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    Every Creeping Thing: True Tales of Faintly Repulsive Wildlife: “Conniff is a splendid writer–fresh, clear, uncondescending, and with never a false step; one can’t resist quoting him.” (NY Times Book Review)

    The Species Seekers:  Heroes, Fools, and the Mad Pursuit of Life on Earth by Richard Conniff is “a swashbuckling romp” that “brilliantly evokes that just-before Darwin era” (BBC Focus) and “an enduring story bursting at the seams with intriguing, fantastical and disturbing anecdotes” (New Scientist). “This beautifully written book has the verve of an adventure story” (Wall St. Journal)

    Swimming with Piranhas at Feeding Time by Richard Conniff  is “Hilariously informative…This book will remind you why you always wanted to be a naturalist.” (Outside magazine) “Field naturalist Conniff’s animal adventures … are so amusing and full color that they burst right off the page …  a quick and intensely pleasurable read.” (Seed magazine) “Conniff’s poetic accounts of giraffes drifting past like sail boats, and his feeble attempts to educate Vervet monkeys on the wonders of tissue paper will leave your heart and sides aching.  An excellent read.” (BBC Focus magazine)

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The Man Who Turned Antibiotics Into Animal Feed–Post Script

Posted by Richard Conniff on March 10, 2014

hogNeither industry nor regulators ever conducted a proper large-scale long-term study to test whether the growth promotion Thomas H. Jukes reported was a lasting effect. Even 60 years later, researchers are only beginning to make up for this remarkable omission.

In 2007, researchers at Johns Hopkins University analyzed industry data and found that, while antibiotics produced a slight weight gain in chickens, the cost exceeded the resulting commercial benefit. A 2010 study by the US Department of Agriculture likewise found “no statistically significant impact on production” in broiler chickens, and another USDA study in 2011 found significant gains in nursery pigs, but none in animals close to market size.

Data from Denmark and Sweden, where the use of antibiotics in food animals is restricted, clearly show that tight control of the practice “does not lead to long-term negative effects on industry”, says Tyler Smith, a researcher at The Johns Hopkins Center for a Livable Future. “We are squandering a medical miracle on the basis of very limited evidence that it is necessary to produce animals,” he says.

If antibiotics do boost weight gain, even temporarily, how might it happen? Do they inhibit “bad” bacteria that would otherwise impair growth? Do they slow microbial metabolism, freeing up more nutrients for the host animal? Do they thin the intestinal walls or otherwise make it easier for the animal to absorb nutrients? Nobody knows for sure.

One promising development for livestock producers and health advocates alike is that new genetic insights into an animal’s “microbiome” – the microbes that colonize its gut and other niches – may provide far more exact answers to these questions. Livestock producers are already testing beneficial bacteria and other mechanisms to tweak the bacterial processes in an animal’s gut. In one case, using “good” bacteria to crowd out “bad” ones, a strategy called competitive exclusion, reduced the salmonella load in factory-reared turkeys by 90%. That kind of precise control could soon render subtherapeutic antibiotics in animal feed irrelevant.

One Response to “The Man Who Turned Antibiotics Into Animal Feed–Post Script”

  1. Nancy said

    Reblogged this on "OUR WORLD".

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