One of the most revolting things I learned while researching my new book "Animal Factory" is that some cattle are fattened on rations that include chicken manure. Poultry excrement is loaded with urea, which bovine stomachs are adept at converting into lean, ready-to-grill protein.
We feed chicken manure to cattle because it's cheap; and because we produce far too much of it to properly dispose of as fertilizer.
Today's "broiler" chickens are raised at record speed in massive, mechanized barns that cram tens of thousands of birds into a single confinement. Broilers live just eight weeks. But in that short time, their endless fecal droppings (birds don't urinate) mix into a bedding of woodchips and other material, yielding a thick "cake" of litter that's scraped from the barn after each flock is removed.
What becomes of all that feculence? Its nitrogen and phosphorous content is so high that land application uses are limited. In Maryland's Eastern Shore, litter runoff is helping to fuel fish-choking algal blooms. In Arkansas, traces of arsenic (a growth-promoting feed additive) were found in homes near cropland onto which pulverized litter was spread.
So why not convert that chicken dung into Chateaubriand?
To begin with, cattle were meant to eat grasses, not feces (nor corn, soybeans or other subsidized commodities). But there's another reason why chicken litter should probably be kept away from cattle.
Poultry feed often contains bits of rendered beef byproducts. Chickens are not tidy eaters: they spill copious amounts of food into their litter, which is then fed to cattle. And, as everyone knows, cows that eat cows can go "mad" with bovine spongiform encephalopathy (BSE, or spongy cow-brain disease).
In 2004, the FDA proposed banning poultry litter in cattle feed, to avoid the spread of BSE. It was already outlawed in Canada. But days later, the agency postponed its change, citing "troubling feedback" from the agricultural sector. Some foreign countries balked at buying US beef, but the Bush Administration held firm, refusing to commit to a deadline.
Chicken litter is not the only way that American cattle eat cattle. Beef-containing restaurant scraps are often rendered into feed, and a formula for dairy calves (whose mothers' milk is deemed too valuable to "waste") contains bovine blood products.
I imagined that the Obama Administration would complete the work left undone by Bush and enact a universal ban on feeding beef products to cattle. Instead, I discovered that Obama's FDA had ratified what his predecessor proposed: Doing nothing.
Well, not exactly nothing. In April 2008, Bush's FDA published its final rule on "Substances Prohibited From Use in Animal Food or Feed," which took effect under Obama's FDA, in April 2009.
"FDA is amending the agency's regulations to prohibit the use of certain cattle origin materials in the food or feed of all animals," it wrote in the Federal Register. These include: "the entire carcass BSE-positive cattle; the brains and spinal cords from cattle 30 months of age and older; the entire carcass of cattle not inspected and passed for human consumption that are 30 months of age or older from which brains and spinal cords were not removed; tallow that is derived from BSE-positive cattle; (and) tallow that is derived from other materials prohibited by this rule that contains more than 0.15 percent insoluble impurities."
Feel better? The agency insists that BSE "prions" (deadly, deformed proteins) are only found in brains, nerve tissue and spinal cords, and not in muscle or blood. Since none of those are allowed into any animal feed, it's ok to feed cattle to cattle, FDA says, and there's no need to ban litter, table scraps or blood products.
"A cow would need to consume a very large volume of poultry litter to ingest an infectious dose of BSE," it wrote. "FDA believes that the risk of cattle exposure to an infectious dose of BSE through poultry litter is low," and that banning the above-mentioned materials "should reduce that risk even further."
In other words, it's possible, but we really don't think it will happen that often.
As for table scraps, "FDA disagrees that it is necessary to eliminate the plate waste exemption because, since 2004, human food has been required to be free of SRMs," (specified risk materials).
FDA also refused to ban blood products, even though infective prions were "demonstrated experimentally in the blood of sheep and rodents." Species differences, it argued, "suggest that these findings cannot necessarily be extrapolated to cattle."
And then came this rather unsettling statement: "While FDA agrees that more sensitive detection methods might some day demonstrate BSE infectivity in bovine blood, the agency believes that it is highly unlikely that the BSE agent is present in blood of infected cattle at levels sufficient to transmit disease."
In other words, if you can't test for it, why worry about it?
Personally, I'm not sure if "highly unlikely" is reassuring enough. Besides, if we can't produce food without giving feces, blood and old meatloaf to cattle, there's something seriously wrong with our system.
David Kirby is author of "Animal Factory: The Looming Threat of Industrial Pig, Dairy and Poultry Farms to Humans and the Environment" (St. Martin's Press): More info at www.animalfactorybook.com