Antibiotic-Free Pigs Carry More Pathogens, But is That a Bad Thing?

By Andrew Moseman | June 12, 2008 4:11 pm

Should pigs recieve antibiotics?Advocates of “organic” or “natural” foods get up in arms about some of the practices at big commercial hog farms—especially putting antibiotics into the livestock feed to make the animals grow faster. The idea simply makes some people uncomfortable, but more importantly, the overuse of antibiotics in animals, just like in hospitals, can worsen the problem of antibiotic resistance in bacteria. According to a study out of Ohio State University, however, pigs that went without antibiotics were more likely to carry human pathogens like salmonella and trichinella.

The team of scientists led by Wondwossen Gebreyes studied around 600 pigs. About half lived in indoor commercial hog farms and received antibiotics; the other half lived the old-fashioned way, outdoors and antibiotic-free. The non-treated swine showed more salmonella infections, 54 percent compared to 39 percent of the treated pigs, and more infections of toxoplasma and trichinella.

At first, it might appear that we’ve reached an impasse: If we keep pumping livestock full of antibiotics, bacteria will continue to become more resistant and we’ll lose our best weapons against them, but if we stop giving livestock antibiotics, our meat will be more dangerous, so pick your poison.

However, these two scenarios are not equal. The first one, antibiotic resistance, could be much worse—if a person gets a bacterial infection that’s resistant to any known antibiotic, there’s not much a doctor can do. But as far as more food-borne pathogens are concerned, whether 39 percent or 54 percent of pigs carry salmonella, all it takes to kill the bacteria is cooking your pork chops all the way through—the U.S. Department of Agriculture recommends at least 160 degrees Fahrenheit.

Still, these food-borne pathogens are nothing to be trifled with. Salmonella infects 1 million Americans each year, whether through undercooked meat or outbreaks in fruits or vegetables, like the current tomato scare. Trichinella can make people terribly ill. But if the choice is between microbes we can kill pretty effectively and microbes we might not be able to, it’s an easy one.

As the Des Moines Register asked last month, people in good health shouldn’t be taking antibiotics, so why should we put them in the food of perfectly healthy hogs? We probably shouldn’t.

  • Kristina

    This is absolutely true. Our society has become too obsessed with antibiotics and disinfection, overspraying our homes with Lysol and swallowing antibiotics for every minor illness. We are creating our own worse biological enemy.

  • Ricahrd

    Without getting into the argument of whether antibiotic resistance is worse than food poisoning or the reverse, or even if resistance in animal bacteria is a threat to humans the author’s point regarding control contains very flawed logic. The point that cooking meat controls food poisoning is correct – but it is also prevents resistance transfer. Cooked salmonellae neither cause food poisoning, nor present any antimicrobial resistance hazard.

    As for Trichinella and other pathogens in the open environment, these may be an additional hazard from free-range food. They are controlled by housing the animals.

    In summary: The two farming scenarios are not equal. Cooking is always good and controls bacteria and any potential antibiotic resistance transfer. Food from non-housed animals may present additional risks over housed animals.

  • johnk

    in view of these substantial disease problems in the ag-industry, it simply amazes me that with AVAILABLE, cost-effective, ALL-NATURAL alternatives to antibiotics — with demonstrated positive results, in test after test — there is not a larger (total?) acceptance of these products. i readily admit that i am not an expert in this field … so, i am looking for the “expert” to tell me why such products are not being used. (note: i have heard from many non-experts all of their speculation of why this is so. i thank them, in advance, but respectfully request that they not respond to this querry. i am interested in the factual answers from the “experts”. not speculation).

  • Pingback: Better Meat Through Bach: Classical Music Makes Piglets Less Stressed | Discoblog | Discover Magazine()


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