Reducing antibiotic use in calves

By Lilian Schaer, Agricultural Writer  

Antimicrobial medications are widely used to fight bacterial infections in both humans and animals. Resistance happens when bacteria and other microorganisms evolve so that they are no longer affected by the medications used to treat them. This makes it much harder to protect people and animals against infections—and it’s an issue of growing concern right around the world.

Currently, antimicrobials are widely used in calf production in Canada. For example, a large number of calves are given antimicrobials for diarrhea and pneumonia both before and after weaning, even if that might not be the most appropriate course of treatment.

Canada and other countries around the world have been tightening the rules around the use of antimicrobials in livestock production to ensure products are being used responsibly and preserve their value for use in human medicine. And although it is always important from an animal welfare perspective to treat calves with the proper medications when they are sick, there are many other ways to prevent disease and control infection.

Establishing a good veterinarian-client-patient relationship is an important part of managing animal health in your herd. Not only is this a requirement in order to receive prescriptions for medically important antimicrobial drugs, but a veterinarian can help you identify and solve a wide range of calf performance issues.

A good place to start is with the five Rs: responsibility, reduction, refinement, replacement, and review.


Work with your veterinarian to develop solid protocols or standard operating procedures that spell out how you will treat or manage specific health conditions in your calves. Not only does this ensure consistent treatment, but it also boosts efficiency and ensures food safety.

Maintain accurate and detailed drug treatment records to help manage withdrawal times, avoid residues and track how well treatments are working. These can be simple, handwritten notes in a binder or recorded in herd management software.


The best way to reduce antimicrobial use is to keep animals healthy—and key to that is focusing on disease prevention through biosecurity. A good biosecurity plan controls who and what comes onto your farm, whether that’s new animals entering the herd, outside visitors, or even equipment and supplies like feed that could bring disease onto the farm. It also spells out practices for managing everything from keeping sick animals separate from healthy ones, cleaning and disinfecting strategies, dealing with rodents, and keeping good records. 

Good day to day care of calves is also important. This includes maintaining stocking densities, good ventilation, balanced nutrition, and early disease detection.


When you do have to use antimicrobials, the goal is to use them so they’re as effective as possible. This means using the right drug for the right condition at the right time in the right dosage. Your veterinarian is your best resource for success.

Tip: try using a treatment flow chart to determine when antimicrobials might be the most effective treatment option.


Ultimately, you want to find areas where you can replace antimicrobials with other ways to treat or prevent disease. This includes using vaccines, or emerging technologies such as pre- or probiotics, bacteriophages, engineered peptides or immune stimulants. Building disease resistance through breeding is also becoming easier thanks to improvements in genetic technology.


Reviewing your tools and techniques is an important part of continuous improvement. That’s why monitoring and recording things like the level of antimicrobial use on your farm; the reason, date, and type of treatment; and the animal’s response will help you fine tune your animal health management.

This project was funded by the Canadian Agricultural Partnership, a five-year federal-provincial-territorial initiative.