Livestock farming in the U.S. releases a lot of greenhouse gases, mainly methane and nitrous oxide. Beef cattle produce the most methane, followed by dairy cows and pigs. Anaerobic lagoons are a big source of emissions from dairy cows, while deep pits are a major source for pigs. One way to reduce methane emissions is by covering lagoons and using the gas. Lowering the nitrogen in manure through diet changes can also cut nitrous oxide emissions.