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Our Big Pig Problem

The U.S. should follow Denmark and stop giving farm animals low-dose antibiotics















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The Crisis of Antibiotic Resistance Bacteria are finally overrunning our last defenses. Can we stop them?  » February 8, 2012



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For more than 50 years microbiologists have warned against using antibiotics to fatten up farm animals. The practice, they argue, threatens human health by turning farms into breeding grounds of drug-resistant bacteria. Farmers responded that restricting antibiotics in livestock would devastate the industry and significantly raise costs to consumers. We now have empirical data that should resolve this debate. Since 1995 Denmark has enforced progressively tighter rules on the use of antibiotics in the raising of pigs, poultry and other livestock. In the process, it has shown that it is possible to protect human health without hurting farmers.

Farmers in many countries use antibiotics in two key ways: (1) at full strength to treat animals that are sick and (2) in low doses to fatten meat-producing livestock or to prevent veterinary illnesses. (It is illegal in the U.S. to sell milk for human consumption from dairy cattle treated with antibiotics.) Although even the proper use of antibiotics can inadvertently lead to the spread of drug-resistant bacteria, the habit of using a low or subtherapeutic dose is a formula for disaster: the treatment provides just enough antibiotic to kill some but not all bacteria. The germs that survive are typically those that happen to bear genetic mutations for resisting the antibiotic. They then reproduce and exchange genes with other microbial resisters. Because bacteria are found literally everywhere, resistant strains produced in animals eventually find their way into people as well. You could not design a better system for guaranteeing the spread of antibiotic resistance.

The data from multiple studies over the years support the conclusion that low doses of antibiotics in animals increase the number of drug-resistant microbes in both animals and people. As Joshua M. Sharfstein, a principal deputy commissioner at the Food and Drug Administration, told a U.S. congressional subcommittee last summer, “You actually can trace the specific bacteria around and ... find that the resistant strains in humans match the resistant strains in the animals.” And this science is what led Denmark to stop subtherapeutic dosing of chickens, pigs and other farm animals.

Although the transition unfolded smoothly in the poultry industry, the average weight of pigs fell in the first year. But after Danish farmers started leaving sows and piglets together a few weeks longer to bolster the littermates’ immune systems naturally, the animals’ weights jumped back up, and the number of pigs per litter increased as well. The lesson is that improving animal husbandry—making sure that pens, stalls and cages are properly cleaned and giving animals more room or time to mature—offsets the initial negative impact of limiting antibiotic use. Today Danish industry reports that productivity is higher than before. Meanwhile reports of antibiotic resistance in Danish people are mixed, which shows—as if we needed reminding—that there are no quick fixes.

Lest anyone argue that Denmark is too small to offer a reasonable parallel to the U.S., consider that it is the world’s largest exporter of pork. Like U.S. farmers, Danes raise pigs on an intensive, industrial scale. If they can figure out how to limit antibiotic use while actually increasing agricultural productivity, then so can Americans.

The American Medical Association, the Infectious Diseases Society of America, the American Public Health Association, a previous FDA commissioner and many others have advised the U.S. to follow suit. Last year the FDA published new guidelines calling for “judicious use” of antibiotics. Yet it ultimately left the decision on exactly when and where to use antibiotics up to individual farmers. That laissez-faire standard is not good enough, particularly when the health of the rest of the population is at stake.

Of course, the way veterinary antibiotics are used is not the only cause of human drug-resistant infections. Careless use of the drugs in people also contributes to the problem. But agricultural use is still a major contributing factor. Every day that passes brings new evidence that we are in danger of losing effective antibiotic protection against many of the most dangerous bacteria that cause human illness [see “The Enemy Within,” by Maryn McKenna=]. The technical issues are solvable. Denmark’s example proves that it is possible to cut antibiotic use on farms without triggering financial disaster. In fact, it might provide a competitive advantage. Stronger measures to deprive drug-resistant bacteria of their agricultural breeding grounds simply make scientific, economic and common sense.



This article was originally published with the title Our Big Pig Problem.



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  1. 1. aseifer 02:35 PM 3/24/11

    Re: Henry Fountain, "Marijuana Ingredient May Fight Bacteria, The New York Times, Sept. 9, 2008.

    The article cited states: "Researchers in Italy and Britain have found that the main active ingredient in marijuana — tetrahydrocannabinol, or THC — and related compounds show promise as antibacterial agents, particularly against microbial strains that are already resistant to several classes of drugs."

    Has there been any further development regarding this claim?

