Effects of Fructooligosaccharides on Intestinal Health of Livestock

In aquaculture production, the unreasonable use of antibiotics will lead to bacterial resistance, destroy animal intestinal health and body immunity, and its residues in meat products and the environment will eventually affect human health. China has completely banned the addition of growth-promoting antibiotics in feed. Therefore, it is increasingly important to find additives that have the same efficacy as antibiotics to alleviate the decline in production performance and increase in mortality of livestock and poultry. The effect of probiotics on intestinal health has been confirmed, but due to their harsh storage conditions, the effect of using them in feed is unstable. Prebiotics are considered to be a good substitute. This time, let us take a look at the impact of the representative substance of prebiotics - fructooligosaccharides on the intestinal health of livestock.

FOS is resistant to high temperature, has good solubility and stability, and its sweetness is slightly lower than that of sucrose. It can inhibit the aging of starch, is not easy to color, has good alkali resistance and mildew resistance. These physical and chemical properties make FOS can be used as feed additives with excellent performance. In addition to improving the production performance of livestock and poultry by promoting growth, reducing diarrhea and mortality, FOS can also promote the intestinal health of livestock and poultry by regulating intestinal flora, intestinal fermentation, maintaining the shape of intestinal mucosa and improving body’s immunity.

FOS can prevent the colonization of exogenous pathogenic bacteria in the intestinal tract and the overgrowth of endogenous opportunistic pathogenic bacteria, thereby maintaining the intestinal microecological balance. A variety of digestive enzymes secreted by animals cannot hydrolyze the β-1,2 glycosidic bonds of FOS, so most FOS can pass through the stomach and small intestine smoothly. While beneficial bacteria in the large intestine such as lactobacillus, bifidobacteria, etc. can cut off β-1,2 glycosidic bonds to proliferate, but harmful bacteria cannot secrete these enzymes. After the beneficial bacteria proliferate, they form a bacterial film on the intestinal mucosa, making it difficult for pathogenic bacteria to colonize. At the same time, beneficial bacteria can also ferment a large amount of fatty acids such as acetic acid, propionic acid and lactic acid produced by FOS, increase intestinal acidity, and directly inhibit the growth of pathogenic bacteria.

FOS can selectively stimulate the growth of bifidobacteria and lactic acid bacteria, while inhibiting the proliferation of harmful bacteria such as Escherichia coli and streptococcus. FOS are fermented by beneficial bacteria in the back of the intestinal tract to produce short-chain fatty acids such as lactic acid, acetic acid, propionic acid, butyric acid, and gases such as carbon dioxide and methane. Most of the organic acids can be absorbed, which means that FOS can also indirectly provide some energy to host. Organic acids also protonate the potential toxic ammonia to generate NH 4+, and lactic acid increases the acidity of the cecum, which is conducive to the growth of lactic acid bacteria and bifidobacteria. These bacteria can also use ammonia as a nitrogen source, thereby reducing ammonia levels in the intestinals and blood. Prebiotics such as FOS can also regulate the morphology, structure and function of the intestinal mucosa, such as the height of intestinal villi, the depth of crypts, the thickness of the epithelial layer, and the number of epithelial cells. These intestinal changes can promote the digestion and absorption of nutrients.

FOS is a kind of non-digestible oligosaccharides, which cannot be directly digested and absorbed by animal body, but can be utilized by microorganisms such as Lactobacillus and Bifidobacteria in the intestinal tract, so as to achieve the purpose of regulating the microbial flora in the intestinal tract. Therefore, adding FOS to animal feed can change the intestinal microecology of animals, eliminate pathogenic bacteria in the digestive tract, improve the absorption and utilization of feed nutrients by animals, activate their immune system, and establish a healthy intestinal microbial system.