Page 51 - RealDirtENG2020

Health Canada has established four categories of antimicrobials based on how they are used in human medicine, ranging from Category I (“very high importance”) to Category IV (“low importance”)116. The Canadian government tightened the rules on antimicrobial use in farm animals in 2018. For example, farmers now need a veterinary prescription to buy any Category I, II, and III products, and using any of these products to promote growth has been banned117. Advances in animal housing, nutrition, and biosecurity practices mean that fewer antibiotics are used today than in past decades.
The bottom line on antibiotics
Antibiotics are a valuable tool for treating sick people and animals, so it is important that everyone uses them responsibly. Resistance is a complex topic, and critically important research into resistance is happening around the world in both human and animal medicine.
Ciara Sandum
Common question: antibiotics and resistance
Antibiotics are a type of antimicrobial medication used to ght bacterial infections in people and animals. Antibiotic resistance occurs when the bacteria change and develop the ability to survive exposure to the antibiotics used to treat them. As a result, the medication is no longer effective in killing or slowing the growth of a speci c disease-causing organism. It’s an important issue worldwide, because it makes it harder to ght human and animal infections caused by these resistant bacteria.
Antimicrobial resistance is a natural phenomenon114 which can be made worse by environmental contamination, misusing antibacterial cleaning products, and using antibiotics in human or animal medicine too much or incorrectly115.
Career Pro le
Veterinarian
Dr. Cali Lewis
With veterinarians for parents, it’s no wonder that Dr. Cali Lewis would choose to become
one herself. Lewis has been practicing in her hometown of Westlock, Alberta, since 2015. She practices both small and large animal veterinary medicine, meaning she works with pets, as well as livestock, such as horses, goats, sheep, and cattle.
She enjoys working closely with farmers
on their animal care strategies. “The key
is to focus on preventative measures like strong vaccination protocols, limiting stress and providing good nutrition. But antibiotics certainly have their place when needed.”
Lewis describes working with farms as a challenging yet gratifying puzzle. “In addition to caring for the individual animals, you also have to consider the health of the entire herd, as well as economical and production factors. It’s de nitely a big picture approach to veterinary care,” said Lewis.
In her free time, she can be found riding her horse, Sadie, hiking or paddle boarding with her dog, Steady, and partaking in all things outdoors.
Chapter 7: Healthy and safe food 51
What about drug residues?
Drug residues are traces of medication left over in meat, milk, or eggs, after an animal has been treated with a medication. Every animal health product (e.g. antimicrobials, vaccines, supplements) has what is called a “withdrawal period”—a speci c amount of time a farmer must wait before sending a treated animal or its products to market118. This ensures that food is safe and free of residues. As an added layer of security, processing plants also test for drug residues to ensure food safety.