THEGREENGROK    Statistically Speaking

Statistically Speaking: Pigs by the Numbers

by Bill Chameides | March 13th, 2009
posted by Erica Rowell (Editor)

Permalink | 2 comments


Pigs are darn cute, don’t you think? But overcrowding them may not be so cute. (Wikimedia: titanium22)

New York Times columnist Nicholas D. Kristof has a great little series on the link between our food, pigs in this case, and our health. What’s the connection and why?

In a word, antibiotics. Antibiotics have allowed us to use practices that maximize profits and minimize consumer costs by crowding more animals into smaller, controlled spaces. Such living conditions make livestock more susceptible to disease and infection — unfortunate “byproducts” that producers combat by prophylactically feeding the animals antibiotics.

The problem is that the more antibiotics we feed pigs or other livestock, the more resistant the bacteria we’re trying to eradicate become. Sometimes those bacteria jump from livestock to people, and then we have even bigger problems.

Size Counts: Number of Pigs Then and Now

The U.S. Department of Agriculture’s Agricultural Census gives an estimate of just how much crowding of America’s pigpens has occurred over the last decade.

Number of pigs in the United States in 1997: 61.2 million
Number of pigs in the United States in 2007: 67.8 million
Approximate number of pigs per acre of U.S. farm in 1997: 4.3
Approximate number of pigs per acre of U.S. farm in 2007: 8.7

In other words, we’ve taken about the same number of pigs and crammed them into half the space.

What a Waste

Oh, and if you’re wondering about other, er, byproducts from raising hogs …

Estimated tons of pig waste produced by a 250-pound hog by the time it’s ready for the slaughterhouse: 1.5 *
Estimated tons of pig waste per year produced by North Carolina’s hog factories, in 2000: 19 million **
Estimated tons of solid waste produced and tossed by the average person in the United States yearly: .75 ***
Approximate tons of pig waste per North Carolina citizen per year: 2.5 **

Notes – Pig per acre calculations are based on a subset of farms that use the North American Industry Classification System. Total farm acreage is used. This subset captures more than 80 percent of the pigs tracked by the USDA Agricultural Census.

Additional Sources

*    NC Sustainable Energy Association
**  Environmental Defense Fund [pdf]
*** Municipal Solid Waste in the United States [pdf]

Pigs vs. Hogs
Ever wonder what’s the difference between a pig and a hog? In lots of countries they mean the same thing, but to the U.S. swine industry (and to the U.S.D.A.) a pig weighs less than 120 pounds whereas a hog weighs more.

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  1. Daniel Wedgewood
    Mar 25, 2009

    Ever try to catch a pig? I don’t mean the greased up kind at county fairs, but rather those of the “hog” variety. The more space you give them, the more room they have to run you to death. They are fast, clever, sneaky, and will drag you like a rag doll if you do happen to catch one. They are also low to the ground, which makes the whole process much harder. And, once caught, they will screech loud enough to burst your ear drums. Go for broccoli instead – it’s safer, grows faster, and will not bite you… and no cholesterol. Dan

    • Bill Chameides
      Mar 27, 2009

      Dan – I can’t say that I have ever tried to catch a pig, but will take your advice.

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