Recent Developments in the Application of Filamentous Fungus Aspergillus oryzae in Ruminant Feed.

Simple Summary: Ruminant farming, which includes animals like cows and sheep, is resource-intensive and this is becoming more of an issue as the human population grows. People are also worried about the use of antibiotics in animal feed. Scientists are looking for new, sustainable ways to feed these animals to improve their health and production without antibiotics. One promising solution is using edible fungi, like Aspergillus oryzae. This fungus can provide important nutrients, such as proteins, which are usually obtained from plants or animals. By adding these fungi to animal feed, it can reduce the need for conventional protein sources and antibiotics, enhancing the quality of the feed and the well-being of the animals. This review paper explores the effects of including an Aspergillus oryzae fungal biomass in ruminant feed and explains how this fungus can be grown on organic residues. In summary, using Aspergillus oryzae in animal feed provides essential nutrients that can support animal health and productivity, all of which are valuable to society. The resource-intensive nature of the ruminant farming sector, which has been exacerbated by population growth and increasing pressure to reduce feed antibiotics and growth promoters, has sparked interest in looking for sustainable alternative feed sources to enhance ruminant production efficiency. Edible filamentous fungi, rich in macronutrients like proteins, offer promise in reducing the reliance on conventional protein sources and antimicrobials to improve feed quality and animal performance. The inclusion of single-cell proteins, particularly filamentous fungi, in ruminant feed has long been of scientific and industrial interest. This review focuses on the potential application of the extensively studied Aspergillus oryzae and its fermentation extracts in ruminant nutrition. It provides an overview of conventional ruminant feed ingredients, supplements, and efficiency. Additionally, this review analyzes the re-utilization of organic residues for A. oryzae cultivation and examines the effects of adding fungal extracts to ruminant feed on ruminal digestibility and animal performance, all within a circular bioeconomy framework. [ABSTRACT FROM AUTHOR]