We humans are great at making ethanol from grains. We’ve been doing it for thousands of years to make beer and liquor, and our expertise is one reason that corn ethanol has been the biofuel of choice so far. But the biofuels of the future, experts say, will come not from the starch in corn but from the cellulose in grasses and other abundant green plants. There’s just one problem: We’re not good at breaking down the tough structure of cellulose to get at the sugars inside.
But cows are.
Cows, like termites and leafcutter ants, love to eat tough plant material, and host bacteria with the molecular machinery to do so in their guts. Scientists, in their attempts to get better at breaking down cellulose, have tried to copy nature by studying the enzymes that allow those grass-eating animals to do their thing. And now researchers say they have found a treasure trove of new microbe-produced enzymes inside a cow that could help them in their quest.
In a study published Thursday in the peer-reviewed journal Science, researchers described how they incubated bags of switchgrass inside cow rumens and from that found 27,755 “candidate genes” with the potential for efficiently breaking down plant cellulose into usable sugar that can then become ethanol. [MSNBC]
Eddy Rubin and his team executed this chemical excursion by surgically opening a hole into the first of the cow’s four stomachs.
Goodbye and good riddance, rinderpest.
For only the second time in history, humans have eradicated a disease through a long, slogging campaign of vaccinations and global alertness.
Rinderpest, which means “cattle plague” in German, does not affect humans, though it belongs to the same virus family as measles. But for millenniums in Asia, Europe and Africa it wiped out cattle, water buffalo, yaks and other animals needed for meat, milk, plowing and cart-pulling. Its mortality rate is about 80 percent — higher even than smallpox, the only other disease ever eliminated. [The New York Times]
For years, farmers in Kenya’s arid north have suffered huge losses when droughts wiped out their cattle herds. Now, they have a means to protect their sole source of livelihood when rains fail and grasslands disappear. A new insurance scheme hopes to safeguard cattle-rearers in northern Kenya’s drought-prone Marsabit district by using satellite imagery to track changing landscapes and the subsequent loss of cattle.
The program, launched by the International Livestock Research Institute, is being billed as the world’s first insurance program to track changing pastoral grounds. When the satellite photos reveal that a verdant green landscape has changed to a dry brown, the insurance kicks in and farmers can collect their payments. The program will make things easier for insurance companies–for whom estimating losses in the past has been all but impossible. Partly because it has simply been too expensive for insurers to go and count the number of dead animals which might be spread over a vast rural area [BBC]. The scheme’s launch comes at a time when the Marsabit region has suffered 28 droughts in the last 100 years and four in the past decade alone [Kenya Broadcasting Corporation].
It’s not just humans who can take part in combating global warming–cows can play a role, too. Scientists say that the methane belched up by cows is a significant source of the greenhouse gas, and are searching for ways to reduce these burps. The digestive bacteria in the cows’ stomach produces the methane, which is the second-most significant gas (behind carbon dioxide) driving global warming. While methane is much less prevalent in the atmosphere than carbon dioxide, it traps heat 20 times more efficiently than carbon dioxide.
Researchers are examining a variety of tactics, including breeding or genetically engineering cows that belch less, or adjusting the bacterial mix in cows’ stomachs. But altering the cows’ feed has shown the most promise thus far. Since January, cows at 15 farms across Vermont have had their grain feed adjusted to include more plants like alfalfa and flaxseed — substances that, unlike corn or soy, mimic the spring grasses that the animals evolved long ago to eat. As of the last reading in mid-May, the methane output of [one test] herd had dropped 18 percent. Meanwhile, milk production has held its own [The New York Times].
A $53 million effort drawing on the work of over 300 researchers has, after six years, produced something of great value to evolutionary biologists and farmers alike: the complete cow genome, which researchers say holds clues to the cow’s evolutionary history, as well as instructions on how to breed better cattle for milk and meat production. One research group sequenced the complete genome of a female Hereford cow, and researchers say that hidden in her roughly 22,000 genes are hints of how natural selection sculpted the bovine body and personality over the past 60 million years, and how man greatly enhanced the job over the past 10,000 [Washington Post]. Another spinoff research project studied the genetic variants between different breeds, and revealed some of the genetic keys to high-quality milk and beef.
Traits carried by bulls are important in determining how much milk a cow produces. Because bulls don’t make milk, however, a bull’s “performance profile” has to be sketched by observing the milk production of his daughters — a process that takes about six years and costs $25,000 to $50,000. Now, male calves can be tested at birth for milk-enhancing traits using gene-chip technology [Washington Post]. Early versions of these gene chips are already in use, ranchers say, but the new information may allow a new level of precision. Researchers also suggested that the genetic information could be used to breed cows that burp up less methane, a greenhouse gas that contributes to global warming.
Cattle and deer grazing in fields tend to align themselves with the Earth’s magnetic field, suggesting that the animals may have a built-in magnetic compass. A new study shows that animals in these herds tend to face towards either magnetic north or south, which has come as a surprise even to those who spend their days with bovines. Asked whether he had ever observed such behavior in cows, dairy farmer Rob Fletcher of Tulare, Calif., said, “Absolutely not.” But, he added, “I don’t spend a lot of time worrying about stuff like that” [Los Angeles Times].
Researchers used satellite imagery from Google Earth to look for patterns in more than 300 cow-filled pastures from every continent except Antarctica, and in more than 250 herds of deer in the Czech Republic. While every individual animal didn’t face the same direction, the herds, on average, pointed towards either magnetic north or south. That orientation didn’t consistently line up with any aspect of the terrain on which they were grazing, the direction from which the wind was blowing or the direction from which the sun was shining, [co-author Hynek] Burda says. In fact, many of these field observations were made at night, he notes [Science News].