In recent years, climate change has become a topic of great concern as it is closely intertwined with human life and production. Similarly, the impact of climate change on animal husbandry in grasslands is also gradually emerging.


According to a report by the United Nations Food and Agriculture Organization, up to 18% of global human-caused greenhouse gas emissions come from livestock farming. This indicates the direct impact of livestock on global warming and the environmental impact of raising the world's estimated 63 billion farm animals.


Specifically, animal agriculture is responsible for:


9% of annual carbon dioxide (CO2) emissions are due to human activities.


37% of annual biogas emissions. Biogas has 20 times greater potential to contribute to climate warming than CO2.


65% of annual nitrous oxide emissions. Nitrous oxide has an additional potential to contribute to global warming nearly 300 times greater than carbon dioxide. Mapping of the Earth shows that the areas with excessive concentrations of nitrogen in the atmosphere also happen to be areas of intensive livestock farming.


At almost every stage of meat, egg, and milk production, climate change-accelerating gases are released into the atmosphere, thereby disrupting the climate, affecting temperatures, and compromising the balance of ecosystems. The United States has the highest methane emissions from livestock farming in the world, at 1.9 million tons.


As the livestock industry has become more intensive in recent decades, more livestock is concentrated on a few large farms. A significant proportion of livestock is kept in modern farming systems called factory farms, which resemble large warehouses, sometimes housing hundreds of thousands of animals.


As a result, livestock excrement accumulates in a small area around the farm. For example, in the United States, the Department of Agriculture estimates that U.S. farm animals excrete nearly half a billion tons of manure each year, four times the amount excreted by Americans. Worldwide, farm animals excrete billions of tons of manure each year.


Livestock feed is a high-concentration, high-protein diet derived from corn and soybeans. The production of this feed requires large amounts of fertilizer. Livestock farming is a major contributor to high fertilizer use. More than half of the corn grown globally is used for processing into feed. Corn requires more nitrogen fertilizer than any other crop.


Other feed crops, such as barley and sorghum, also require large amounts of nitrogen fertilizer. Overall, experts estimate that the fertilizers used in the cultivation of feed crops release "more than 40 million tons of carbon dioxide into the atmosphere each year."


Production patterns determine energy consumption. Large-scale confined factory farms, also known as "confined animal feeding systems" (CAFOs), consume substantial amounts of energy for lighting, heating, cooling, automating feeding and watering, and maintaining air circulation.


Moreover, the amount of coal and oil consumed to produce feed for livestock, agricultural machinery, seed selection, and the production of herbicides and pesticides often exceeds the amount of energy required for fertilizer production.


The coal and oil used on farms alone can release up to 90 million tons of carbon dioxide each year. However, farming methods that primarily rely on forage or crop residues for feed typically require minimal or no coal and oil.