Download PDF


    The ability to preserve meeting the needs of future generations while adequately serving the present population (sustainability) requires the control of greenhouse gas (GHG) emission and the prevention of damage to air, water, and soil. Simultaneously, growing populations and rising purchasing power in developing countries will strain the earth’s finite capacity to produce sufficient high-quality protein and nutritionally rich foods, which demands efficient food production. Fortunately, a growing body of evidence related to food production from animal origin suggests that production efficiency leads to environmental stewardship.

    The current situation is as follows:

    • The United Nations (UN) estimates the current world population at 7.7 billion and projects an increase to 9.7 billion by 2050. The population growth rate in sub-Saharan Africa is projected to double by 2050.1
    • Food security will continue to be a major challenge. The UN’s Food and Agriculture Organization (FAO) estimates that the number of undernourished people, which has been on the rise since 2015, will revert to 2010/2011 levels, at about 822 million, in 2018.2
    • These rapidly increasing populations are accompanied by increased income along with increased demand for meat and other animal products. Global demand for meat and milk is expected to rise through 2050, with demand for animal-derived products increasing 70% and the greatest increase expected to come from poultry products.3
    • Properly managed modern animal production systems and technologies have clear environmental advantages over older, less-efficient production models. To produce the same amounts of milk, modern dairy production requires 79% fewer animals, 77% less feed, 65% less water, and 90% less land than 1944 systems. Modern dairy systems produce 76% less manure and 63% less carbon than 1940 operations.4 Modern beef production requires 30% fewer animals to produce 11.9 billion kilograms of meat while producing 19% less manure and 16% less carbon compared with 1977 practices that produced 10.5 billion kilograms of meat.5
    • Furthermore, continuous improvements in production practices have consistently increased milk production efficiency: US milk production per cow increased 14% in 2017 compared with 2007.6
    • The US Environmental Protection Agency estimates that GHG emissions contributed by the total agricultural sector stands at 10%,7 of which less than 4% is from livestock,8 in contrast to global estimates of 14.5% contributed by the livestock sector. This difference is accounted for mainly by land use and changes that resulted in reduced agriculture sector GHG emissions.7
    • The FAO concludes that livestock production intensification offers significant opportunities to mitigate climate change, largely by increasing feed efficiency and thereby reducing the need to expand feed production on environmentally sensitive land. The FAO estimates that, by partially reducing the “emission intensity gap” between livestock operations that generate high emissions versus those that generate low emissions per unit of product, emissions could be cut by about 30%.9

    Policy Statement:

    FASS supports minimization of greenhouse gas emission and proper management of manure nutrients to avoid environmental damage from the necessary production of food of animal origin.

    Policy Objectives:

    • FASS opposes restriction on animal production technologies when these restrictions may reduce efficiency and increase environmental degradation.
    • FASS supports increased research, extension, and education funding directed to improving environmental quality by increasing feed efficiency by animals.

    Reviewed and revised by the FASS Science Policy Committee on February 23, 2021

    Adopted by the FASS Board of Directors on November 16, 2021

    For more information, please contact

    1 United Nations. Growing at a slower pace, world population is expected to reach 9.7 billion in 2050 and could peak at nearly 11 billion around 2100.

    2 FAO (Food and Agriculture Organization of the United Nations). 2019. The state of food security and nutrition in the world 2019: Safeguarding against economic slowdowns and downturns.

    3 Mottet, A, and G. Tempio. 2017. Global poultry production: Current state and future outlook and challenges. Worlds Poult. Sci. J. 73:245–256.

    4 Capper, JL, RA Cady, and DE Bauman. 2009. The environmental impact of dairy production: 1944 compared with 2007. J. Anim. Sci. 87:2160-2167.

    5 Capper, JL. 2011. The environmental impact of beef production in the United States: 1977 compared with 2007. J. Anim. Sci. 89:4249–4261.

    6 Capper, JL, and RA Cady. 2020. The effects of improved performance in the U.S. dairy cattle industry on environmental impacts between 2007 and 2017. J. Anim. Sci. 98:1–14.

    7 US Environmental Protection Agency. Sources of greenhouse gas emissions.

    8 US Environmental Protection Agency. Greenhouse gas inventory data explorer.

    9 FAO (Food and Agriculture Organization of the United Nations). Greenhouse gas emissions: Key facts and findings.