Symposium review: Development of a funding program to support research on enteric methane mitigation from ruminants

Abstract

Enteric methane is a major source of greenhouse gas emissions from milk production systems. Two organizations based in the United States, the Foundation for Food and Agriculture Research and the Dairy Research Institute, have developed a collaborative program to align resources and fund projects to identify, develop, and validate new and existing mitigation options for enteric methane emissions from dairy and beef cattle. This collaborative program is called the Greener Cattle Initiative. The program will develop requests for proposals and award grants on projects that address challenges within, but not limited, to the following research areas: dairy and beef cattle nutrition, rumen microbiome, dairy and beef cattle genetics, sensing and data technology for enteric methane measurement and prediction, and socioeconomic analysis of enteric methane mitigation practices. The program is structured as a consortium with closed participation and a flat governance collaboration model. The Greener Cattle Initiative program will continue incorporating participants from the food and agriculture industry, commodity groups, and nonprofit organizations who share common objectives and contribute in-kind and matching funds to the program, up to a total of 10 organizations. Research findings will be communicated broadly, after a waiting period for exclusive access to program participants, to create shared knowledge on enteric methane mitigation. The Greener Cattle Initiative is expected to award up to $5 million in research grant funding in a 5-year period, which will contribute to advancing the voluntary greenhouse gas reduction goals established by both the United States and global dairy sectors.

Full text

ABSTRACT
Enteric methane is a major source of greenhouse gas
emissions from milk production systems. Two organiza-
tions based in the United States, the Foundation for
Food and Agriculture Research and the Dairy Research
Institute, have developed a collaborative program to
align resources and fund projects to identify, develop,
and validate new and existing mitigation options for
enteric methane emissions from dairy and beef cattle.
This collaborative program is called the Greener Cat-
tle Initiative. The program will develop requests for
proposals and award grants on projects that address
challenges within, but not limited, to the following
research areas: dairy and beef cattle nutrition, rumen
microbiome, dairy and beef cattle genetics, sensing
and data technology for enteric methane measurement
and prediction, and socioeconomic analysis of enteric
methane mitigation practices. The program is struc-
tured as a consortium with closed participation and
a flat governance collaboration model. The Greener
Cattle Initiative program will continue incorporating
participants from the food and agriculture industry,
commodity groups, and nonprofit organizations who
share common objectives and contribute in-kind and
matching funds to the program, up to a total of 10
organizations. Research findings will be communicated
broadly, after a waiting period for exclusive access to
program participants, to create shared knowledge on
enteric methane mitigation. The Greener Cattle Initia-
tive is expected to award up to $5 million in research
grant funding in a 5-year period, which will contribute
to advancing the voluntary greenhouse gas reduction
goals established by both the United States and global
dairy sectors.
Key words: dairy, enteric methane, funding
INTRODUCTION
Enteric methane is a major source of greenhouse gas
emissions from milk and beef production systems that
contribute to global warming. Enteric fermentation is
the second largest source of methane emissions after
natural gas and petroleum systems, and the second
largest source of agricultural greenhouse gas emissions
in the United States after nitrous oxide emissions from
managed soils (US EPA, 2021). Mitigation of enteric
methane emissions is a major focus of farmer-led vol-
untary efforts by the dairy sector in the United States
to meet environmental stewardship goals announced
publicly in the U.S. Dairy Stewardship Commitment
(Innovation Center for US Dairy, 2020). Similar goals
to accelerate climate change action and reduce green-
house gas emissions were announced recently by the
global dairy sector (Global Dairy Platform, 2021).
Mitigation of enteric methane from ruminants is
not a novel field of research. However, the number of
scientific publications in this area increased rapidly in
the last 2 decades due to the emphasis placed on the
effects of greenhouse gas emissions on climate change
(Beauchemin et al., 2020). Many articles reviewed the
scientific literature on enteric methane mitigation op-
tions (Hristov et al., 2013a; Knapp et al., 2014; Negussie
et al., 2017; Beauchemin et al., 2020; Lassen and Dif-
ford, 2020). Arndt et al. (2022) recently conducted a
meta-analysis to examine 98 enteric methane mitiga-
tion options from a comprehensive data set of treat-
ment means from 425 peer-reviewed studies published
between 1963 and 2018. They found that most of the
options (63 out of 98, or 64%) were not successful in
Symposium review: Development of a funding program to support
research on enteric methane mitigation from ruminants*
J. M. Tricarico,1† Y. de Haas,2 A. N. Hristov,3 E. Kebreab,4 T. Kurt,5 F. Mitloehner,4 and D. Pitta6
1Innovation Center for US Dairy, Rosemont, IL 60018
2Animal Breeding and Genomics, Wageningen University & Research, 6700 AH Wageningen, the Netherlands
3Department of Animal Science, The Pennsylvania State University, University Park 16802
4Department of Animal Science, University of California, Davis 95616
5Foundation for Food and Agriculture Research, Washington DC 20004
6Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Kennett Square 19348
J. Dairy Sci. 105
https://doi.org/10.3168/jds.2021-21397
© 2022, The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®.
