The Indiscriminate Use of Antibiotics in Livestock

By | June 01, 2013
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Antibiotics

We gotta get out of this place if it's the last thing we ever do

Bacteria are amazing creatures. They live on and in our bodies in such high volumes that bacterial cells greatly outnumber the human cells. Many of these bugs are harmless. Some of them actually contribute to human health by fighting off dangerous microorganisms or breaking down foodstuffs like cellulose that we can't metabolize on our own. Mitochondria were invasive bacteria for millions of years until they entered into a useful symbiosis with us as the tiny furnaces in our cells responsible for generating the energy that keeps us alive. Other microbes help us predigest foods, like those that ferment milk into cheese or tenderize meat. All things considered, we couldn't live without these creatures.

Most of us are much more familiar with bacterial pathogens—the bugs that make us sick. These are the nasty germs that invade our bodies and parasitize our tissues. They have the capacity to impair or destroy the immune defences which are aimed at protecting us from them. Some, like various species of streptococcus which cause strep throat, actually glom onto immune molecules and form toxic complexes that can slowly destroy joints, heart valves and kidneys. Others, like salmonella or botulinus, generate their own toxic compounds that lead to serious illness and death. Still others, like the mycobacteria and spirochetes, can smoulder within us for years, causing tuberculosis, leprosy or syphilis.

Until a relatively short time ago, bacterial infections killed more people than anything else. Bubonic plague, an infection caused by Yersinia pestis, which was spread by rats, wiped out about a third of the population of Europe in the fourteenth century. Viral respiratory tract infections—colds and influenza—set the stage for secondary bacterial infections like bronchitis and pneumonia that have taken the lives of countless people. Wound infections killed more soldiers than tissue damage and blood loss from spears, arrows, swords and bullets. Closer to home, my maternal grandfather died at age 35 of septicemia caused by a bacterial finger infection.

Our age-old struggle with bacterial pathogens took a sharp turn in our favour during the 1930s and '40s after British scientist Alexander Fleming noticed that something had eradicated the bacteria he was growing in a Petri dish. He soon discovered that the spore of a fungus called Penicillium, likely carried in the wind from Norway, had blown through his lab window and into the dish, where it produced a chemical that poisoned the bacteria. He named this substance Penicillin and the rest is history.

This antibiotic and another family of bug-killers known as sulfa drugs proved to be enormously successful in preventing and treating wound infections in soldiers during World War II. After the war these drugs became widely available and drastically reduced illness and death from bacterial infections that cause pneumonia, syphilis, gonorrhea, and a range of other diseases. Over the subsequent decades new antibiotics and new families of these drugs expanded the range of bacterial illnesses that could be wiped out with an injection or a course of pills. Doctors and the general public believed that we had eliminated the threat of bacterial infection and the sickness and death it produced.

In what was, for many of us, an unexpected and unpleasant surprise, bacteria have, over time, devised ways of resisting antibiotics. Some resistant organisms emerged because people stopped taking their antibiotics as soon as they felt better rather than completing their prescribed course of medication. This wiped out the wimpiest bacteria but spared the tougher ones that would have been knocked out by the full course, enabling them to produce offspring robust enough to resist treatment. The pharmaceutical industry responded with new products, but some bugs developed partial or total resistance to all of them. One of the most fundamental and life-saving tools in medicine has become endangered, and serious illness and death because of "superbugs" is on the rise.

It is now clear that agriculture has become a major source of antibiotic-resistant bacteria. How did we end up feeding copious quantities of antibiotics to major sources of our food supply and, it follows, to the consumers of the meat, poultry, eggs and dairy products that are derived from these sources? Much of it has to do with the proliferation of factory farms where multitudes of animals—from laying hens and broiler chickens to pigs and feedlot cattle—are confined indoors in close, often unsanitary quarters where disease can run rampant. And huge numbers of livestock farmers also started doing it because of empirical reports of faster growth in animals that received this treatment. Large-scale antibiotic dosing really took hold in the conventional livestock industry after the finishing of cattle on grass and forage was entirely supplanted by months-long routine finishing on corn and grains.

Corn is relatively inexpensive (except in time of drought, as we saw last summer) and energy dense. The cattle that eat it will use a lot of that energy to get really big really fast, getting them to market sooner and eliminating the cost of keeping them alive longer. But bovines biologically evolved to survive on a diet of grass. They, and their digestive systems, did not metamorphose to eat grain. The rumen, a 45-gallon bag in their digestive tract, allows them to draw nourishment from grass by fermenting it in an alkaline environment.

When cows fill their rumens with corn, some unpleasant and unfortunate things happen. For starters, ruminal bacteria react to the sudden presence of large amounts of rapidly fermented cereal grain by proliferating and generating a lot of acids. The acid causes impairment of the normal movement of the rumen. It also stimulates the production of lots of "slime"—technically, protein-sugar compounds known as mucopolysaccharides. This substance increases the viscosity of ruminal fluid, allowing it to be whipped into a stable froth that can kill cattle by crowding out their hearts, lungs and other vital internal organs.

Finally, corn feeding and the acidification of the rumen induces Uncle Morris-after-a-pastrami-sandwich-quality heartburn in cattle, which puts them off their feed. Eventually, especially in cows that have ingested too much corn too quickly, the acidity causes the rumen to ulcerate. Bacteria escape from the rumen into the blood stream and are carried by the hepatic portal vein to the liver, where they create liver abscesses.

Before long, cattle producers connected the dots: Each unwelcome outcome of corn feeding was brought about by bacterium. But instead of giving up on corn-fed, almost-instant mega-cows, they could feed their herds antibiotics to kill the bugs that were causing these problems in the first place!

That, in a rather large nutshell, is how intensive livestock operations and industrial farming have contributed to the generation of antibiotic-resistant bacteria which have already begun to seriously endanger our health. So is there anything that can be done about the problem?

There are some large-scale efforts under way. A recent report produced by the Ontario Medical Association recommends that government agencies strengthen surveillance of the farm industry and ban the prophylactic or growth-promoting use of antibiotics in animal husbandry. Letters and telephone calls to the appropriate elected and appointed officials can help. (Antibiotics are not indiscriminately used on organic farms. If an animal gets sick. antibiotics will be used as required to restore its health, but that animal is permanently removed from the organic-food-supply chain.)

More immediately, you could simply start asking your purveyors of meat, poultry, eggs and dairy products whether their products come from extensively corn-finished and/or antibiotic-doped animals, and buy only those that don't. (Because of the desirable marbling it creates, feeding moderate amounts of corn to cattle during the finishing stage prior to slaughter has become quite routine, even on some organic farms and, when done conscientiously, supposedly does not cause the animal undue harm.) Think of your dollar as a high-impact vote and keep it out of the hands of those looking for our bucks with absolutely no regard for our well-being.

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