Feeding 2 billion more people in 35 years while reducing the resources we use today to produce food! That is the fundamental challenge of sustainability. Throughout history, humankind’s habit has been to use up local resources as the population grew and move on when the local resources were depleted. That option is no longer available. Nearly all arable land is already cultivated and that available land mass is quickly shrinking due to urbanization, erosion, and other factors.
Reducing food waste and reducing over indulgence by many and changing eating habits by some are certainly solutions; however these efforts are not sufficient by themselves to meet the challenge. The fact is we will still need more food produced. For meat, milk, and eggs, there are only two ways to do this; increase animal productivity or increase the number of animals. Increasing animal numbers will only increase the resource demands of animal source protein production. Thus increasing productive efficiency (input/output) is a necessity. This is possible but we must use the appropriate evaluation systems to measure progress.
Current evaluation methods of progress were primarily developed for assessing energy and resource use of machines and buildings. While the laws of physics apply equally to the engineering world and biology, living beings are not machines. Machines can be redesigned to use energy more efficiently; alternatives to carbon based fossil fuels can be used and we can turn machines off when not in use and back on again. It is not true of these options with living beings. Living organisms are hard-wired to survive on carbon based food. Survival, known as maintenance is an obligatory function meaning it is a need met above all other bodily functions. What other functions? The non-obligatory functions that do not contribute to day to day survival of an individual are growth, lactation, and reproduction. These non-obligatory functions are the source meat, milk, and eggs respectively. Thus before there is any productivity, we need to provide feed for survival first. Only after maintenance feed is provided do we get meat, milk and eggs. Using an economic term, maintenance feed is a fixed cost to food production. Given this, another economic principle applies; the only way to reduce fixed cost per unit of production is to spread that fixed cost over more units of production (increase productivity).
For example, a dairy cow producing 15 liters of milk needs 15 kg of feed daily. If that same cow was producing 30 liters daily she would need 21 kg of feed. If we had needed 30 liters of milk, we save 9 kg/d of feed (21 kg instead off 30 kg) by having 1 cow producing the 30 liters instead of two cows producing 15 liters each. This savings is called dilution of maintenance because we need to maintain fewer cows to get the same amount of milk. This principle applies across all animal protein production. For egg production, the analysis is the same. For meat production the primary driver to determine how much feed is for maintenance we count the number of days from birth to market.
The bottom line: we must protect animal health and wellbeing and we can reduce food waste and change eating habits. However these are not sufficient to meet the growing demand. We also cannot afford environmentally to continue to add animals to our production systems. We must, in addition to everything else, increase production efficiency. That is how we can increase food supply and reduce the environmental impact of food production simultaneously and we must!
Roger Cady currently serves as Global Sustainability Lead for Elanco working across animal protein species to provide information to the retail chain in support of sustainable agricultural practices. He is currently focused on methods to reduce natural resouce use in the production of animal protein and promote environmentally sound and economically viable practices in the food animal production.