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Received October 8, 2021.
Accepted March 30, 2022.
*Presented as part of the Production, Management and the
Environment Fall Webinar: Advances in Enteric Methane Mitigation
in Dairy Cattle—The Last Decade and Future Prospects at the ADSA
Annual Meeting Webinar Series, September 2021.
†Corresponding author: Juan.Tricarico@ dairy .org

Journal of Dairy Science Vol. 105 No. Sym, 2022
mitigating enteric methane. These authors also found
that only 5 options reduced enteric methane production
(g/d) and emissions intensity (g/kg of ECM or ADG)
without negatively affecting milk production (ECM),
and only 3 options reduced emissions intensity while
increasing animal productivity (ADG). This suggests
that many challenges remain in identifying, develop-
ing, and validating effective enteric methane mitigation
options that result in net emissions reductions for milk
and beef production that will also meet farmers’ and
broad socioeconomic needs.
Detailed discussion of enteric methane mitigation op-
tions is beyond the scope of this article. The contents
of this article were presented at the ADSA symposium
titled “Production, Management and the Environment
Fall Webinar: Advances in Enteric Methane Mitiga-
tion in Dairy Cattle—The Last Decade and Future
Prospects.” Its objectives are to review and synthesize
research challenges presented at the symposium and de-
scribe a program developed to address these challenges
by funding enteric methane mitigation research, called
the Greener Cattle Initiative (https: / / foundationfar
.org/ consortia/ greener -cattle -initiative/ ; last accessed
on Feb. 25, 2022).
ENTERIC METHANE AND OPPORTUNITIES
TO ADDRESS CLIMATE CHANGE
Unlike other sources of greenhouse gas emissions,
such as those from fossil fuel extraction and distribu-
tion that only contribute to atmospheric greenhouse
gases, milk production systems are part of the biologi-
cal carbon cycle and can function as a sink for green-
house gases, thereby contributing to reverting climate
change (Le Quéré et al., 2018). During the sympo-
sium, F. Mitloehner (University of California, Davis)
emphasized that methane has a substantially shorter
atmospheric lifetime than carbon dioxide and nitrous
oxide. Because emitted methane is continuously re-
moved from the atmosphere by hydroxyl oxidation,
its atmospheric warming effects depend on the rate of
emissions increase or decrease over the last 20 years
rather than the total cumulative amount emitted over
that period (Allen et al., 2018). The consequence of
this behavior is that mitigation of enteric methane
production at rates greater than its natural rate of
oxidation reduces atmospheric methane concentra-
tions, effectively reverting climate change effects
(Lynch et al., 2020). In other words, mitigating en-
teric methane production has an effect on atmospheric
warming similar to removing a fixed amount of carbon
dioxide from the atmosphere by sequestering it in soil
or plant matter (for example, by afforestation). Cain
et al. (2019) found that sustained annual reductions
of 0.3% in methane production are sufficient for at-
mospheric warming from methane to remain stable
over time. The implication is that mitigation of en-
teric methane production greater than 0.3% annually
that is sustained over time (i.e., year-over-year) could
be used to offset the atmospheric warming effects of
carbon dioxide and nitrous oxide emissions from milk
production systems. In this way, sustained mitigation
of enteric methane production becomes a valuable tool
for dairy value chains to meet their greenhouse gas
reduction goals. This opportunity to revert climate
change effects by focusing on mitigation of enteric
methane production places milk production systems
in a unique position to convert climate impact into
societal benefit.
GREENER CATTLE INITIATIVE TO FUND
ENTERIC METHANE RESEARCH
As presented by J. M. Tricarico (Innovation Center
for US Dairy) during the symposium, the Foundation
for Food and Agriculture Research (FFAR) and the
Dairy Research Institute (DRI) jointly developed the
Greener Cattle Initiative as a pre-competitive program
to support collaborative research on enteric methane
mitigation from ruminants. The FFAR is a 501(c)(3)
nonprofit organization, created by the US Congress to
complement the work of the United States Department
of Agriculture. The FFAR builds unique public-private
partnerships to support innovative science addressing
today’s food and agriculture challenges. The DRI is a
501(c)(3) nonprofit organization affiliated with the In-
novation Center for US Dairy, created to strengthen ac-
cess to and investment in the technical research required
to drive innovation and demand for dairy products and
ingredients domestically and abroad. Both FFAR and
DRI have agreed to identify additional organizations
from the food and agriculture industry, commodity
groups, and nonprofits that share similar scientific and
educational objectives for enteric methane mitigation
and are willing to contribute financially to the initia-
tive. The overall goal for the Greener Cattle Initiative
is to leverage resources through in-cash and in-kind
contributions to award multiple grants in response to
requests for proposals. The research objectives are to
identify, develop, and validate new and existing sci-
entifically sound, commercially feasible, and socially
responsible mitigation options for enteric methane
emissions from dairy and beef cattle (Figure 1). The
following critical areas for research were identified by
FFAR and DRI to develop requests for proposals under
the Greener Cattle Initiative:
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Journal of Dairy Science Vol. 105 No. Sym, 2022
• Dairy and beef cattle nutrition to incorporate com-
pounds fed in low quantities (equal to or less than
1% dietary DM) that directly or indirectly inhibit
enteric methane emissions without negative im-
pacts on animal performance, and feed ingredients
that alter ruminal metabolic pathways away from
methanogenesis when they are fed at quantities
that require diet reformulation,
• Rumen microbiome to understand how its compo-
sition and activity influences methane formation
and its inhibition,
• Sensing and data technology for enteric methane
measurement and prediction such as sensors, ro-
bots, artificial intelligence systems, and more,
to monitor enteric methane emissions or related
physiological indicators and markers and manage
individual animals to reduce emissions,
• Dairy and beef cattle genetics to develop selection
traits and programs that allow selective breeding
of low methane-emitting cattle, and
• Socioeconomic analysis of enteric methane mitiga-
tion options.
