An exploration on greenhouse gas and ammonia production by insect species suitable for animal or human consumption

• Published in: PloS one 2010-12, Vol.5 (12), p.e14445
• Main Authors: Oonincx, Dennis G A B, van Itterbeeck, Joost, Heetkamp, Marcel J W, van den Brand, Henry, van Loon, Joop J A, van Huis, Arnold
• Format: Article
• Language: English
• Subjects: Acheta domesticus; Acidic soils; Acidification; Air pollution; Ammonia; Ammonia - chemistry; Animal Feed; Animal protein; Animals; Anthropogenic factors; Blaptica dubia; Carbon dioxide; Carbon Dioxide - chemistry; Cattle; Chemical Biology/Small Molecule Chemistry; Climate change; Climate change causes; Crickets; Ecology/Global Change Ecology; Edible insects; Emissions; Environmental impact; Exploration; Feed conversion; Food sources; Gases; Global temperature changes; Greenhouse Effect; Greenhouse gases; Growth rate; Humans; Insecta; Insects; Life cycle analysis; Life cycle engineering; Life cycles; Livestock; livestock buildings; Locusta migratoria; Manures; metabolic-rate; Methane; Methane - chemistry; Natural gas; Nitrification; Nitrous oxide; Nitrous Oxide - chemistry; Nitrous oxides; Nutrition; Orthoptera; Pachnoda marginata; pachnoda-ephippiata coleoptera; Proteins; reduced oxygen concentrations; respiration; Scarabaeidae; Species; Swine; Temperature; Tenebrio molitor; weaned pigs
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0014445

Greenhouse gas (GHG) production, as a cause of climate change, is considered as one of the biggest problems society is currently facing. The livestock sector is one of the large contributors of anthropogenic GHG emissions. Also, large amounts of ammonia (NH(3)), leading to soil nitrification and acidification, are produced by livestock. Therefore other sources of animal protein, like edible insects, are currently being considered. An experiment was conducted to quantify production of carbon dioxide (CO₂) and average daily gain (ADG) as a measure of feed conversion efficiency, and to quantify the production of the greenhouse gases methane (CH₄) and nitrous oxide (N₂O) as well as NH₃ by five insect species of which the first three are considered edible: Tenebrio molitor, Acheta domesticus, Locusta migratoria, Pachnoda marginata, and Blaptica dubia. Large differences were found among the species regarding their production of CO₂ and GHGs. The insects in this study had a higher relative growth rate and emitted comparable or lower amounts of GHG than described in literature for pigs and much lower amounts of GHG than cattle. The same was true for CO₂ production per kg of metabolic weight and per kg of mass gain. Furthermore, also the production of NH₃ by insects was lower than for conventional livestock. This study therefore indicates that insects could serve as a more environmentally friendly alternative for the production of animal protein with respect to GHG and NH₃ emissions. The results of this study can be used as basic information to compare the production of insects with conventional livestock by means of a life cycle analysis.