Sustainable awakening

Livestock farming plays a role in the production of greenhouse gases, but are ruminants key to solving this global problem?

Added value

In contrast to voices claiming that ruminants are using land that could be used for food production for human consumption, cattle are delivering high-nutritional protein. Consider this: for every 0.12 kg of food intended for us but consumed by ruminants, they produce 0.45 kg of animal products.

Furthermore, for every 45 kg of plant-based food produced for humans, 16 kg of byproducts are generated. These can be fed to ruminants, thus reducing the amount of byproducts destined for decomposition.

More practically, ruminants largely consume feed that is unsuitable for our consumption and occupy uncultivable land. At the same time, they consume lower-quality protein sources to produce extremely high-protein foods—milk and meat. These and many other topics were the focus of the Net Zero Carbon conference, held at MVP Dairy (Celina, Ohio, USA) last November.

Greenhouse gases

Milk production results in the release of greenhouse gases such as methane, nitrous oxide, and carbon dioxide. Some of the main sources of greenhouse gas emissions on dairy farms are feed production, fermentation, and waste production.

Although estimates differ regarding the contribution of greenhouse gas emissions from dairy herds, the best report that evaluates entire systems indicates that livestock contributes approximately 4% of greenhouse gases, of which milk contributes 1.9% of total national emissions in the US.

The theoretical maximum greenhouse gas reduction in dairy production systems is approximately 56%, primarily from reductions in methane released by waste. However, to fully achieve carbon neutrality, we would need to turn food production into a carbon "sink," thus offsetting methane production. Using electricity generated by renewable natural gas, replacing fossil fuels, could also contribute to carbon neutrality in the dairy industry.

10-year horizon

The change in methane concentration in the atmosphere is what impacts climate warming potential. If we can reduce the concentration of methane in this gaseous layer surrounding our planet, the warming potential will be reduced.

This is possible because methane, unlike carbon dioxide, degrades relatively quickly in the atmosphere—approximately 10 years. As the dairy chain has improved efficiency, with fewer cows needed to produce more milk, methane production per unit of milk produced has decreased. However, the concentration of animals and waste on farms, as well as increased feed consumption, has resulted in higher methane production per cow.

Since we are unable to prevent cows from producing methane through ruminal fermentation, our strategies focus on manure management—recognized as the sector with the greatest potential for transformation—and the way we produce feed for our herds. Furthermore, there are likely opportunities for the genetics sector to reduce methane production in cattle, although this mechanism is part of ruminant physiology and cannot be completely eliminated.

Sustainability in action

Representatives from MVP Dairy and Danone discussed their commitment to regenerative agriculture and how they are evaluating their current practices and strategies to improve sustainability. Regenerative agriculture was defined as the protection of soil, water, and biodiversity, in addition to a commitment to animal welfare.

Danone currently has over 56,000 hectares enrolled in a soil health program. One of the strategies used on the farms is to grow cover crops to increase carbon sequestration, resulting in an estimated 3% to 5% reduction in net carbon dioxide (CO2) equivalents.

The organization is using a third-party program to collect sustainability data and estimate the farms' carbon footprint. Danone works in partnership with dairy farms to develop a plan for continuous and sustainable improvement, including feed production and waste management.

SINCE WE ARE UNABLE TO PREVENT COWS FROM PRODUCING METHANE FROM RUMINAL FERMENTATION, OUR STRATEGIES FOCUS ON MANAGEMENT OF WASTE AND PRODUCTION OF FEED FOR THE HERD

With a focus on waste management, Dairy Management Inc. has initiated strategies to achieve the initiative's goal of becoming carbon neutral by 2050. The pilot project plans to adopt technologies and optimize practices on up to five dairy farms, transforming them into living laboratories for sustainability.

The objective of the proposal is to understand the collective impact of implementing practices and to widely disseminate information to the sector.

Examples of technologies evaluated for reducing greenhouse gases include waste management systems: dissolved air flotation, nitrification/denitrification, and evaporative systems, which are recognized for their greatest contribution to reducing these pollutants.

Evaluating goals

As agriculture and the dairy industry develop environmental sustainability goals, it's important to understand where improvements are likely to be made and how to evaluate established targets. While most of the greenhouse gas emitted by dairy cattle is carbon dioxide, its exchange with soil and plants negates its primary focus.

Therefore, methane produced by ruminal fermentation and the storage and use of manure should be the main focus in assessing targets and reducing carbon dioxide equivalents .

REGENERATIVE AGRICULTURE HAS BEEN DEFINED AS THE PROTECTION OF SOIL, WATER AND BIODIVERSITY, IN ADDITION TO A COMMITMENT TO ANIMAL WELFARE

Measuring Success

Researchers at Ohio State University have developed tools to measure greenhouse gas emissions from soil and animals, with a particular focus on methane. Methane emissions can be assessed in animals in feedlots or managed in pasture systems. Because carbon sequestration on dairy farms remains a concern, farm-specific estimates will be much more meaningful than regional or generalized results.

Improving the accuracy of greenhouse gas emissions estimates will be important for dairy farms to effectively assess whether they are meeting their sustainability goals.

One question raised during the debate was: “Do you honestly think people care about sustainability?” Each speaker revealed a different perspective when answering the question.

According to those involved in the debate, young people want to understand how agricultural activity is helping or hindering sustainability efforts. Furthermore, it was pointed out that investors are concerned about achieving sustainability goals, and as a result, companies are implementing action plans to reduce carbon emissions.

The speakers indicated that there are solutions that may not be available now, but can be developed with a focus and funding on sustainability. More importantly, it became clear that the industry will continue to be questioned whether it is the problem or the solution when it comes to environmental sustainability.

APRIL 2022, VOLUME: 167, NO. 5

ORIGINAL PUBLICATION: “WILL DAIRY BE A SOLUTION FOR GREENHOUSE GASES?”

APRIL 2022 ISSUE OF HOARD'S DAIRYMAN.

AUTHORIZED REPUBLISHMENT OF THE APRIL 2022 ISSUE OF HOARD'S DAIRYMAN.

COPYRIGHTS 2022 BY WD HOARD & SONS COMPANY, FORT ATKINSON, WISCONSIN.

ADOPTION: WHOLE MILK MAGAZINE TEAM.

JACKIE BOERMAN

EMILY LUC

MAURICE EASTRIDGE

BARRY BRADFORD

The authors are animal scientists at Purdue University, Purdue Extension, Ohio State University , and Michigan State University , respectively.