Industrial microbes could feed cattle, pigs and chicken

Without drastic changes to the agro-food system, the rising food and animal feed demand that comes with the meat-based diets will lead to continuous deforestation, biodiversity loss, nutrient pollution, and climate-impacting emissions.

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.

These are in a nutshell the main findings of new study published in the journal Environmental Science & Technology. The authors of the study, an international scientific team, for the first time estimate the economic and environmental potential of feeding microbial protein to pigs, cattle and chicken on a global scale.

Small feed changes could have a substantial environmental impact

The study is based on computer simulations that assess the economic potential and environmental impacts of microbial protein production until the middle of the century. The simulations show that globally, between 175−307 million tons of microbial protein could replace conventional concentrate feed like soybeans. So by replacing just roughly two per cent of the livestock feed, pressure on deforestation, agricultural greenhouse gas emissions and nitrogen losses from cropland could be decreased by more than five per cent.

“In practice, breeding microbes like bacteria, yeast, fungi or algae could substitute protein-rich crops like soybeans and cereals. This method was originally developed for space travel and uses energy, carbon and nitrogen fertilisers to grow protein-rich microbes in the lab,” explains co-author of the study Ilje Pikaar, from the University of Queensland in Australia.

Microbial protein alone does not make agriculture sustainable

“Feeding microbial protein would not affect livestock productivity,” stresses author Isabelle Weindl from the German Potsdam Institute for Climate Impact Research (PIK). “In contrast, it could even have positive effects on animal growth performance or milk production”.

But although the new technology is economically profitable, its adoption might still face constraints such as habitual factors in farm management, risk-aversion towards new technologies, or lacking market access. ”However, pricing environmental damages in the agricultural sector could make this technology even more economically competitive,” says Weindl.

“Our findings clearly highlight that the switch to microbial protein alone will not be enough for sustainably transforming our agriculture,” says co-author Alexander Popp from PIK. To reduce the environmental impact of the food supply chain, major structural changes in the agro-food system are required as well as changes in human dietary patterns towards more vegetables.

(PIK/wi)

For more information:

Article: Ilje Pikaar, et al., (2018): Decoupling Livestock from Land Use through Industrial Feed Production Pathways. Environmental Science and Technology [DOI:10.1021/acs.est.8b00216]

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