Lewis Griffiths


A personal viewpoint from Lewis Griffiths, retiring Chair of VetSalus

Discussions about the formation of VetSalus began in 2016 and the organisation was formally launched in 2018. Since its inception, I have been involved in a number of roles, most recently as Chair. Last month I resigned that position and will shortly resign as a director. I am pleased to write that this is not some grand political gesture; I have no concerns about the business direction and management of VetSalus. It is simply time for a change. (And anyway, too few politicians resign, these days, when they really should!)

During the seven years of my involvement with this group, there has already been a considerable amount of change. Initially, there was some confusion about exactly what an international group of veterinarians could achieve in the field of food production from farmed animals. This has become clearer over time and the business is now firmly focused on providing leadership, education and opportunities for veterinarians, and their support teams, particularly in the field of One Health. Much has been achieved to date but there is much more left to do.



One Health, of course, provides a broad perspective on which to base business activities. Antimicrobial usage and animal welfare issues are legion but VetSalus has chosen to primarily address the overarching topic of sustainability and much of our recent energy has been aimed at providing educational resources in this area.

Reversing climate change is a fundamental reason for developing more sustainable methods of food production. If we accept a simplified definition of sustainable food production as: “meeting the needs of the present without compromising the ability of future generations to meet their needs,” it is easy to envisage how the efficiency of food production from a planet ravaged by floods and wildfire, and with sea levels steadily rising will impact on future generations. And in a world challenged by a rising population, which is likely to peak mid century at around ten billion, the demands of future populations for food will be very significant.

It is worrying to note that 2023 has been declared the warmest year since modern records began. Indeed there are now considerable concerns that the rate of warming has accelerated to a point where its ability to change the climate is larger and faster than scientists have previously anticipated.

To quote Gavin Schmidt writing recently in Nature (1):

“For the past nine months, mean land and sea surface temperatures have overshot previous records each month by up to 0.2 °C — a huge margin at the planetary scale. It’s humbling, and a bit worrying, to admit that no year has confounded climate scientists’ predictive capabilities more than 2023 has.”

While he implicates a number of special factors which have impacted upon this year, including the arrival of El Nino, increased solar activity and the fallout from the Tongan volcanic eruption, there is still no scientific explanation that completely explains this rapid acceleration in temperatures.

As I move on from my role as VetSalus Chair there is one nagging issue which, I believe, all actors working in this area, particularly scientists, journalists and politicians, have failed to fully address: methane. Methane is undoubtedly a major greenhouse gas and its involvement in the chemistry that is causing an increase in the mean temperature of this planet is certain but complex. We know that the impact of methane is shorter in its duration compared to other major greenhouse gases, like CO2. But, in my opinion, the full understanding of methane and its place in the carbon cycle has not been well communicated to decision makers and the general public. And that is a responsibility which rests upon the shoulders of all us involved in science communication.

The debate on how best to measure the impact of methane has been detailed and prolonged. Metrics such as GWP100 and GWP*, and more recently GWP20, have been traded by the technically minded few in an acronymic storm, with few members of the general public fully understanding the argument, or even what all the fuss is about. But there is, I believe, a more fundamental aspect of the methane debate that has totally escaped the attention of many: methane has two major sources.

  1. Biogenic: as part of the carbon cycle involving living beings, be they plant or animal in origin; every carbon atom involved is part of a closed cycle, sometimes in the air, sometimes in the soil and sometimes inside plants and animals; sometimes as methane and sometimes as CO2 and sometimes as other complex organic (2) chemicals. There are two important points here: given a stable animal population, no additional carbon is released into the atmosphere, and all plants as well as animals are intimately involved: plants release methane too!
  2. Thermogenic (fossil fuels) : carbon which is released from long stored sources such as coal, gas and oil and which is additive to the impacts of the biogenic carbon cycle. All thermogenic carbon is additive; these are new carbon atoms released into the atmosphere.

Over the last 10,000 or so years, hunter-gatherers changed and began improving the efficiency of their food production, using, initially at least, largely sustainable farming techniques to feed a growing, city based population. It is only during the last 250 years or so that mankind has learned how to utilise and release fossilised carbon on a significant scale, to enhance that productivity and feed the needs of a rapidly growing population; historians label this the ‘industrial revolution’ but it might just as well be called the ‘neo-carbon explosion’. The impacts of modern farming, especially since the post war period when nitrogenous fertilisers have become a cornerstone of food production for both arable and animal agriculture, have been significant but they are dwarfed beside the impacts of fossilised carbon used in other industries, transport and modern housing, which are all required to meet the needs of an expanding population. Agriculture in total, including all arable and forestry sources, accounts for just under 25% of mankind’s total greenhouse gas emissions (3),with animals representing just over half of that total. It is too simplistic to suggest, as many do, that by removing all farm animals from the planet we can cut those emissions by half.


