Alternative Systems and the Environment

Livestock and poultry producers are increasingly adopting more and more
of what are perceived as welfare-friendly practices. Forces behind
changes include improved education about production practices and
animal well-being

Livestock and poultry producers are increasingly adopting more and more of what are perceived as welfare-friendly practices. Forces behind changes include improved education about production practices and animal well-being, retailer and consumer demands, and activist pressure through mechanisms such as ballot initiatives. Often consumers may inherently associate livestock-intensive systems with environmental degradation while considering non-confined systems, such as those often promoted as animal-friendly, better for the environment.

Ammonia Check The environmental consequences of mandated production practices may not be adequately considered, nor studied. Advertisement

While efforts to improve animal well-being are well-intended, the consequences of mandated production practices may not be adequately considered nor studied. Systems designed to promote good animal welfare do not always promote good environmental health and vice versa.¹

Ammonia emission
Researchers have suggested that the most common outdoor systems used for intensive organic production of pigs and poultry have significant environmental impacts, including increased risk of nitrogen-leaching and ammonia volatilization, as well as negative consequences for animal welfare, such as nose-ringing of pigs.^1,2 Increased ammonia emissions occur, in part, because of the contact of excreta with the natural environment (solar radiation, wind). Similarly, increasing the available space per animal increases surface area per mass of excreta, which also leads to increased emissions, again because there is greater opportunity for wind and solar effects to contribute to volatilization.³

If one considers a cage-free system where birds can spread their wings without making contact with either the side of an enclosure or another bird, the increase in amount of space provided to each bird likely corresponds to an increase in emissions. Floor systems that allow for ‘dust bathing’ behaviour, likely enhance nitrogen volatilization as well. At present there are little data to demonstrate how production practices, adopted for the purpose of improving animal well-being, alter the environmental impact ammonia emissions. However, with increasing concern over air emissions resulting from the production of livestock and poultry, the need for such research is great.

Nutrient inputs/outputs
Combined welfare-friendly and organic systems may require greater nutrient inputs to reach the same production endpoint. Researchers have demonstrated that while egg production increased with increasing cage space, feed intake increased as well.⁴ The overall result may be less efficient nutrient utilization.

In cases where the production environment requires greater nutrient inputs to meet nutrient maintenance and production requirements a greater mass of unabsorbed nutrients can be lost to the environment through excreta followed by the potential for more nutrients (total mass) to be volatilize to the air and/or runoff/leach into water resources.

Nutrient distribution is already a concern on the national scale. Outdoor production systems contribute to nutrient distribution concerns at a farm scale. Containment of nutrients to prevent entry to surface and ground waters is of paramount importance when animals are reared outdoors. However, consideration of containment is often overlooked and many states regulate confined production systems differently than outdoor production systems.

Resource utilization
When productivity (unit of output per unit of input) is reduced, more resources (energy, water, nutrients) are needed to meet the same level of output. In the case of space allocation, providing animals with more space will increase productivity, however, there may be a point at which any additional space translates to greater resource allocation without a return on the input.⁴ With a finite amount of earth, feeding an increasing population while simultaneously increasing space allocated per unit of food production will eventually lead to a situation of competing resources, likely resulting in environmental insult to the land resources or a prioritization of need for generated products (e.g., housing for an increasing population versus animal products in the diet).

Individual operations can vary in the amount of space allotted, providing opportunity for multiple production systems to co-exist. However, livestock and poultry producers, as a whole, can increase space allotment to only a finite extent.

It has been found that optimizing feed composition to incorporate highest yield feed crops and regional sources for feed will reduce land area requirements for pork, chicken and beef, but the authors acknowledge that the world’s optimal feed production regions are insufficient to meet the world’s meat demand when land use intensity is reduced.⁵

Therefore, the results suggest that moving toward an animal-friendly agriculture system of reduced confinement and more ‘natural’ diet while maintaining demand for animal products will require greater land resources than conventional animal systems.¹

It has already been noted that producing higher quality, high-yield feed crops to improve animal diets could reduce some air emissions and reduce overall land requirements needed by animal agriculture. However, these crops generally require greater inputs of fossil fuel-based fertilizer, pesticides, and irrigation water to achieve high yields.6 These upstream inputs of chemicals and energy will contribute negatively to the environmental, human-health, and ecological impacts of an animal-based production system.

Data are limited documenting the environmental impact of production systems designed to improve animal well-being. Too often research is conducted considering only a limited number of outcomes, without addressing or even identifying potential unintended consequences. However, as retailers and consumers continue to push livestock and poultry production to change common production systems, we need to recognize and address our current limited understanding about the environmental costs of ethical animal production.

Presented at the 2009 Midwest Poultry Federation Convention. Wendy Powers is a Professor/Director of Environmental Stewardship for Animal Agriculture, Michigan State University, e-mail: wpowers@msu.edu.  Janice Siegford is an assistant professor, Department of Animal Science, Michigan State University.

References
1. Siegford, J.M., W. Powers, H.G. Grimes-Casey. 2008. Environmental aspects of ethical animal production. Poult. Sci. 87:380-386.
2. Hermansen, J. E., K. Strudsholm, K. Horsted. 2004. Integration of organic animal production into land use with special reference to swine and poultry. Livest. Prod. Sci. 90:11-26.
3. Monteny, G. J., C.M. Groenestein, and M. A. Hilhorst. 2001. Interactions and coupling between emissions of methane and nitrous oxide from animal husbandry. Nutrient Cycling in Agroecosystems 60:123-132.
4. Jalal, M. A., S. E. Scheideler, and D. Marx. 2006. Effect of bird cage space and dietary metabolizable energy level on production parameters in laying hens. Poultry Sci. 85:306-311.
5. Elferink, E. V. and S. Nonhebel. 2007. Variation in land requirements for meat production. Cleaner Production 15:1778-1786.
6. Ward, G. M., K. G. Doxtader, W. C. Miller, and D. E. Johnson. 1993. Effects of intensification of agricultural practices on emission of greenhouse gases. Chemosphere 26:87-93.