VEGAMAX-The Use of Probiotics as Feed Additives

1. What are probiotics???

Probiotics?are kind of beneficial microorganisms and can be found in normal animals. They are mainly distributed in digestive tract, respiratory tract and reproductive tract, among which the digestive tract is the most common. Probiotics and harmful bacteria co-exist to form a mutually restricted system, which we call microecosystem. For healthy animals, harmful bacteria are weak bacteria, affected by beneficial bacteria continue to be under inhibition, won’t propagate in large numbers and cause disease. On the contrary, if the body under stress, the inhibition to harmful bacteria will be temporarily lifted. Therefore, harmful bacteria exist with conditional pathogenicity in animals.

The metabolites secreted by probiotics include three categories, the first is digestive substances, such as protease, amylase, cellulase, hemicellulase, pectinase, lipase, etc. They make the energy, protein, crude fiber and other diets digest sufficiently based on the original digestive enzymes in the intestinal tract to reduce the occurrence of accumulated food, indigestion, overfeeding and so on. With the increase of feed utilization rate, the FCR will decrease, and supply cycle will be shortened.

The second is antibacterial substances, including antimicrobial peptides, lysozyme, etc., which can directly inhibit and kill harmful bacteria. It is a kind of non-specific antibacterial effect， which is different from antibiotics. Some manufacturers also specialize in the purification of these metabolites for the study of non-resistant culture.

The third is about nutritional metabolites, including organic acids, vitamins, etc. Organic acids are mainly propionic acid, acetic acid, formic acid, etc., which are suitable for ruminants. These organic acids are absorbed and converted into energy in the body through the gluconeogenesis pathway. Vitamins are mainly vitamin B which are absorbed as coenzymes to participate in body metabolism and promote animal growth and development.

Probiotics can also inhibit the colonization of harmful bacteria in the intestinal tract by occupying space and competing for the structural sites of the host intestinal mucosa and can also inhibit the survival of harmful bacteria by competing for nutrients and oxygen needed by microorganisms.

2. Application background of probiotics: reducing resistance and forbidden resistance

Before 2020, low-dose antibiotics are widely used in livestock and poultry breeding. Antibiotics can not only improve the production performance of livestock and poultry, but also prevent most diseases.

Gastrointestinal (GI) diseases represent one of the main causes of death of young animals taking the second place after viral diseases. GI diseases are primarily associated with disorders of the intestinal biocenosis, and a resistance decrease caused by a weakening of the immune system under conditions of overcrowding of the poultry and livestock within limited areas, technological and feed stresses, and chemical stresses caused by the use of antibacterial drugs and antibiotics. In the most cases, animal and poultry farms use significant amounts of antibiotic drugs for therapeutic and prophylactic purposes. However, a long-term use of antibiotics (especially broad-spectrum ones) results in the development of drug resistance in pathogenic and opportunistic microflora.

With the promulgation of anti-resistance and anti-prohibition policy, finding substitutes for antibiotic feed additives has become the development trend in the future. The application prospect of probiotics as feed additives in agriculture is broad. China has gradually stopped the use of some antibiotics since 2016, officially announced that completely ban on AGP from July 2019, and officially implemented it on July 1, 2020. The process gives Chinese company sufficient preparation time. As of today, it has been 2 years for China’s?feed to be non-antibiotics.

3. How to select probiotics ?

When selecting potential probiotic microorganisms, one should take into account a number of their functional, safety, and technological characteristics. Probiotic bacteria should satisfy the following main requirements: they should be non-pathogenic and non-toxic, possess antagonistic activity against pathogenic and opportunistic microflora, and remain viable both in the gastrointestinal tract (GIT) and during storage in a pure form or as a forage component under industrial conditions.

The composition of the gut microbiota plays an important role in the health of animals and increasing the population of?bacteria in genus Bifidobacterium,?Lactobacilli, and Eubacteria in the gut may improve the health of the animals and decrease the risk of diseases. Growth of these bacteria increases the concentration of lactic and acetic acid, which will reduce the pH in the intestine and increase fermentation with a subsequent increase in the concentration of SCFA and a reduced concentration of pathogenic bacteria.

The aim of these changes is to improve the animals' ability to prevent pathogenic bacteria from colonizing the intestinal system, which often is accomplished via an improved immunological response to pathogens. This also can be accomplished via mechanisms that prevent the pathogens from adhering to intestinal mucosa or releasing toxins, and thus, reduce the damaging effects of the pathogens on the host.

?

4. The species of probiotics commonly used as feed additives

Bacillus

There are many kinds of bacteria in the genus?Bacillus,?the common ones are Bacillus polymyxa, Bacillus subtilis, Bacillus licheniformis,?Bacillus subtilis, Bacillus coagulans?and so on.?Bacillus bacteria synthesize a number of antimicrobial compounds characterized by a selective activity against pathogens, but not beneficial microbiota such antimicrobial metabolites have different mechanisms of action. Bacillar metabolites can affect the lipid bilayer of a plasmatic membrane.?Using electrostatic interactions, this compound is attached to the phospholipid layer of the plasmatic membrane affecting membrane permeability and causing cell death.

