suppress the bad bacteria. This allows the animals to make better use of the nutrients they are given to grow and support body functions more effectively. Because it allows the good bacteria to work, it is effective at helping control bloat, which can ultimately kill a ruminant animal if untreated.

Judicious use of antibiotics is at the heart of every operation, because we are responsible for the wellbeing of the animals in our care. Our stewardship of one of the only tools we have available to keep our animals healthy is essential for the future of our industry, and it's a responsibility we never take lightly, for the sake of animals and humans alike.