Modulation of Gut Flora and Its Application in Food Animal Products

Modulation of the gut microbiota with feed and/or feed additives has become a promising and important strategy for the improvement of animal/human health and performance in recent years. Indeed, host genetics, age, infection/inflammation, exposure to antibiotics, and diet are the main factors involved in the composition of the host intestinal microbiota and intestinal environment. Sustainable feed additives can also be safe, consumer-friendly, and effective, and commonly have a beneficial effect on host health. Sustainable feed additives include plant by-products and/or prebiotics, probiotics, and animal-derived feed additives. Recent studies have reported that many natural plant by-products are not only rich in polyphenolic compounds but they are also antioxidant, anti-inflammatory, anticancer, and act as antimicrobial, antiviral, cardioprotective, neuroprotective, and hepatoprotective compounds. Probiotics can also be a handful in maintaining the homeostasis in host gut in the presence or absence of prebiotics. In this chapter, we aim to focus on the factors involved and the mechanism by which the growth and the gut microflora modulation are done and ultimately improve the animal/host health and performance. Furthermore, the effect of various factors, specifically feed additives, on growth promotions of various animal food industries such as poultry, cattle, and swine will be also discussed.