Tractor & spreader


Farm animals remain important contributors to soil health while providing high quality protein, other nutrients and by-products. And while methane is the most important contributor to agricultural emissions, it is important to remember that emissions are only part of the complexity of the biogenic carbon cycle. Soil sequestration, for example, is a critical, but as yet poorly studied, element of this cycle. It was not so long ago that my grandfather, knowing nothing of modern fertilisers, was happily spreading farm manure on his Welsh farm fields, using a horse and cart; a practice still common in many less developed areas of the globe which remains essential to much arable production.

I am not suggesting for one minute that we should ignore the impacts of modern farming on the environment and biodiversity and let it loose, unmitigated, to feed the expanding world population. At VetSalus, we have identified a major role for veterinarians, working with their clients, to reduce farm carbon footprints and improve the efficiency of food production from farm animals. But this improvement can only come from three major areas of change:

  1. By way of nutritional inputs, (and much science is being currently directed at methane inhibitors and other dietary supplements that modify ruminant digestion.)
  2. from genetics and breeding: again much work is being directed at the selection of genotypes which produce less methane per kilogram of food ingested.
  3. and from management: particularly improvement in animal health, reproduction, and welfare.

An interesting article on BBC news recently reviewed the range of research that New Zealand is engaged in, as it attempts to meet its 2030 carbon footprint target: (4) its largely biogenic carbon footprint I should add. New Zealand’s agricultural industry is admired around the world as one of the most efficient producers of animal protein from pasture. Ruminant digestion remains one of the few ways we can produce quality protein from cellulose.

I read recently of the development of a satellite which will scan the planet for methane emissions and thus enable fixers to zoom in and reduce them. This sounds like the sort of commonsense science that may just have some practical results and, as I view the first reports (5) of methane density, it is clear that the high outputs are in areas of melting tundra, leaking gas and oil wells and dense populations, potentially from landfill dumps; both New Zealand and the United Kingdom do not have any densely coloured dots. Where has all the agricultural methane gone? In further support of the importance of fossil fuel sources of greenhouse gases, a report from the Carbon Majors Database, recently reported in the Guardian (6), lists 57 companies who between them, since the 2016 Paris COP meeting, account for 80% of global emissions. It is not surprising to learn that the largest offenders are suppliers of oil, gas and coal but it is maybe a surprise to learn that 65% are government owned and that emissions continue to increase.

I also read with considerable interest, the recent reports of farmer protests in Europe, including post BREXIT U.K. I suggest that these protests are the result of the clumsy introduction of politically acceptable solutions by governments, who can afford to antagonise farmers, as long as they keep the populace well fed. And while farmers reduce or cease production for sound economic reasons like “it doesn’t pay to farm here anymore”, potentially exporting our emissions elsewhere; and concerns around food supply chains grow, the role of supermarkets in marginalising incomes from farming and horticultural businesses, merits few headlines.

May you live in interesting times”; that ancient curse is more relevant than ever today. The medium term solution to our current predicament, the Catch 22 of feeding an expanding population while reducing carbon outputs from agriculture, can only come from the application of sound, science based solutions. But many believe that, as yet unspecified, new technologies and even artificial intelligence (A.I.) will provide that solution? Waiting for new technology is just another form of procrastination, which Don Marquis defined neatly nearly 100 years ago as,”the art of keeping up with yesterday.” The BBC article on New Zealand’s initiatives concluded that nothing is working yet! These sorts of complex solutions take time to develop. And production in the meantime must continue. Progress towards net zero is awash with potential ‘solutions’ that have delivered nothing yet (7).

Having drafted this article, I asked Chat GPT, the commonly used A.I. app, to write it for me; “write me a review article on methane from a veterinary perspective” I asked. At a simplistic, superficial level it produced something that nearly every politician on the planet could (and should) read; many may also understand it. I particularly enjoyed its conclusion, which I have not edited:

By applying a holistic approach that integrates animal nutrition, herd management, and veterinary medicine, veterinarians can play a crucial role in promoting sustainable livestock production systems that minimize environmental impact while ensuring animal health and welfare. Continued collaboration between veterinary scientists, producers, policymakers, and other stakeholders is essential to develop and implement effective strategies for mitigating methane emissions and advancing the sustainability of livestock production.

So A.I. (an acronym which continues to mean something entirely different in animal reproduction!) may well form part of the solution; maybe it will assist in the efficient delivery of solutions. But it will not produce the ‘magic bullet’. I do not believe that any VetSalus consultant needs worry about being replaced by A.I. anytime soon.

In conclusion, (and, I contend, any departing Chair has the right to a departing rant like this,) in an ideal world politicians would more closely heed the advice of expert scientists and ignore the lobbying of other interested parties. Surely the lessons, which are slowly being learned post COVID reinforce this position? If they are unsure exactly what they should do next, maybe they could ask A.I. but the message from this departing Chair to them is simple:

Agricultural initiatives will continue to reduce methane emissions while improving productivity but it is not agriculture that is killing the planet; focus your attention on the generators of CO2 from fossil fuels and if you don’t know who they are, check your party’s donation database, because, I suspect they will be found near the top of that list! And please remember that, while planting trees or making improvements in agricultural systems will, while working biogenically, take some 10 to 20 years to absorb significant quantities of carbon, insulating a house, fixing a leaking oil well or installing a heat pump can have an immediate impact.

