Utilizing Clostridium autoethanogenum for dietary protein in aquafeeds: Current progress in research and future perspectives

The aquaculture sector faces sustainability challenges due to unsustainable feedstuffs. To address this, there's a continuous search for alternatives to traditional aquafeed protein sources such as fishmeal. Clostridium autoethanogenum is a novel aquafeed protein source with a long-standing application in the bio-energy industry. With 80-89% crude protein content on a dry matter basis, Clostridium autoethanogenum protein (CAP) has gained attention in nutrition research for aquaculture species. This study aimed to review CAP utilization in aquafeed, examining its nutritional value and impacts on aquatic animals' growth, feed efficiency, digestion, absorption, and immune response. Research suggests promising potential for CAP in aquafeed, showing potential for achieving complete fishmeal replacement without compromising growth performance and immune response in select aquaculture species. Nonetheless, higher inclusion levels show adverse effects on the health status of certain fish species, indicating variability among species to utilize CAP-based diets. Further investigations are required to understand this variability in outcomes reported among species.