ry for efficient digestion (Global Livestock Group). Of the annual global
             production of 400 to 600 million tons of methane, ruminant livestock produce about 80 millions tons, or 22
             percent. An adult cow may emit only eighty to 120 kilograms of methane, but with about 100 million cattle in the
             United States and twelve billion large ruminants worldwide, it is easy to see why ruminants are one of the largest
             methane sources (Environmental Protection Agency). Besides the methane production of the digestive process, the
             stagnant waste lagoons of factory-farm operations emit an additional 5 percent of human-induced methane
             In addition to methane, animal agriculture also leads to the emission of other greenhouse gases into the
             air. The production of feed and heating of livestock housing uses fossil fuels which emit carbon dioxide, and the
             growing of livestock feed requires intense use of synthetic fertilizer, releasing nitrous oxide. These gases, along
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