New research weighs environmental pros and cons of livestock grazing

March 22, 2018

As our world grows a little more crowded by the minute, cattle producers are faced with new pressures regarding sustainability and environmentally friendly practices. The beef industry especially is looking for ways to produce more protein with less land, and with fewer damaging effects on the environment. Now, new research examines how different livestock feeding methods have different impacts on the air and land nearby.

The study, written by researchers at Michigan State University (MSU) doesn’t disregard areas where the industry isn’t sustainable, but it raises new points about the environmental impact of grazing and carbon emissions. Specifically, researchers examined three ways cattle are fed: adaptive multi-paddock (AMP) grazing, grass-fed operations and grain-fed feedlots.

AMP grazing involves having a large amount of livestock graze for short periods of time in small areas, with long breaks between grazing periods. As the livestock are moved from area to area, other grazing lands have time to recuperate. This allows plants to grow back with stronger root systems, which in turn leads to healthier soil that better absorbs moisture.

“Globally, beef production can be taxing on the environment, leading to high greenhouse gas emissions and land degradation,” said study leader, MSU professor of animal science Jason Rowntree. “Our four-year study suggests that AMP grazing can potentially offset greenhouse gas emissions.”

MSU collected data from previous studies, from its own feedlot herds, and from its grazing fields (which saw about 200 cattle in 600 acres of grass). The researchers documented carcass weight, daily weight gain and other figures from the cattle finishing phase and compared these numbers to greenhouse gasses from the animals’ digestion, manure storage, feed production and energy use on the farm.

In the end, feedlots were connected with greater amounts of nitrogen emissions of the fertilizers used to produce feed. On the other hand, feedlots produced the same amount of beef using half the land. On a grand scale, mass use of feedlots would leave land for other uses — like growing food — and mass use of AMP grazing might result in fewer greenhouse gasses.

“AMP is not as productive as feedlots, based on yields, but the AMP grazing system produced considerably greater amounts of beef on a land basis as compared to continuous grazing, showing that improved management can increase the output of grass-fed beef,” Rowntree said.

"We're not advocating for one approach over another, but rather we looked at different cattle production methods, and we see best practices and areas of improvement that support environmental stewardship in grass- and grain-fed systems," he said.