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  2. 2. Toucanfoods 11:57 AM 3/28/11

    With this type of evidence to the benefit of ending or at least significantly reducing the use of antibiotics on farms, lack of action by big ag should make one suspicious of the relationship between them and big pharmaceuticals. According to Ralph Loglisci at the Center for a Livable Future, 80% of all antibiotics used in the U.S. are used in agriculture. That would be a huge reduction in sales for some pharmaceuticals manufacturers.

    Teresa Harlow
    www.toucanfoods.com

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  3. 3. raylindairy 12:55 PM 3/29/11

    (It is illegal in the U.S. to sell milk for human consumption from dairy cattle treated with antibiotics.)

    The above statement would be more accurate if it was to read: "It is illegal to sell milk for human consumption that that tests positive for antibiotics. Milk from animals treated with antibiotics is segregated from the human food supply on farm until for a period of time known as the "withholding period".

    The Pasteurized Milk Ordinance (PMO) is the law that governs antibiotics in milk among other things.

    Ray
    www.raylindairy.com

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  4. 4. jakito 07:14 AM 3/30/11

    As I recall it, a campaign with this very effective poster sparked the whole initiative:
    http://www.dn.dk/Default.aspx?ID=2372&PID=10482&NewsID=1891
    The text says: "Danish pigs are healthy. They burst with penicillin".

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  5. 5. tharriss 07:38 AM 3/30/11

    Well End of Days is coming soon anyway, so why worry about "possible" super bugs, and anyway God would never let a bug hurt us.

    Plus, we should let the corporate farmers make as much money as possible without regard to hurt to the environment or any other "mythical" damage that the liberals always yammer about... everyone needs to maximize profits as much as possible until God comes to take us all to Heaven!

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  6. 6. shonny61 10:11 AM 3/30/11

    This story is at best uninformed, at worst propaganda.

    The very low dose "antibiotics" used as growth enhancing agents in meat animals are a class of compounds called ionophores. While their mechanism of action, distrupting cell membrane transfer, can be described as bacteriostatic, these compounds are not used as antibiotics in humans. Therefore, the purported but unproven bacterial resistance to ionophores would not cause resistance to antibiotics used to treat humans.

    Not mentioned in the story is the fact that MRSA resistant strains of bacteria found in hogs in Iowa and Denmark (and widely reported as "proof" that ionophores were causing an outbreak of antibiotic resistance) were found to have been transmitted to the animals by human workers, who had picked up the MRSA in hospitals, which happen to be the number one breeding ground for antibiotic resistance, for obvious reasons.

    This whole theme of farmers posing an existential threat to humanity is fear-based nonsense peddled by uninformed and scientifically illiterate journalists and assorted "fear-fad" hangers on. It is very similar to the completely debunked conspiracy theory that human vaccines cause autism.

    Readers should peruse sensational stories with a healthy dose of skepticism and do their best to sort fact from fiction.

    For a story regarding a point-by-point rebuttal of Katie Couric's sensationalistic "investigation" of the same subject, visit http://prairieadventure.blogspot.com/2011/03/food-animals-and-antibiotic-resistance.html

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  7. 7. Cypher 10:16 AM 3/30/11

    The use of antibiotics may not be the boon we once thought it was, particularly since many are known to upset the microbiome ecology in an animals systems. It appears that the most healthful advice is to maintain a balanced microbiome ecosystem, rather than inhibiting specific bacteria. Until more is known regarding the nature of the chemical composition of communication between various bacterial "colonies" and exactly what the ideal balance is, I remain very skeptical about "magic [pharmaceutical] cures" for any particular issue. The March 2011 issue of Discover contains a good starting point for understanding the current research into microbiomes. (c.f.: http://worldmags.net/science_related/5453-discover-magazine-march-2011.html)

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  8. 8. adelray 01:37 PM 3/30/11

    A few years ago after seeing a weird advertisement for something (that looked like the Norplant birth control system) that could increase growth in cattle-I went on a personal mission to find the answer to the question, "what exactly is in our meat?" I was completely shocked.

    After reading this article, I noticed it was a lot more difficult to view feed ingredient listings online than it was before...hmmmm. Too many questions?

    For Pork, don't forget the ractopamine hydrochloride (sp?) which honestly, I can't even remember what it's supposed to do. I have seen antibiotic ingredients listed in some hog feeds no mention of derivatives...straight up antibiotics.

    Animals are not meant to be raised for mass production, factory style...in doing so, we put animals and humans at risk for outbreaks of any kind. Keeping them medicated to fatten them up is just plain corrupt and using antibiotics to accomplish the same is even more corrupt.