The development of effective enteric methane mitiga-
tion options that also meet economic and social re-
quirements for adoption requires research across these
various disciplines and possibly others. The following
section will briefly describe research needs and chal-
lenges specific to dairy cattle that are related to the
research areas listed, and were presented during the
symposium by A. N. Hristov (The Pennsylvania State
University), D. Pitta (University of Pennsylvania),
E. Kebreab (University of California, Davis), F. Mit-
loehner (University of California, Davis), Y. de Haas
Tricarico et al.: PRODUCTION, MANAGEMENT AND THE ENVIRONMENT
Figure 1. Areas of focus and expected impacts for research funds awarded by the Greener Cattle Initiative to identify, develop, evaluate, and
validate enteric methane mitigation options for beef and dairy cattle.

Journal of Dairy Science Vol. 105 No. Sym, 2022
(Wageningen University & Research), and J. M. Tri-
carico (Innovation Center for US Dairy).
RESEARCH NEEDS AND CHALLENGES
FOR ENTERIC METHANE MITIGATION
IN DAIRY CATTLE
Dairy Cattle Nutrition
Research on nutrition- and management-based enteric
methane mitigation options must continue and expand
to support identification and adoption of mitigation
options and better understand their consequences on
animal health, well-being, productivity, and product
quality. Better delivery mechanisms are needed for nu-
tritionally based mitigation options, especially under
grazing conditions (Beauchemin et al., 2020). Long-
term experiments are needed to examine the effects of
mitigation options on animal health, well-being, and
reproduction over a full lactation and multiple lacta-
tions. Long-term experiments are also needed to study
adaptation by the ruminal microbiome and the animal
to mitigation options. Appropriate experiments will
also be valuable to examine the long-term effects of
prolonged inhibition of methanogens or alteration of
ruminal fermentation pathways. It is also important to
understand the impacts nutritional mitigation options
can have on milk composition, shelf life, sensory at-
tributes, and consumer perception of dairy foods and
how they are produced. Finally, research exploring the
effects on dairy cow manure composition and manure
and soil emissions resulting from mitigation options
based on nutrition and feeding management, inhibition
of methanogens, or alteration of fermentation pathways
is also critically important.
Rumen Microbiome
Enteric methane is formed exclusively by metha-
nogens that use fermentation end products, such as
carbon dioxide and hydrogen, and keep the rumen in
a reduced state, allowing microbial feed digestion to
continue. Therefore, understanding how the ruminal
microbiome affects enteric methane emissions by dairy
cattle is another focus area for research that could
deliver both short- and long-term benefits. Knowledge
gaps in this area include improved understanding of
the relationships between fungi, bacteria, protozoa, and
archaea (i.e., methanogens) and how these interactions
affect methanogenesis, microbe-animal (host) interac-
tions, ruminal biochemical transactions including their
thermodynamic regulation, and how the microbiome
is influenced by the host, dietary reformulation, and
feeding practices. Information on the production rates
of volatile and branched-chain fatty acids resulting
from ruminal fermentation is also warranted. Explor-
ing methanogenic diversity and how their relative
contributions to methanogenesis vary by breed and
with fluctuating levels of forage and concentrate in the
diet is desirable. This type of research will help explain
differences in enteric methane emissions and the effec-
tiveness of mitigation options between confined feeding
and grazing systems. Also, determining the effect of
different mitigation options on individual methanogen
species (Pitta et al., 2021) and alternate hydrogen sinks
(Greening et al., 2019) would allow identification of
complementary options to further reduce methane for-
mation in the rumen. For example, this type of research
may help identify combinations of mitigation options
that are more effective based on the expected metha-
nogen diversity in animals under specific management
and environmental conditions. Finally, research explor-
ing the impact of applying interventions early in the life
of the animal on enteric methane production later in
life is also of interest (Meale et al., 2021).
