Antibiotic Resistance…Part 3

Antibiotic resistance is a big topic, hence the reason I decided to break this blog post into four pieces. In case you have missed them, check out Part 1 which provides a little overview of feeding antibiotics to cattle, Part 2 talks about what else is regularly fed to cattle. Today, in Part 3 I will go over who monitors the livestock antibiotic world, and why that is important to you and I.

Feedlot cattle

Who monitors antibiotic and drug use in livestock?

All antibiotics used to treat animals have been approved by the U.S. Food and Drug Administration (FDA). The FDA is responsible for protecting public health by assuring the safety, efficacy and security of human and veterinary drugs, biological products, medical devices, our nation’s food supply, cosmetics, and products that emit radiation. FDA is also responsible for advancing the public health by helping to speed innovations that make medicines more effective, safer, and more affordable and by helping the public get the accurate, science-based information they need to use medicines and foods to maintain and improve their health.

Did you know that the Food Safety and Inspection Service National Residue Program (FSIS NRP) (yes, there is an entire division dedicated to monitoring drug resistance!!) tests all domestic and international meat, milk, and egg products for antibiotic residue? The U.S. government says that NO (meaning zero tolerance) beef (as well as other species including pork, poultry, etc.) with antibiotic residues exceeding the FDA standards will be allowed in the food supply!

Dr. Dee Griffin, DVM (Doctor of Veterinary Medicine) says that in addition to these samples, a USDA veterinarian will take samples of “suspicious” animals at the packing plant. “Suspicious” animals may include animals with a disease lesion, or animals that look like they have been treated for illness recently. If the tissue from these animals tests positive for drug residue the carcass will be condemned and NOT allowed in the food supply! Interestingly, in 2012, approximately 200,000 tissue samples were taken from beef alone! Of those less than 1,000 tested positive for a residue, that is one half of one percent testing positive for a residue. And while we hope to get that number to zero someday, we are thrilled that testing is occurring, and those that do test positive are being condemned and not allowed in the food chain!

The Center for Veterinary Medicine (CVM) regulates the manufacture and distribution of food additives and drugs that will be given to animals. These include animals from which human foods are derived, as well as food additives and drugs for pet (or companion) animals. The CVM is also responsible for regulating drugs, devices, and food additives given to, or used on, over one hundred million companion animals, plus millions of poultry, cattle, swine, and minor animal species.

Have you ever heard of the Generic Animal Drug and Patent Restoration Act? This Act requires that each sponsor of an approved animal drug must submit to the FDA certain information regarding patents held for the animal drug or its method of use. The Act also requires that this information, as well as a list of all animal drug products approved for safety and effectiveness, be made available to the public. This list must be updated monthly under the provisions of the Act. The list, known as the “Green Book,” was first published in January 1989. Updates have been added monthly since then. Each January, the list is published in its entirety.

Finally, did you know that Veterinarians have to take an oath? Yes, according to the American Veterinary Medical Association (AVMA) the oath states:

Being admitted to the profession of veterinary medicine, I solemnly swear to use my scientific knowledge and skills for the benefit of society through the protection of animal health and welfare, the prevention and relief of animal suffering, the conservation of animal resources, the promotion of public health, and the advancement of medical knowledge. I will practice my profession conscientiously, with dignity, and in keeping with the principles of veterinary medical ethics. I accept as a lifelong obligation the continual improvement of my professional knowledge and competence.”

I think it is clear and maybe we can all begin to agree there are many regulatory bodies in place to protect us and our food supply.

Sneaking in for a little snack.

Stay tuned for the fourth and final (for now) installment of the antibiotic resistance discussion tomorrow.


Antibiotic Resistance…Part 2

Yesterday I started the Antibiotic Resistance series to shed some light on why antibiotics are fed to cattle. If you have not already, please take a minute to read Part 1, as it provides some great background information.

In addition to Tylan, rumensin can be fed which is used to keep the animal’s stomach healthy and to prevent coccidiosis. Coccidiosis is caused by an intracellular protozoan parasite that grows in the cells of the intestines. The protozoa are passed through the feces of cattle and are picked up through things cattle come into oral contact with: feed, water, hair coats, udders, other surfaces, etc. By time cattle reach six months of age, it is estimated that 100% are infected, but only 5% show signs of infection. Symptoms include bloody diarrhea, poor growth, severe weight loss, straining to have a bowel movement (due to inflammation), and in some cases, death. This most commonly affects young cattle, but it may also occur in adult cattle. Anticoccidial drugs are most effective very early in the onset of the disease, before symptoms are visible. Therefore, it is generally advisable to feed young or just weaned calves (who are experiencing high levels of stress) an anticoccidiostat in their feed to control this protozoa. Rumensin and other anticoccidiostats are ionophores not antibiotics, which are NOT used at all in human medicine.