By overly focusing on the contributions of agricultural methane, with all its complexity, are we not doing things the wrong way around? Are we not missing out on the low hanging fruit? Or as my grandfather would say, “You’ve got the cart in front of the horse boy!”



  1. https://www.nature.com/articles/d41586-024-00816-z?utm_source=Live+Audience&utm_campaign=51b1f44375-briefing-an-20240322&utm_medium=email&utm_term=0_b27a691814-51b1f44375-51823720&mc_cid=51b1f44375&mc_eid=9851f509f6
  2. organic = the chemistry of carbon here, not a farming methodology
  3. Smith P., M. Bustamante, H. Ahammad, H. Clark, H. Dong, E.A. Elsiddig, H. Haberl, R. Harper, J. House, M. Jafari, O. Masera, C. Mbow, N.H. Ravindranath, C.W. Rice, C. Robledo Abad, A. Romanovskaya, F. Sperling, and F. Tubiello, 2014: Agricul- ture, Forestry and Other Land Use (AFOLU). In: Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Edenhofer, O., R. Pichs-Madruga, Y. Sokona, E. Farahani, S. Kadner, K. Seyboth, A. Adler, I. Baum, S. Brunner, P. Eickemeier, B. Kriemann, J. Savolainen, S. Schlömer, C. von Stechow, T. Zwickel and J.C. Minx (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
  4. https://www.bbc.com/future/article/20231214-how-new-zealand-is-reducing-methane-emissions-from-farming
  5. https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-5P/Mapping_methane_emissions_on_a_global_scale
  6. https://www.theguardian.com/environment/2024/apr/04/just-57-companies-linked-to-80-of-greenhouse-gas-emissions-since-2016?utm_term=660e5543b3db2e18c51e3858f71aafac&utm_campaign=BusinessToday&utm_source=esp&utm_medium=Email&CMP=bustoday_email
  7. https://vetsalus.com/news/2023/07/opinion-piece-zeroing-net-zero


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Appendix 1

For your interest, I have appended the unedited, Chat GPT article below:

Title: Understanding Biogenic Methane in Livestock Production: A Veterinary Perspective. Introduction: As concerns about climate change continue to rise, there is growing scrutiny on the environmental impact of various industries, including agriculture. Livestock production, in particular, has come under scrutiny due to its significant contribution to greenhouse gas emissions, particularly methane. While methane emissions from livestock are often portrayed as a major contributor to climate change, it is crucial to understand the complex relationship between livestock, methane production, and sustainable agricultural practices from a veterinary perspective.

The Biogenic Methane Process: Methane is produced in the digestive systems of ruminant animals through a natural process called enteric fermentation. In the rumen, complex carbohydrates from forages and grains are broken down by microbes into volatile fatty acids and gases, including methane. This methane is then released by belching or eructation. While methane emissions from livestock are a natural part of the carbon cycle, their environmental impact depends on various factors, including animal diet, management practices, and herd health.

Veterinary Role in Mitigating Methane Emissions: Veterinarians play a critical role in implementing strategies to mitigate methane emissions from livestock production while ensuring animal health and welfare. One approach is optimizing animal nutrition to improve feed efficiency and reduce methane production per unit of feed consumed. This includes formulating diets with ingredients that promote efficient rumen fermentation, such as high-quality forages, dietary additives, and feed supplements.Furthermore, veterinarians can advise on herd management practices that minimize methane emissions, such as optimizing grazing systems, improving manure management, and implementing rotational grazing to maximize pasture productivity and soil health. Additionally, veterinarians can play a vital role in monitoring and managing herd health to prevent diseases that can increase methane emissions, such as ruminal acidosis or bloat.

Research and Innovation: Continued research and innovation are essential for developing sustainable solutions to reduce methane emissions from livestock production. Veterinary scientists are actively involved in researching novel feed additives, microbial interventions, and genetic selection strategies aimed at mitigating methane production while maintaining animal productivity and health. Moreover, advancements in precision livestock farming technologies, such as real-time monitoring of rumen function and microbial populations, offer promising opportunities to optimize feed efficiency and reduce methane emissions on an individual animal basis.

Conclusion: In conclusion, biogenic methane emissions from livestock production present both challenges and opportunities for the veterinary profession. By applying a holistic approach that integrates animal nutrition, herd management, and veterinary medicine, veterinarians can play a crucial role in promoting sustainable livestock production systems that minimize environmental impact while ensuring animal health and welfare. Continued collaboration between veterinary scientists, producers, policymakers, and other stakeholders is essential to develop and implement effective strategies for mitigating methane emissions and advancing the sustainability of livestock production.