Sensing and Data Technology for Enteric Methane
Measurement and Prediction
The importance of measuring and accurately predict-
ing both enteric methane emissions and the reductions
due to the adoption of mitigation options cannot be
overstated. Biophysical research to explore and develop
new sensing technology or new uses for existing sensing
technology is fundamental for accurate and robust en-
teric methane measurements and predictions (Negussie
et al., 2017). Easily measured physiological indicators
that can be used as robust estimates of enteric meth-
ane emissions and effects of mitigation options will be
critical to test and validate these options in sufficiently
large numbers of animals to provide confidence in the
response (Patra, 2016). The main challenge with indica-
tor variables is that accuracy is usually compromised,
and more accurate methods, such as using respiration
chambers, are laborious, slow, and expensive, thus
limiting the number of mitigation options and animals
that can be tested. The application of indirect indicator
methods in large numbers of animals will be valuable to
investigate the relationships between improving animal
health and enteric methane abatement that currently
have limited evidence (Hristov et al., 2013b). Data
collection, aggregation, and synthesis are also crucial
to increasing confidence in enteric methane mitigation
estimates. Increased confidence in mitigation estimates
is needed to develop socioeconomic innovation that en-
courages adoption of mitigation options. For example,
the development of robust and verifiable methodologies
to quantify enteric methane reductions is critical for
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Journal of Dairy Science Vol. 105 No. Sym, 2022
the creation of enteric methane mitigation-based cred-
its to be transacted in voluntary and compliance offset
markets (Allen et al., 2021).
Dairy Cow Genetics
Selectively breeding dairy cattle that naturally pro-
duce lower enteric methane emissions is an attractive
mitigation option that is cost-effective, permanent,
and cumulative (de Haas et al., 2021). This is possible
because enteric methane emissions are under a degree
of genetic control and are therefore heritable (de Haas
et al., 2021). Heritability estimates for methane emis-
sions in dairy cows range between 0.05 and 0.27, but
most estimates are >0.20 (Lassen and Difford, 2020).
Selection indexes that include multiple traits will need
to incorporate a methane emissions trait to ensure
that breeding programs are balanced. This is not an
easy task, as the methane emissions trait needs to be
defined, recordable, affordable, heritable, and represen-
tative of the phenotypic variation onto which selection
pressure is applied. In addition, its genetic correlations
with other traits within the breeding goal need to be
known to obtain EBV with reasonable accuracy. Four
candidate phenotypes are currently available to poten-
tially develop enteric methane emissions traits (de Haas
et al., 2017). These are methane production (g/d),
methane yield (g/kg of DMI), methane intensity (g/
kg of ECM or ADG), and residual methane production
(grams of methane regressed on DMI, BW, and ECM).
Research is required to understand the advantages and
limitations of each of these options. In addition, selec-
tive breeding takes advantage of genetic variation and
therefore requires multiple generations for its effects to
accumulate over time. Both pedigree-based selection
and genomic-based selection will require phenotyping
and genotyping large numbers of animals, which un-
derscores the importance of developing sensor and in-
dicator technologies, as described earlier. For example,
de Haas et al. (2021) estimate that phenotypes from
15,000 cows are required to achieve the reliability nec-
essary for genomic predictions on enteric methane pro-
duction within the Dutch breeding goal. In summary,
selective breeding can make a valuable contribution to
a portfolio of enteric methane mitigation options that
also include nutrition and management.
Socioeconomic Analysis
The discovery of new enteric methane mitigation op-
tions, by itself, is not enough for the dairy sector to
meet its environmental stewardship goals on climate
change. Mitigation options need to be deployed by a
substantial number of dairy farmers to achieve the
desired results. This task will become feasible when in-
novation in the biological and physical sciences, leading
to the development of new enteric methane mitigation
options, is accompanied by socioeconomic innovation
to drive their adoption. Innovation in economic and so-
cial fields is critical to creating favorable environments,
where adoption of enteric methane mitigation options
by dairy farmers is incentivized. The desirable goal is
to empower dairy farmers to incorporate mitigation
options into their operations because they are environ-
mentally and economically advantageous, recognized
through measurement and recording, and reputation-
ally rewarded.
Successful incorporation of enteric methane mitiga-
tion options into business models through pricing is
essential, but this is not the only requirement to ac-
celerate their adoption. The development of marginal
abatement cost curves is a valuable approach to rank
the cost-effectiveness of different enteric methane miti-
gation options and should be included in the socioeco-
nomic analyses (Eory et al., 2018). Complexity of use
associated with some mitigation options also represents
a significant barrier to adoption (Owen et al., 2012). For
example, the failure to adopt urea-ammonia treatment
to increase the nutritive value of straws, as reported
by Owen et al. (2012). This means that attention is
also needed to develop and test alternative financial
mechanisms, various modes of delivering technical as-
sistance, and innovative approaches to partnerships
to address existing barriers. Transparency concerning
milk production practices and enteric methane mitiga-
tion efforts is indispensable to ensure that consumers
trust the value chain that delivers nutritious milk and
dairy foods to them. Innovation, consensus building,
and clear communication are critical for dairy supply
chains to meet their climate change goals and for the
public to perceive them appropriately.
Innovation is also required in the regulatory environ-
ment in the United States because the current environ-
ment does not include clearly defined pathways specific
for options that target enteric methane mitigation.