Bacillus subtilis?is heat?and acid?resistant,?and can form biofilms in small intestine. This?property ensures its stability and ability to be widely used.?Bacillus subtilis?has no drug resistance, hemolysis and cytotoxicity, and can help animals absorb more nutrients by protecting digestive tract barrier and optimizing intestinal flora, especially for the absorption of calcium, phosphorus and other mineral elements. Therefore, Bacillus subtilis?can prevent osteoporosis. Along with antimicrobial properties,?Bacillus subtilis?produces enzymes utilizing the products of putrefactive decay of tissues, recovers populations of microorganisms composing the intestine normoflora, and synthesizes amino acids, vitamins, and immunoactive compounds.

Bacillus coagulans?has the common characteristics of?Bacteriaceae?and Lactobacillaceae. Its spores have certain antibacterial activity and stable properties, and can be activated in acidic environment.?After entering the digestive tract, it is activated by the stimulation of gastric acid?and then adheres and increases in the intestinal tract.?The spores can adapt to hypoxic environment, play a similar role as lactic acid bacteria in the intestinal tract for a long time. It also?can secrete lectin that lactic acid bacteria don’t have, which has a good effect on the inhibition of intestinal microorganisms.?However, because of the difficulty to adhere in?the intestinal tract, long-term administration is needed to maintain the?effect?of Bacillus coagulans.

Bacillus licheniformis?produces a number of enzymes involved into food digestion and toxin neutralization and stimulates interferon production that results in a suppression of the growth and propagation of pathogenic microorganisms and viruses facilitating the normalization of intestine microflora.

Clostridium butyricum

Clostridium butyricum?has been widely studied by scholars all over the world since it was isolated from pigs’?intestine in 1880.?This is a gram-positive anaerobe that can produce spores and is a symbiotic flora of the environment, human and animals’?intestine. Clostridium butyricum?can significantly improve the growth performance of broilers as a feed additive. Feeding to piglets can also improve their growth performance, increase feed intake, improve feed utilization rate, and alleviate the diarrhea that often occurs in weaned piglets. This is mainly because?Clostridium butyricum?has a certain resistance to high temperature and pressure, and can better adapt to the environment in the gastrointestinal tract of animals. Based on these characteristics,?Clostridium butyricum?is a kind of product which can replace antibiotics as a feed additive.

Lactic acid bacteria

As one of the normal flora in animals, lactic acid bacteria can reduce the inflammatory response of pathogens and regulate the expression of immune cytokines.?Lactic acid bacteria include Lactobacillus, Bifidobacterium?and Gram-positive cocci.?Lactobacillus, which is widely uesd, includes?Lactobacillus plantarum, Lactobacillus acidophilus?and so on. Lactobacillus plantarum?has a strong ability to ferment sugar. After fermentation, it can produce a large amount of lactic acid and has no other metabolites. There is a close relationship between intestinal microorganisms and intestinal immune function. It has been proved that?Lactobacillus plantarum?can promote the increase of beneficial bacteria in animals’?intestine and reduce the number of pathogens. There is a close relationship between intestinal microorganisms and intestinal immune function. Lactobacillus acidophilus?can regulate immune response in?vivo?and in?vitro. It can produce bacteriocin compounds, regulate intestinal pH value, and regulate intestinal flora through competitive rejection. In addition, Lactobacillus acidophilus?can directly ferment nutrients in the intestinal tract, produce growth-promoting factors, stimulate peristalsis of the small intestine and improve feed utilization.

Yeast?

Yeast is a single-celled fungus, which is rich in enzymes, amino acids and vitamins.?Because of the?fast reproduction speed and short growth cycle,?Yeast is commonly used?as a?additive in food processing.?The addition of yeast in?feed can promote the fermentation of feed and the fermented feed has higher nutritional value.?It also?can be used as growth hormone to promote the growth and development of animals.?Yeast can not only be used to ferment feed alone, but also cooperate with other probiotics to make compound probiotic preparation. This can improve the quantity of beneficial products in the feed and improve the feeding value of the feed. The addition of yeast to agricultural and sideline products can not only improve the palatability of feed, but also alleviate the breeding pressure in remote areas with feed shortage and promote the development of animal husbandry.

?

5. The effect of probiotics depends on:

（1）Intestinal adaptability?

The key segment of intestinal flora regulation is the hindgut segment. ?This area is anoxic or microaerobic.

（2）Strain capacity??

The role of probiotics depends on the strain, not the strain.

（3）The ability to produce metabolites.

（4）Scientific?combination?

Only the scientific combination can exert the synergistic effect.

Can the combination cover the whole digestive tract?

Is the combination a product synergy?

Is the combination repeated?

Contact us:

Website: https://www.vegapharma.com/index/bilepro/index.html

Email: [email protected]