Cattle enjoying their meal.

Anne Burkholder has invested a lot of time investigating antibiotic resistance and the link between animals and humans. On Anne’s blog you can find a category dedicated to Antibiotics, Hormones, and other growth promotants – I encourage you to check it out.

Anne Burkholder
Anne Burkholder

Earlier I mentioned a withdrawal date. A withdrawal date is the amount of time that must pass after an animal has received an antibiotic to the time when that animal or the products it produces can be consumed. This is measured in days, and is taken very seriously by persons involved in food production. The livestock industry has two programs in place for livestock farmers designed to enhance and reinforce proper animal care practices, recordkeeping, and the responsible and judicious use of antibiotics. These programs are Beef Quality Assurance (BQA) and Pork Quality Assurance (PQA).

Withdrawal dates clearly defined on a medication label.

In December 2013, you may have heard about the FDA’s (Food and Drug Administration) announcement to remove “improve growth, gain, and efficiency” use of feed grade antibiotics. While this article was written for beef farmers, I think Dr. Dee Griffin does a nice job of explaining what it all means here.

Dr. Dee Griffin

Many people point the finger of blame at the agricultural industry, but there are many other factors that should be considered. First, the overuse and abuse of antibiotics by humans should be discussed. Antibiotics can be obtained over the internet and in some countries without a prescription, leaving people to self-dose and self-medicate. Additionally, persons may take antibiotics for viral infections, like the common cold, when they are not effective. People may also contribute to this problem by not completing a course of antibiotics; they may stop when they feel better or save part of the dosage to decrease expenses associated with a doctor visit and prescription. By not completing a prescribed dose of antibiotics, you are not effectively killing the bacteria that are causing the infection; the bacteria that were not killed have become stronger and in turn resistant to that antibiotic at that level and duration of dosage. Finally, we live in an antibacterial society. How many of you have hand sanitizer, antibacterial soaps and lotions, antibacterial wipes, etc. at home/work? Each time you use these they may kill some bacteria, but the bacteria that are not killed become stronger and more resistant! So take a moment to ponder how you may be contributing to the antibiotic resistance level on a personal level.

Hereford cattle in a feedlot pen.

Stay tuned for Part 3 of the Antibiotic Resistance discussion…

Antibiotic Resistance…Part 1

Recently, I did a series on meat labeling terms. Grain-fed and grass-fed, organic and natural programs, and no hormones and no-added antibiotics.

Blog reader, AW, left this message: The grass vs. grain article and follow up, while touching on things most people don’t know, seems to avoid the most common issue in consumers’ minds: Thinking that grain-fed cattle must be given antibiotics because they are not “built” to consume corn, and that this contributes to antibiotics resistance.

Now before you read this I should tell you that even though I am definitely pro-Ag, but I am very against the misuse and irresponsible use of antibiotics! I very strongly believe that if/when antibiotics are needed and used, that they are administered judiciously with great responsibility. In many cases, when an animal becomes ill enough to need an antibiotic, it is life and death. If the animal does not receive the antibiotic it may suffer and die! So it is the responsibility of the livestock farmer to ensure an animal receives a quick diagnosis and the proper treatment! Just like you, I do not want to eat meat, or consume other livestock products where the withdrawal period was not followed! I think AW makes a good point. Many people are concerned about antibiotic resistance, and becoming resistant to antibiotics through the meat they eat. So let’s take a look at the facts and gain a better understanding of antibiotic resistance together.

Beef farmers practice responsible use of antibiotics.

What is antibiotic resistance? Antibiotic resistance occurs when an antibiotic loses its ability to effectively control or kill bacterial growth. Why is this concerning? The bacteria become “resistant” to an antibiotic and will multiply. The next time illness occurs (in human or animal); it may take a different antibiotic or a stronger dose of an antibiotic to see a difference.

