Whether or not you believe in human-perpetrated global climate change, there is increasing recognition that you — bovine veterinarians — are helping fight it. How so? By improving the production efficiency of your clients’ herds.
We’ve seen extensive coverage in the consumer media lately regarding greenhouse-gas (GHG) emissions and the role of livestock, specifically cattle, in producing them. The EPA, for example, recently released its 1990-2012 Greenhouse Gas Emissions Inventory, outlining its estimates for emissions of various GHGs and their sources. By far, the largest volume of GHG in the United States is carbon dioxide (CO2), accounting for approximately 82.5 percent of the total, with most coming from electricity generation, transportation and industry. Methane emissions, which the report says are down nearly 11 percent since 1990, are the second-largest contributor at 9 percent of the total.
Methane, however, is considered to have 25 times the global-warming potential as CO2, and it is the primary GHG attributed to cattle. The EPA report attributes 25 percent of U.S. methane emissions to enteric fermentation. The report says beef and dairy cattle are the largest methane emitters, and from 1990 to 2012, total methane emissions from enteric fermentation have increased 2.3 percent.
Now for the good news: While beef cattle emissions increased just 0.6 percent from 1990 to 2012, the cattle population dropped 5 percent and production increased 14 percent. Likewise, dairy emissions increased 6 percent while the population declined 2 percent and milk production increased 36 percent. EPA says this indicates emissions per unit of product are decreasing.
That fact, however, often is lost on the media, the public and our politicians. In March, the White House launched a strategy to cut methane emissions as part of its Climate Action Plan. Most of the media reports regarding the plan speculate on how to reduce methane emissions from each cow, through genetics, special rations or even cow backpack systems for capturing methane. While there might be opportunities to reduce emissions per cow, the coverage misses the benefits of production efficiency.
At a recent conference, Frank Mitloehner, PhD, an air-quality specialist from the University of California- Davis, recalled the infamous 2006 “Livestock’s Long Shadow” report from the UN’s Food and Agricultural Organization (FAO). That’s the one that claimed livestock account for 18 percent of global GHG emissions — more than the global transportation sector. Mitloehner evaluated that study and found glaring errors. Specifically, the authors conducted a full “life cycle analysis” in estimating livestock emissions, including all inputs such as land use change, fertilizer manufacturing, grain production and more. For the transportation sector, they limited their analysis to tail-pipe emissions
Mitloehner pointed out these inconsistencies and the FAO admitted the error, and in fact, recruited him to head up a task force currently developing uniform, global standards for measuring livestock GHGs.
Currently, most of the increase in global GHG emissions takes place in the developing world, Mitloehner says. U.S. dairies, for example, average over 20,000 pounds of milk per cow per year. Dairies in Mexico average 4,000 pounds, and in India 1,000. So it takes five Mexican cows or 20 Indian cows to equal the production of one U.S. cow. Your efforts to improve productivity set the standard for sustainable milk and meat production.