Deforestation, greenhouse gas emissions, biodiversity loss, nitrogen pollution -- today's agricultural feed cultivation for cattle, pigs and chicken comes with tremendous impacts for the environment and climate. Cultivating feed in industrial facilities instead of on croplands might help to alleviate the critical implications in the agricultural food supply chain. Protein-rich microbes, produced in large-scale industrial facilities, are likely to increasingly replace traditional crop-based feed. A new study now published in the journal Environmental Science & Technology for the first time estimates the economic and environmental potential of feeding microbial protein to pigs, cattle and chicken on a global scale. The researchers found that by replacing only 2 percent of livestock feed by protein-rich microbes, more than 5 percent of agricultural greenhouse gas emissions, global cropland area and global nitrogen losses could each be decreased. "Chicken, pigs and cattle munch away about half of the protein feed cultivated on global croplands," says Benjamin Leon Bodirsky, author of the study from the Potsdam Institute for Climate Impact Research (PIK, member of the Leibniz Association). Without drastic changes to the agro-food system, the rising food and animal feed demand that comes with our meat-based diets will lead to continuous deforestation, biodiversity loss, nutrient pollution, and climate-impacting emissions. "However, a new technology has emerged that might avoid these negative environmental impacts: Microbes can be cultivated with energy, nitrogen and carbon in industrial facilities to produce protein powders, which are then fed instead of soybeans to animals. Cultivating feed protein in labs instead of using croplands might be able to mitigate some environmental and climatic impacts of feed production. And our study expects that microbial protein will emerge even without policy support, as it is indeed economically profitable."