04/07/2014 01:27 EDT | Updated 06/06/2014 05:59 EDT

Should Sick Animals Be Treated With Antibiotics?

The current debate over antibiotic use on animals is rampant and has caused many alarmed consumers to demand antibiotic-free meat. Companies like McDonald's are now only buying from suppliers that limit antibiotic use in their animals.

The U.S. Food and Drug Administration just convinced 25 drug companies to stop producing antibiotics for animals that are used in human medicine and reduced the available supply of these drugs by 99.6 per cent. Many believe Canada should follow suit.

Clearly, it is humane to treat sick animals, but harm can come to humans if animal antibiotic use develops drug-resistant bugs that subsequently infect humans. While this is a legitimate and serious concern, three key factors -- antibiotic resistance, monitoring, and antibiotic residues --each play a decidedly different part in the story. It is important to understand these differences to grasp the full picture, and avoid evoking unnecessary fear.

Antibiotic resistance

The overarching issue is that, as microbes rapidly develop resistance, the prospect of humanity facing a future without antibiotics seems unavoidable. To some extent, the future already here as health authorities work to contain superbugs like MRSA or (TB) -- an airborne bacteria that has the potential to infect thousands.

The pace of new drug development has decreased, causing scientists to investigate alternative treatments, such as phages to treat infections, and revert to traditional measures.

Despite these concerning factors, it's important to note that bacteria-resistant bugs are contained in large part because not all animal antibiotics are used to treat humans, and certain drug classes can be used on animals without the risk of microbes developing resistance.

Furthermore, antibiotics are expensive so farmers don't use them needlessly and, when they do medicate their livestock, they ensure the full course of treatment is completed. We need to understand the broader context of animal antibiotic consumption before jumping to fear-filled conclusions.


Many worry that poor monitoring and lack of control over antimicrobial drug use in Canadian animals is contributing to the global problem of microbial resistance, consequently making widely-used drugs ineffective for humans who consume meat from sick animals treated by antibiotics.

While studies have shown that contaminated meat is, at times, retailed in Canadian supermarkets, the extent of the problem remains unknown. Health Canada is working to implement a nationwide, streamlined monitoring system to mitigate all contamination from bacteria resistant bugs.

Veterinarian associations are also calling for all jurisdictions to require prescriptions for producers to buy antibiotics, as is already the case in Quebec. This would aid in an integrated national monitoring strategy. These changes cannot come soon enough.

Antibiotic residues

While it's not impossible for antibiotic residues to make their way into the meat we eat, current Canadian Food Inspection Agency (CFIA) regulations require farmers to stop giving antibiotics to animals for specific time periods --depending on the drug -- before the animals are allowed to enter the food production process. Furthermore, meat processors treat antibiotics in incoming animals as a chemical hazard. They have systems in place, including routine lab testing, that ensure no detectible drug residues are present in inbound meat.

The meat and dairy industries are the most closely monitored segment of the food supply chain, because they enjoy the undivided attention of the CFIA and/or their provincial counterparts. Many production plants are required to have inspectors physically present on the line during operation.

Compulsory laboratory tests for residual antibiotics are routinely conducted prior to shipment. The development of residue detection technologies has been ongoing for over 70 years so these tests are well developed and reliable.

When compared with other sectors of the food industry, such as baby food production where companies many only be inspected every few years, poor monitoring is a non-issue for most Canadian meat producers.

To sum up

The majority of antibiotics produced are consumed by humans, not animals. Humans demand antibiotics for minor illnesses and often fail to complete treatment courses -- the key pathway to developing microbial resistance. It's fair to argue that drug-resistant bugs predominantly develop from human use of antibiotics, especially in hospitals.

The transfer of resistant bugs from humans to animals is also possible and likely occurs so we may well present a great risk to animals than they present to us. Therefore, when debating the use of antibiotics for sick animals, perhaps we should first look at our own misuse before withholding medical care from the animals entrusted to our care.


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