Climate stress impacts on livestock health: Implications for farming livelihoods and animal disease in Karnataka, India

Abstract

Abstract Understanding the impact of climate change on livestock health is critical to safeguarding global food supplies, economies, and farming livelihoods. We evidence, through exploration of secondary data informed by a rapid ethnographic assessment of farming livelihoods in Karnataka, India, that both precipitation and vapour pressure are key climate variables relating to outbreaks of haemorrhagic septicaemia (HS), anthrax (AX), and black quarter (BQ) across the Indian state of Karnataka. We then developed a risk classification tool that assesses how disease risk varies in Karnataka at present and in possible future scenarios. Temperature and maximum temperature are negatively correlated with HS, AX, and BQ, indicating that regions experiencing a cool (but still hot) climate with increasingly wetter, more humid conditions are at high risk of future outbreaks. Principal component analyses revealed the southwest India monsoon and winter periods to be the most strongly correlated with HS, AX, and BQ outbreaks. Vapour pressure, a proxy for humidity, has a positive relationship with these specific livestock diseases. Certain environmental conditions increase the incidence of some bacterial diseases and conditions that mimic their symptoms, and thus also risk driving up the use of antibiotics and the emergence of antimicrobial resistance (AMR) in regions under stress. This methodology can be replicated to investigate other diseases and regions, as long as the climate and epidemiological data cover similar time periods. This evidence highlights the need for greater synergies between climate change and One Health research and policy. One Health Impact Statement We have taken a transdisciplinary approach, which expands out of One Health to include climate science and participatory research with farmers and livestock industry consultants, to investigate the relationship between factors related to climate (surface temperatures, rainfall, humidity) and outbreaks of livestock-related bacterial diseases. This is especially relevant to the One Health approach as it attempts to integrate findings between not only the science of disease but also the science of climate change as a driver of disease, and address problems that could arise within the public and private sectors (local farming, livestock health, government policy etc.). Providing spatial context to climate-associated disease risk across the Indian state of Karnataka will benefit: local farmers who may already be practising, or are transitioning to, more intensive livestock farming; policymakers; and private sector companies who are planning for future investments. Such expansion needs to be undertaken with full awareness of potentially heightened disease risk. Our transdisciplinary approach is borne from the observations of famers’ lived experiences of challenges to their livelihoods and facilitates the use of climate datasets that may not have been primarily collected for, or used by, disease-related studies to map long-term epidemiological risk. This demonstrates the pragmatic impact that such transdisciplinary projects can have, by providing interpretations of observed risks to animal health (highlighted by social scientists during engagement with practitioner communities) that Earth Scientists were then able to quantify, proving links that would otherwise not have been evidenced. The use of disease data sourced from local institutions, including the Government of India and research laboratories, can inform plans for the application of pragmatic solutions to local challenges by local farmers who are primarily impacted by the challenges highlighted in the research.