A review: Flavonoid; A Phyto-nutrient and its impact in livestock animal nutrition

Flavonoids, recognized as phyto-nutrients and natural bioactive compounds in animal feed, play a pivotal role in enhancing the quality of animal products and bolstering animal health. Flavonoids cannot be internally synthesized by humans and animals; instead, they are sourced from plants. They are characterized by diverse phenolic structures, and are abundant in a variety of sources such as fruits, vegetables, grains, bark, roots, stems, and flowers. Their multifaceted advantages encompass promoting animal growth, improving the quality of animal products, serving as feed additives, and acting as alternatives to antibiotics in animal production. On average, individuals are estimated to ingest 10–100 mg of flavonoids daily through diverse food items. However, a critical assessment reveals that achieving an optimal dietary intake of flavonoids is challenging due to the vast array of available types, their widespread distribution across various plants, and the varied consumption patterns in both humans and animals, which remain relatively low. Flavonoids exhibit inhibitory effects on both Gram-positive and Gram-negative bacteria, yet the comprehensive mechanisms underlying their antibacterial properties are not fully elucidated. This review explored the impact of flavonoids on diabetes mellitus, their antioxidant effects, and their antimicrobial properties. Finally, the mechanism of operation and the influence of flavonoids on ruminant animal nutrition were also assayed.