For example, animal feed and health companies that
develop enteric methane inhibitors currently need to
pursue regulatory pathways that were developed to es-
tablish functional claims for drugs, such as compounds
to cure, prevent, treat, or mitigate disease conditions
or that change bodily structures or functions (United
States Food and Drug Administration, 2022). Different
regulatory mechanisms need to be developed that are
specific for environmental claims to incentivize innova-
tion in enteric methane mitigation.
Finally, the challenge of larger financial invest-
ments for enteric methane mitigation options is always
present. Private companies are currently investing to
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Journal of Dairy Science Vol. 105 No. Sym, 2022
develop enteric methane mitigation options without
clarity on how and when they may capitalize on market
opportunities, particularly if the options do not also of-
fer additional economic benefits. Associations and non-
governmental organizations are investing in research to
measure, test, and understand both the impacts and
the opportunities afforded by options that promise en-
teric methane mitigation. Yet, simultaneously, public
spending in the United States on agricultural research
and development to address climate change while in-
creasing food production is shrinking and is currently
below the level of private sector investment (Clancy et
al., 2016; Economic Research Service 2019). Govern-
ment is a critical funder of research and in many cases
represents the only funding available. As such, a need
exists to increase, reorganize, and leverage research
funding from public and private sources to encourage
scientific pursuits that can build the basis for innova-
tion by private funders looking to capitalize on market-
place opportunities.
EVALUATING ENTERIC METHANE MITIGATION
OPTIONS
The accurate estimation of emissions and remov-
als resulting from the adoption of enteric methane
mitigation options by dairy farmers requires integrated
systems approaches. For example, the quantification
of net greenhouse gas emissions associated with the
production and distribution of feed additives to miti-
gate enteric methane emissions requires following the
guidelines developed by the Livestock Environmental
Assessment and Performance Partnership (LEAP) of
the Food and Agriculture Organization of the United
Nations (FAO, 2020). A life cycle assessment approach
is required to conduct cradle-to-farm gate environmen-
tal impact analyses to account for upstream and down-
stream effects of mitigation options according to these
guidelines. Meta-analyses are also critical to quantify
the effectiveness of enteric methane mitigation options.
This is because the sign and magnitude of the response
often depend on the context and landscape in which
each dairy farm operates. The management and envi-
ronmental conditions, such as the animal life stage and
genetic makeup, additive dose, type of feeding, mitiga-
tion option delivery, and dietary composition, affect
the expected mitigation response. Adequate research
is needed for meta-analyses to be conducted for each
mitigation option.
Quantifying the effects of adding mitigation options
or changing milk production practices is extremely
difficult without the ability to model whole-farm sys-
tems (Kebreab et al., 2019). Whole-farm models are
also required to evaluate connections between system
components that physical research cannot practically
investigate and, in many instances, can provide infor-
mation less expensively and more quickly than physical
experimentation. Research is needed to support the
development of integrated models that simulate the
flows of carbon through the entire dairy farm under
different management and environmental conditions.
These models could benefit from the extensive amounts
of data currently collected on commercial dairy farms
(Cabrera et al., 2020). In addition, it is essential to
understand the implications that enteric methane miti-
gation options could have on the local, regional, and
global food systems. These different levels of aggrega-
tion represent an important challenge that can only
be addressed through the development, validation, and
application of whole-farm, landscape, and dairy sector
models.
GREENER CATTLE INITIATIVE COLLABORATIVE
STRUCTURE
The Greener Cattle Initiative was established to
function over the course of 5 years, with the expec-
tation that positive results will encourage funders to
extend the timeline and funds available. The collabora-
tion model for the program reflects the collaborative
structure defined as a consortium by Pisano and Ver-
ganti (2008)—namely, a closed participation model
with a flat governance. Focus on developing strong
relationships within the participants and identifying
and engaging with experts within their corresponding
networks will be critical to address the limitations asso-
ciated with the closed model involving few participants.
In addition, flexible but clearly defined rules and pro-
cesses are necessary to drive participant collaboration
toward common goals that are sometimes challenging
to achieve with flat governance structures.
A group of up to 10 participating organizations will
comprise a steering committee. This steering commit-
tee will determine the scientific scope, the strategic
direction, the project review and approval process, and
new participant recruitment. Each organization will
have one seat on the steering committee and will hold
a single vote. All decisions affecting requests for pro-
posals, projects awarded, or major decisions relative
to the initiative’s operations will be made by major-
ity vote. Both FFAR and DRI will function as final
arbiters when the decision-making process does not
result in a clear outcome. The program director will
be an individual hired by DRI to manage day-to-day
operations of the initiative according to the direction
set by the steering committee. The FFAR will act as
disbursement facilitator for all project funds to grant-
ees leveraging the infrastructure and processes it has
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Journal of Dairy Science Vol. 105 No. Sym, 2022
already developed for this purpose. Specific informa-
tion on how to submit proposals will become avail-
able after the program is launched and requests for
proposals are announced. Steering committee members
will receive knowledge of the results developed in all
projects before publication, enabling early evaluation
of their interests in licensing any corresponding intel-
lectual property.