South Dakota State University Extension put together a nice antibiotic fact sheet. Antibiotics are given to people and animals to treat or prevent illnesses caused by bacteria. Antibiotics are given to livestock to relieve the pain and/or distress from the illness, to make them feel better, and recover. Just like with people, antibiotics have no effect on diseases caused by viruses or parasites. Antibiotics can be administered several ways, including an injection under the skin, via a pill (aka bolus), or mixed in the feed or water. When an animal is very sick an injectable antibiotic is the quickest route to get the animal on the road to recovery. It should also be mentioned that if animals are sick, like us, they don’t feel like eating or drinking, so mixing an antibiotic into the feed or water is not always effective. All livestock antibiotics approved by the FDA (Food and Drug Administration) since 1988 require a prescription from a veterinarian who has developed a relationship with the livestock producer and can help determine the best options for disease prevention and treatment. Feedlot co-owner and operator, Anne Burkholder of Will Feed, Inc., Cozad, NE, exemplifies what a responsible antibiotic user looks like in this blog post on Feedyard Foodie.

A common myth is that antibiotics are mixed into ALL livestock rations. That is untrue. There are certain times in an animal’s life where things are more stressful than others, and antibiotics in the feed can make good sense. For example, if animals are co-mingled at a young age they are more likely to transmit bacteria back and forth (just like your kid’s daycare or school classroom). It is hard on their little bodies, and being sick can take a toll on them and make recovery harder. Also, when animals are weaned from their mothers there can be a lot of stress. High levels of stress often result in weakened and susceptible immunity which opens the door for bacterial infections. Weather conditions may also take a toll on livestock. Extreme fluctuations in temperature and the inability to get dry or warm can result in illness or pneumonia. Finally, as an animal approaches its final weight, antibiotics may be fed to help prevent liver abscesses, which may be caused from a high ration of grain in the diet. (I believe this is what AW was referring to, and I will elaborate more).

The use of antibiotics in feed or water is totally at the discretion of the livestock farmers. Some beef farmers do not feed antibiotics during these times of stress, and will just treat animals that may get sick, and some may treat all the animals to keep them all healthy. Also, animals that are fed for a niche market (i.e. organic, naturally raised, or no antibiotics used systems) will not have received an antibiotic (in these programs if they receive an antibiotic, then they are completely removed from the program). Geographically, there are some locations in the U.S. (Midwest – Iowa and Eastern Nebraska, South Texas, and Desert Southwest – Arizona and California) that feed fewer antibiotics in the feed because of a diet higher in roughages and fewer fluctuations in weather. There is no right or wrong method, each beef farmer weighs the advantages and disadvantages of the cost (antibiotics are expensive to manufacture and purchase), labor, time, efficiency, withdrawal period, and animal’s health to make a decision that is best. And just like people, some animals can handle stress better than others. Some animals may never get sick, while others may get sick multiple times.

bulls at bunk
Young bulls eating at a bunk feeder.

Let’s talk more about cattle being fed antibiotics to control liver abscesses. Liver abscesses are caused by grain intake and consumption; these high energy diets require intense feeding management and can be associated with acidosis. A liver abscess is caused when cattle have an episode of acidosis. Acidosis is the most common nutritional disorder in the feedlot and can occur when cattle are fed high amount of grains in a short time, or when cattle overeat (regardless of the feedstuff). This results in the production of more lactic acid than can be buffered by the rumen, water from the circulatory system is drawn into the rumen, resulting in a change in pH. Dr. Dee Griffin, DVM (Doctor of Veterinary Medicine), says there are many reasons cattle overeat, but one of the more common reasons is a decrease in barometric pressure. Cattle can sense a storm coming, and will eat more than usual, if that diet is high in energy (i.e. grain) it may result in an acidosis event. Dr. Griffin says that when the pH in the rumen falls below five, certain bacteria can cross the rumen into the liver resulting in a liver abscess. To help control the abscesses, an antibiotic called Tylan can be fed to cattle in their feed.  It is estimated that at least 75% of cattle in feedlots are fed Tylan. Tylan helps reduce liver abscesses by 40-70%! As I mentioned above, this is an individual beef farmer’s decision.

Breakfast is served!

Stay tuned for Part 2 of the Antibiotic Resistance discussion…

Meet…Willow Holoubek

What does Agriculture mean to You? A new series in which I hope to show you that the definition of agriculture is as diverse as the people who work and play in it are. Enjoy! Earlier you met Dr. Dee Griffin, today I want you to meet Willow Holoubek, Executive Director of A-FAN (Alliance for the Future of Agriculture in Nebraska).




Meet…Dr. Dee Griffin

What does Agriculture mean to You? Is a new series in which I hope to show you that the definition of agriculture is as diverse as the people who work and play in it are. Enjoy!

Meet Dr. Dee Griffin, Feedlot Production Management Veterinarian and Professor at Great Plains Veterinary and Educational Center