Got Weeds? Breed Sheep!
|Rambouillet sheep prefer mountain big sagebrush over many other types of rangeland plants, ARS researchers have found. And it's not just in their taste buds—it's in their genes.
"Other scientists have found genetic influences on diet preference in mice, goats, cattle, and people," says ARS geneticist Gary D. Snowder. "Now we've found that heredity also plays a role in the sheep's preference for sagebrush."Snowder works at ARS' U.S. Sheep Experiment Station in Dubois, Idaho.
The genetic findings may eventually give producers another tool for better using rangeland forage.
"If we can breed sheep to favor specific plants, we could help both the animals and the environment," Snowder says. For example, breeding animals so that they prefer an especially nutritious feed could enhance production. Or the sheep could be bred to prefer invasive weeds. They already eat some, like leafy spurge.
Snowder and colleagues from the University of Idaho, Texas A&M University in San Angelo, and the ARS Meat Animal Research Center in Lincoln, Nebraska, analyzed the foraging preferences of sheep from September to October in 1996 and 1997. Their discovery of a sagebrush preference could benefit land managers.
"Sagebrush is a common plant, covering at least 100 million acres of western rangeland. Although it is a native plant, it is viewed in some areas as invasive and undesirable," he says.
Snowder says it's likely that other dietary preferences of sheep also have a genetic component. If sheep can be used more extensively to control exotic weeds, they could help reduce the takeover of native habitat. The U.S. Department of the Interior estimates that invasive plants and weeds spread over federal lands at a rate of 4,600 acres per day.—By Kathryn Barry Stelljes, Agricultural Research Service Information Staff.
Gary D. Snowder is at the USDA-ARS U.S. Sheep Experiment Station, HC 62, Box 2010, Dubois, ID 83423; phone (208) 374-5306, fax (208) 374-5582.
"Got Weeds? Breed Sheep! " was published in the December 2000 issue of Agricultural Research magazine.