CONCLUSIONS
Global challenges, such as enteric methane mitiga-
tion and its contribution to climate change, cannot
be solved by one organization. Addressing these chal-
lenges requires collaboration among many organiza-
tions and across different sectors. Collaboration under
the Greener Cattle Initiative is meant to establish
and articulate a clear path forward for coordinated
action among stakeholders in the public and private
sectors. Its purpose is to catalyze progress by pool-
ing resources and utilizing them more effectively for
experts to conduct research to identify, develop, and
validate enteric methane mitigation options. This
program represents an opportunity for participants
across the beef and dairy sectors to collaborate toward
a common goal. Involvement by farmers, feed compa-
nies, animal health and genetics companies, and other
value chain stakeholders will result in research efforts
that are informed by participants across the beef and
dairy sectors, targeting mitigation options that are
practical and implementable at scale. Focusing on
pre-competitive research enables leveraging invest-
ments and resources to create shared knowledge that
can be used as a platform for individual organizations
and companies, including competitors, to develop new
marketable mitigation options. This approach for pre-
competitive, collaborative research aims to accelerate
innovation on enteric methane mitigation and provide
lasting value to businesses, society, and the environ-
ment.
Public-private partnerships represent the most attrac-
tive opportunity for strategic collaboration to address
challenges facing the development of enteric methane
mitigation options in a coordinated effort. Collabora-
tion between the private and public sectors is critical
for identifying mitigation options and encouraging ac-
tion by dairy sector participants while continuing to
improve the availability of safe and nutritious milk and
dairy foods. The Greener Cattle Initiative is expected
to award up to 5 million dollars in research grant fund-
ing within the next 5 years, which will contribute to
advancing the voluntary greenhouse gas reduction goals
established by both the United States and global dairy
sectors.
ACKNOWLEDGMENTS
The Innovation Center for US Dairy provided funding
to ADSA as the exclusive sponsor for the symposium
titled “Production, Management and the Environment
Fall Webinar: Advances in Enteric Methane Mitigation
in Dairy Cattle—The Last Decade and Future Pros-
pects.” The authors have not stated any conflicts of
interest.
REFERENCES
Allen, M., K. Tanaka, A. Macey, M. Cain, S. Jenkins, J. Lynch, and
M. Smith. 2021. Ensuring that offsets and other internationally
transferred mitigation outcomes contribute effectively to limiting
global warming. Environ. Res. Lett. 16:074009. https: / / doi .org/ 10
.1088/ 1748 -9326/ abfcf9.
Allen, M. R., K. P. Shine, J. S. Fuglestvedt, R. J. Millar, M. Cain, D.
J. Frame, and A. H. Macey. 2018. A solution to the misrepresenta-
tions of CO2-equivalent emissions of short-lived climate pollutants
under ambitious mitigation. NPJ Clim. Atmos. Sci. 1:16. https: / /
doi .org/ 10 .1038/ s41612 -018 -0026 -8.
Arndt, C., A. N. Hristov, W. J. Price, S. C. McClelland, A. M. Pelaez,
S. F. Cueva, J. Oh, A. Bannink, A. R. Bayat, L. A. Crompton, J.
Dijkstra, M. A. Eugène, D. Enahoro, E. Kebreab, M. Kreuzer, M.
McGee, C. Martin, C. J. Newbold, C. K. Reynolds, A. Schwarm,
K. J. Shingfield, J. B. Veneman, D. R. Yáñez-Ruiz, and Z. Yu.
2022. Full adoption of the most effective strategies to mitigate
methane emissions by ruminants can help meet the 1.5°C target by
2030 but not 2050. Proc. Natl. Acad. Sci. USA 119:e2111294119.
Beauchemin, K. A., E. M. Ungerfeld, R. J. Eckard, and M. Wang.
2020. Fifty years of research on rumen methanogenesis: Lessons
learned and future challenges for mitigation. Animal 14:s2–s16.
https: / / doi .org/ 10 .1017/ S1751731119003100.
Cabrera, V. E., J. A. Barrientos-Blanco, H. Delgado, and L. Fadul-
Pacheco. 2020. Symposium review: Real-time continuous decision
making using big data on dairy farms. J. Dairy Sci. 103:3856–3866.
https: / / doi .org/ 10 .3168/ jds .2019 -17145.
Cain, M., J. Lynch, M. R. Allen, J. S. Fuglestvedt, D. J. Frame, and
A. H. Macey. 2019. Improved calculation of warming-equivalent
emissions for short-lived climate pollutants. NPJ Clim. Atmos. Sci.
2:29. https: / / doi .org/ 10 .1038/ s41612 -019 -0086 -4.
Clancy, M., K. Fuglie, and P. Heisey. 2016. US Agricultural R&D in
an Era of Falling Public Funding. Accessed Aug. 10, 2021. https:
/ / www .ers .usda .gov/ amber -waves/ 2016/ november/ us -agricultural
-r -d -in -an -era -of -falling -public -funding/ .
de Haas, Y., M. Pszczola, H. Soyeurt, E. Wall, and J. Lassen. 2017.
