Authors: Heinz Meissner, James Blignaut, Hendrik Smith and Linde Du Toit
Cattle have been the focus of an intense debate between those concerned about the possible negative effects on global warming, land degradation, food competition and human health, and those who are positive toward the possible role of cattle in maintaining global socio-economic and environmental sustainability. Here we reviewed the pros and cons in view of a projected increase in demand for animal-based foods and therefore in cattle numbers. Analyses of cattle numbers and foods from various literature sources suggest gross overestimation towards 2050. Nevertheless, the importance of cattle to the global socio-economy, world trade and human sustenance, particularly in the developing world, is shown to be indispensable. Also, animal-based foods are shown to be vital to human health and development, and contrary to many claims to the opposite, there is very little evidence that animal-based foods are associated with serious non-communicable diseases, if consumed in recommended portions. With respect to global warming, cattle are responsible for a significant portion of methane emissions. However, the atmospheric accumulation of methane from cattle is overestimated due to methane’s short lifespan, recent calculations of enteric fermentation and methane’s warming potential, in addition to the role of cattle in carbon sequestration and being a sink. Since carbon sequestration has more potential than emission reduction in limiting global warming, photosynthetic capacity should be maximised. This is promoted by conservation of the world’s grasslands and using cattle and other herbivore livestock as grazing stimulants to enhance photosynthesis. Also, in crop production, by using cattle to provide organic fertiliser and graze cover crops in regenerative methodology, soil organic carbon and soil health are improved, to the eventual benefit of soil storage of atmospheric carbon. It is concluded that whereas concerns about animal welfare, zoonosis and antimicrobial resistance should be addressed, the call for a reduction in global cattle numbers because of the perceived negatives is unwarranted. A reduction in cattle numbers will limit carbon sequestration and largely defeat the objective of limiting global warming.