    If people want their food supply to remain safe, then animals should be raised as naturally as possible, the way they were intended to be....If you Frankenstein anything long enough, it will come back and bite you sooner or later.

    At some point, common sense HAS to outweigh greed, right?

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  9. 9. jgrosay 01:57 PM 3/30/11

    The time for banning antibiotics in animal food is now!

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  10. 10. vagnry 02:42 PM 3/30/11

    Banning antibiotics is not enough, farmers (at least in Denmark, I am Danish) couldn't care less about what is legal and what is not, they illegally import fertilizers (beyond the legal limits), antibiotics, etc.

    At the same time, they are getting the highest subsidization of any group in the European Union, without subsidies more than 90% would go bankrupt!

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  11. 11. scientific earthling in reply to shonny61 07:41 PM 3/30/11

    Ionophores are antibiotics that were originally developed as coccidiostats (an antiprotozoal agent that acts upon Coccidia parasites) Ref: http://animalscience.tamu.edu/ansc/beef/ANSC406/Prince,S.pdf
    Don't hide the truth behind words most people might feel intimidated by.

    What this article does not say is: DNA and RNA are templates that generate proteins. They result in the bottom up generation of every living organism. Bacteria do not reproduce sexually, but they also need to renew their genetic codes, they do this by borrowing segments of each others DNA, the surprising thing is they borrow across species barriers and even from dead bacteria (DNA/RNA are not living molecules). This makes immunising bacteria against antibiotics all the more dangerous.

    Sadly I find myself agreeing on one point, with the god person, end days are coming for the Homo sapien, sadly no afterlife follows. The end days are the result of his/her own doing, essentially breeding out of control and destroying habitat. The earth will still exist and life will blossom again after the sixth extinction has run its course.

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  12. 12. juxtapose82 12:48 PM 3/31/11

    Where to begin today? Ok number one, if the end of days are coming and you believe that there is no time left to worry about our food supply, well then good luck with that. I dare you to live like what you preach is true.

    Second, I doubt the propaganda just because we understand that bacteria, viruses and parasites are all known to mutate (some faster than others) once we find ways to kill them. Lets not forget about the polio warning that the old vaccines are probably no longer effective due to several mutations.

    Thirdly, I think the push should maybe come from a new angle. I'm sure some of you are familiar with phage research going on now. An actual killer of the little baddies. They would operate as more of a 'booster' to the immune system instead of weak practice run of disease recognition that could very well look completely diffeernt in 20 years. Maybe the answer is to actually find something that has an evolutionary path that will 'genetically' keep up in the micro arms race and continue its effectiveness for a long time to come.

    Lastly, I have to revert back to my first paragraph, do people really think that God won't let us get wiped out by a bug even after the plague? The only way we pulled any survivors from that was a mutation in some humans genetics. Now, I am not saying that it is unfathomable that God worked that into some grand plan but, lets say that we are created in his likeness. Then a mutation is not part of his (or her) plan because our bodies exercised their own 'free will' and parted company with the original blue print. So that being the case, God's intention was to kill mankind with a super bug and failed only because mankind deviated genetic makeup.

    I know that I am going to get a lot of hate mail on this last part but it makes me scared that people might base decisions for all of us off of religious faith instead of what actually happens. I am not questioning that your faith is righteous or not, just don't make scientific solutions with it.

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  13. 13. ljrphoto in reply to shonny61 04:16 PM 3/31/11

    It is simply not true that ionophores are the only "antibiotic" used in meat production.

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  14. 14. scientific earthling in reply to juxtapose82 05:58 PM 3/31/11

    Juxtapose82: This is not a god forum. It is useless to appeal to the god people. They have closed minds, if we can call them minds at all.
    It is the god people who are the driving cause of the sixth extinction. However if you study the universe that surrounds us, it is imperative life would have evolved elsewhere, some where intelligent societies would have developed, a lot earlier than here on earth. We see no hint of these societies. It is reasonable then to conclude that societies like ours always bring on their own extinction. As we have done in less than 200 years.

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  15. 15. Wayne Williamson 03:49 PM 4/3/11

    se...count me as one of those that is not counting on a supreme being to come and rescue us...we got ourselves into this mess and we better get ourselves out of it....

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  16. 16. boyah 07:41 AM 4/15/11

    Pigs are disgusting filthy creatures that should phased out of our food chain. For everyones good.
    They are not worth the problems they create. Theres way to many other healthy things to eat, they would not be missed!

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  17. 17. bewertow in reply to tharriss 10:50 PM 8/15/11

    thariss, I think you are retarded.

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