Invited review: Phenotypes to genetically reduce greenhouse gas
emissions in dairying. J. Dairy Sci. 100:855–870. https: / / doi .org/
10 .3168/ jds .2016 -11246.
de Haas, Y., R. F. Veerkamp, G. de Jong, and M. N. Aldridge. 2021.
Selective breeding as a mitigation tool for methane emissions from
dairy cattle. Animal 15:100294. https: / / doi .org/ 10 .1016/ j .animal
.2021 .100294.
Economic Research Service. 2019. Agricultural Research Funding in
the Public and Private Sectors. United States Department of Ag-
riculture. Accessed Aug. 10, 2021. https: / / www .ers .usda .gov/ data
-products/ agricultural -research -funding -in -the -public -and -private
-sectors/ .
Eory, V., S. Pellerin, G. Carmona Garcia, H. Lehtonen, I. Licite, H.
Mattila, T. Lund-Sørensen, J. Muldowney, D. Popluga, L. Strand-
mark, and R. Schulte. 2018. Marginal abatement cost curves for
agricultural climate policy: State-of-the art, lessons learnt and
future potential. J. Clean. Prod. 182:705–716. https: / / doi .org/ 10
.1016/ j .jclepro .2018 .01 .252.
FAO. 2020. Environmental performance of feed additives in livestock
supply chains—Guidelines for assessment—Version 1. Livestock
Environmental Assessment and Performance Partnership (FAO
Tricarico et al.: PRODUCTION, MANAGEMENT AND THE ENVIRONMENT

Journal of Dairy Science Vol. 105 No. Sym, 2022
LEAP). Food and Agriculture Organization of the United Nations.
https: / / doi .org/ 10 .4060/ ca9744en.
Global Dairy Platform. 2021. Pathways to Dairy Net Zero. Ac-
cessed Oct. 1, 2021. https: / / www .globaldairyplatform .com/
pathwaystodairynetzero/ .
Greening, C., R. Geier, C. Wang, L. C. Woods, S. E. Morales, M.
J. McDonald, R. Rushton-Green, X. C. Morgan, S. Koike, S. C.
Leahy, W. J. Kelly, I. Cann, G. T. Attwood, G. M. Cook, and R.
I. Mackie. 2019. Diverse hydrogen production and consumption
pathways influence methane production in ruminants. ISME J.
13:2617–2632. https: / / doi .org/ 10 .1038/ s41396 -019 -0464 -2.
Hristov, A. N., J. Oh, J. L. Firkins, J. Dijkstra, E. Kebreab, G. Wag-
horn, H. P. S. Makkar, A. T. Adesogan, W. Yang, C. Lee, P. J.
Gerber, B. Henderson, and J. M. Tricarico. 2013a. Special topics—
Mitigation of methane and nitrous oxide emissions from animal
operations: I. A review of enteric methane mitigation options. J.
Anim. Sci. 91:5045–5069. https: / / doi .org/ 10 .2527/ jas .2013 -6583.
Hristov, A. N., T. Ott, J. M. Tricarico, A. Rotz, G. Waghorn, A.
T. Adesogan, J. Dijkstra, F. Montes, J. Oh, E. Kebreab, S. J.
Oosting, P. J. Gerber, B. Henderson, H. P. S. Makkar, and J.
L. Firkins. 2013b. Special topics—Mitigation of methane and ni-
trous oxide emissions from animal operations: III. A review of ani-
mal management mitigation options. J. Anim. Sci. 91:5095–5113.
https: / / doi .org/ 10 .2527/ jas .2013 -6585.
Innovation Center for US Dairy. 2020. US Dairy Stewardship Com-
mitment. Accessed Sep. 23, 2021. https: / / www .usdairy .com/
getattachment/ f2bf0217 -3f4b -4b04 -9500 -45c85c61bc82/ u -s -dairy
-stewardship -commitment .pdf ?lang = en -US & ext = .pdf.
Kebreab, E., K. F. Reed, V. E. Cabrera, P. A. Vadas, G. Thoma, and
J. M. Tricarico. 2019. A new modeling environment for integrated
dairy system management. Anim. Front. 9:25–32. https: / / doi .org/
10 .1093/ af/ vfz004.
Knapp, J. R., G. L. Laur, P. A. Vadas, W. P. Weiss, and J. M. Tri-
carico. 2014. Invited review: Enteric methane in dairy cattle pro-
duction: Quantifying the opportunities and impact of reducing
emissions. J. Dairy Sci. 97:3231–3261. https: / / doi .org/ 10 .3168/ jds
.2013 -7234.
Lassen, J., and G. F. Difford. 2020. Genetic and genomic selection as a
methane mitigation strategy in dairy cattle. Animal 14:s473–s483.
https: / / doi .org/ 10 .1017/ S1751731120001561.
Le Quéré, C., R. M. Andrew, P. Friedlingstein, S. Sitch, J. Hauck, J.
Pongratz, P. A. Pickers, J. I. Korsbakken, G. P. Peters, J. G. Ca-
nadell, A. Arneth, V. K. Arora, L. Barbero, A. Bastos, L. Bopp,
F. Chevallier, L. P. Chini, P. Ciais, S. C. Doney, T. Gkritzalis, D.
S. Goll, I. Harris, V. Haverd, F. M. Hoffman, M. Hoppema, R. A.
Houghton, G. Hurtt, T. Ilyina, A. K. Jain, T. Johannessen, C. D.
