Page 44 - The Welfare of Cattle

ChaPter 3

Dairy and Beef Sustainability: Nutrient
Loss and Use efficiency

Joe Harrison
Washington State University
Alan Rotz
USDA—Agricultural Research Service

CONteNtS

Sustainability Defined ...................................................................................................................... 21
Extensive vs Intensive Systems........................................................................................................22
Efficiency of Production ..................................................................................................................24
Improving Sustainability ..................................................................................................................25
References ........................................................................................................................................25

SUStaINaBILItY DeFINeD

Sustainability likely has as many definitions as individuals who wish to define it, and the
definition is normally biased toward the perception or goal of the one defining. A general defini-
tion is normally stated something like “Meeting the needs of the present without compromising
the ability of future generations to meet their needs.” Developing a more specific definition and
quantifying sustainability becomes difficult. Sustainability is generally viewed to consist of three
major categories of issues: environmental, economic, and social. Each of these major areas consists
of many smaller categories (Figure 3.1). For example, environmental issues include air quality,
water quality, water use, energy use, resources use, etc. Within the category of water quality, there
are pollution issues related to nutrient losses, pathogens, toxic compounds, hormone levels, etc.
Quantifying these individual environmental impacts is possible, but often requires much effort.
Quantifying social issues such as animal welfare is even more difficult, often relying on qualitative
measures.
Life cycle assessment (LCA) has become a common tool used to evaluate and quantify
sustainability. This accounting tool is used to integrate all impacts over a full life cycle and express
them per unit of product or service received. For dairy, the intensity of the impact or footprint is
normally expressed per unit of fat and protein corrected milk consumed. For beef, it is the unit of
meat consumed. Greenhouse gas emission intensity or carbon footprint has received much attention
as a measure of the sustainability of beef and dairy cattle products (Steinfeld et al., 2006), but a true
assessment of sustainability must be much more comprehensive. Greenhouse gas emissions are only

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