Environmental Impact Of Animal Agriculture

Activists protesting against animal agriculture.
Activists protesting against animal agriculture.

Animal agriculture involves the production of livestock and animal by-products for human consumption. Huge tracts of land and millions of gallons of water are needed to grow, feed, and raise these animals. The environmental impact of this practice is detrimental to the land, air, and water and involves the unsustainable use of fossil fuels. It is one of the biggest contributors to global climate change and deforestation around the world, presenting a great threat to the world’s biodiversity.

Some of the facts are astounding. For example, animal agriculture is responsible for emitting 18% of all greenhouse gasses, and this is expected to increase 80% by the year 2050. The production of one calorie of animal protein requires ten times more fossil fuels than it takes to produce one calorie of plant protein. Factory farming is responsible for much more destruction including chemical fumes, toxic runoff, and unsustainable water use (to name a few). The animal waste that runs off these livestock lots pollutes local waterways with pesticides, herbicides, hormones, antibiotics, phosphate-rich fertilizer, and bacteria. This waste is reducing clean water availability around the world and reduces the availability of the uncontaminated fish supply. In addition, the massive amount of animals produced on small areas of land is unsustainable and leads to reduced soil fertility and desertification, a loss of plants and the inability to regrow lost flora.

Livestock and Its Waste Production

Various types of animals are raised to fulfill demands for meat and by-products like cheese and eggs. Typical livestock includes pigs, beef cows, dairy cows, poultry (like chickens and turkeys), goats, and sheep. The following information identifies the environmental impact and waste production of the US-based factory farming of each of these animals.

Dairy cows

Dairy cows are raised in the US for the production of milk, cheese, yogurt, and other dairy products. These cows produce approximately 120 pounds of waste per cow per day. In the US, farmers are raising around 9 million dairy cows, which means 1.08 billion pounds of waste daily. To put it into perspective, a farm with only 2,500 cows produces the same amount of waste as a city of around 400,000 people.


Cattle raised for meat produce less than lactating cows. However, there are 90 million of them in the US. This large number of animals combined with the 63 pounds of waste each one produces on a daily basis ends up at 5.67 billion pounds every day. In addition, these cows require more than 2,400 gallons of water and 16 pounds of grain for every pound of meat produced. With high global rates of hunger, malnutrition, and water scarcity, that level of resource inefficiency is hard to justify.


The pig population in the US is around 67 million and is also raised for meat consumption. Each pig produces, on average, 14 pounds of waste per day. Thus 938 million pounds of solid waste produced daily by pigs. While toxic fumes are a big problem for all livestock, ammonia is of particular concern on pig farms. Ammonia increases smog levels and causes respiratory illnesses like asthma and lung inflammation.

Sheep and Goat

Not commonly considered as having a big role in US livestock production, the sheep and goat population is as big as the population of dairy cows. These animals also produce massive amounts of waste. Each sheep and goat create 5 pounds of waste daily. When multiplied by the 9 million animals in the country, waste production equals 45 million pounds. This livestock is raised primarily for dairy products although there is some demand for their meat.


Last on the list is poultry which includes chickens, turkeys, geese, ducks, and the like for both egg and meat production. In the entire country, farms are raising around 9 million birds. Each bird produces roughly 0.25 to 1 pound of waste every day. These numbers represent up to 9 million pounds of waste daily. Nearly all, 98%, of poultry is raised on conventional farms that practice unsustainable production.

Combining all of these animals results in an astounding 7,742,000,000 (or 7.742 billion) pounds of waste - every single day. Additionally, 51% of US land (over 1.2 billion acres) is used for agricultural purposes including crops, grazing, and farms. Where does all of this animal waste go? It finds its way into human water sources, the air, and the ground. The gasses that are released in the air not only lead to pollution but also acid rain which destroys plant species and renders land infertile. Illegal discharge and unpreventable runoff contaminate public waterways, infecting humans as well as marine life. High levels of nitrogen in manure, when found in drinking water, can lead to birth defects. Both livestock and farm workers have died or been made sick due to high gas buildup from poor ventilation.

What Can Be Done?

Controlling and reducing the number of livestock produced in the US and around the world is vital in the fight against global climate change. Perhaps the biggest influence is in the hands of consumers. The single most effective change that consumers can make is to stop eating meat and when that is not possible, significantly reduce consumption. If people simply followed dietary guidelines, worldwide gas emissions from factory farming would reduce around 33% by the year 2050. Being a conscious purchaser also alleviates unsustainable agriculture practices. Whenever possible, buyers should support local businesses and purchase grass-fed animals. Not only would these dietary changes improve environmental health, but also personal health. Livestock consumption does more than attribute to environmental degradation. Overconsumption of meat is linked to diseases like diabetes, heart disease, high cholesterol, heart attacks, and some cancers. A reduced meat diet, or even vegetarian or vegan, would reduce the number of premature deaths and healthcare costs.

Change does not end with consumers, however. Policy amendments, and in some cases drastic overhauls, are also necessary. A reduction in government subsidies for concentrate feed combined with federal regulation to control hormone and antibiotic administration in factory farm animals would help mitigate greenhouse gas emissions as well. These changes could motivate production companies to graze livestock on grassland, reduce concentrate feed, and focus on disease prevention.

If nothing is done to curb this environmental destruction, humans, and the planet’s flora and fauna will suffer. Conventional farming is unsustainable and cannot continue at current rates if humans want to prevent the damaging effects of global climate change. Soon there will be nowhere for all of the waste to go as the earth is reaching its saturation point.

Waste Generated By Livestock In The United States: Adverse Environmental Impact

RankLivestockWaste ProductionApproximate Number of Livestock
1Dairy Cows120lbs of waste per day/per cow9 million cows
2Cattle 63lbs of waste per day/cattle species 90 million cattle
3Pigs14lbs of waste per day/per pig67 million pigs.
4Sheep/Goats 5lbs of waste per day/per sheep,goat9 million sheep/goats
5Poultry0.25-1lbs of waste per day /per poultry 9 billion birds

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