Jones, E. Kato, R. F. Keeling, K. K. Goldewijk, P. Landschützer,
N. Lefèvre, S. Lienert, Z. Liu, D. Lombardozzi, N. Metzl, D. R.
Munro, J. E. M. S. Nabel, S. Nakaoka, C. Neill, A. Olsen, T. Ono,
P. Patra, A. Peregon, W. Peters, P. Peylin, B. Pfeil, D. Pierrot,
B. Poulter, G. Rehder, L. Resplandy, E. Robertson, M. Rocher, C.
Rödenbeck, U. Schuster, J. Schwinger, R. Séférian, I. Skjelvan, T.
Steinhoff, A. Sutton, P. P. Tans, H. Tian, B. Tilbrook, F. N. Tubi-
ello, I. T. van der Laan-Luijkx, G. R. van der Werf, N. Viovy, A. P.
Walker, A. J. Wiltshire, R. Wright, S. Zaehle, and B. Zheng. 2018.
Global carbon budget 2018. Earth Syst. Sci. Data 10:2141–2194.
https: / / doi .org/ 10 .5194/ essd -10 -2141 -2018.
Lynch, J., M. Cain, R. Pierrehumbert, and M. Allen. 2020. Demon-
strating GWP*: A means of reporting warming-equivalent emis-
sions that captures the contrasting impacts of short- and long-lived
climate pollutants. Environ. Res. Lett. 15:044023. https: / / doi .org/
10 .1088/ 1748 -9326/ ab6d7e.
Meale, S. J., M. Popova, C. Saro, C. Martin, A. Bernard, M. Lagree,
D. R. Yáñez-Ruiz, H. Boudra, S. Duval, and D. P. Morgavi. 2021.
Early life dietary intervention in dairy calves results in a long-
term reduction in methane emissions. Sci. Rep. 11:3003. https: / /
doi .org/ 10 .1038/ s41598 -021 -82084 -9.
Negussie, E., Y. de Haas, F. Dehareng, R. J. Dewhurst, J. Dijkstra, N.
Gengler, D. P. Morgavi, H. Soyeurt, S. van Gastelen, T. Yan, and
F. Biscarini. 2017. Invited review: Large-scale indirect measure-
ments for enteric methane emissions in dairy cattle: A review of
proxies and their potential for use in management and breeding
decisions. J. Dairy Sci. 100:2433–2453. https: / / doi .org/ 10 .3168/
jds .2016 -12030.
Owen, E., T. Smith, and H. Makkar. 2012. Successes and failures
with animal nutrition practices and technologies in developing
countries: A synthesis of an FAO e-conference. Anim. Feed Sci.
Technol. 174:211–226. https: / / doi .org/ 10 .1016/ j .anifeedsci .2012
.03 .010.
Patra, A. K. 2016. Recent advances in measurement and dietary miti-
gation of enteric methane emissions in ruminants. Front. Vet. Sci.
3:39. https: / / doi .org/ 10 .3389/ fvets .2016 .00039.
Pisano, G. P., and R. Verganti. 2008. Which kind of collaboration is
right for you? Harv. Bus. Rev. 86:78–86. https: / / hbr .org/ 2008/ 12/
which -kind -of -collaboration -is -right -for -you.
Pitta, D. W., A. Melgar, A. N. Hristov, N. Indugu, K. S. Narayan, C.
Pappalardo, M. L. Hennessy, B. Vecchiarelli, V. Kaplan-Shabtai,
M. Kindermann, and N. Walker. 2021. Temporal changes in total
and metabolically active ruminal methanogens in dairy cows sup-
plemented with 3-nitrooxypropanol. J. Dairy Sci. 104:8721–8735.
https: / / doi .org/ 10 .3168/ jds .2020 -19862.
US EPA (United States Environmental Protection Agency). 2021. In-
ventory of U.S. Greenhouse Gas Emissions and Sinks. Accessed
Apr. 16, 2021. https: / / www .epa .gov/ ghgemissions/ inventory -us
-greenhouse -gas -emissions -and -sinks.
United States Food and Drug Administration (FDA). 2022. New
Animal Drug Applications. Accessed Feb. 25, 2022. https: / / www
.fda .gov/ animal -veterinary/ development -approval -process/ new
-animal -drug -applications.
ORCIDS
J. M. Tricarico https: / / orcid .org/ 0000 -0002 -2101 -1564
Y. de Haas https: / / orcid .org/ 0000 -0002 -4331 -4101
A. N. Hristov https: / / orcid .org/ 0000 -0002 -0884 -4203
E. Kebreab https: / / orcid .org/ 0000 -0002 -0833 -1352
F. Mitloehner https: / / orcid .org/ 0000 -0002 -9267 -1180
D. Pitta https: / / orcid .org/ 0000 -0002 -3102 -9119
Tricarico et al.: PRODUCTION, MANAGEMENT AND THE ENVIRONMENT