The term probiotic is derived from the Greek word (Probios) and unlike antibiotic which means anti-biotic, it literally means to support life.
When it comes to the use of live microbial products in animal feed and poultry feed, the goal is to affect the microbial activity in the digestive system of the animal, or in other words, to improve the health and growth of the animal, the favorable and benign activities of microbes are stabilized and strengthened, so that with The use of beneficial microorganisms can not only improve growth and conversion rate in livestock and poultry, but also reduce the anti-growth effects of harmful microorganisms as well as the occurrence of diseases.
During the past years, there has been a lot of enthusiasm among researchers, researchers and also producers in the field of live microbial cultures to increase production in livestock and poultry.
In general, the microflora of the digestive tract of animals plays an important role in livestock and poultry production, and in addition, it has direct and positive effects on the formation and absorption of vitamins, and these microorganisms are responsible for protecting the body against infection.
Microorganisms forming the microflora of the digestive tracts of domestic animals can be divided into two categories:
The first category are useful or desirable microbes that accumulate on the surface of the intestine and have a symbiotic relationship with the host animal.
The second category is undesirable microbes that are potentially pathogenic.
In normal conditions, beneficial microorganisms are dominant in terms of the population, and their presence is necessary for the animal’s physiological actions, including helping to digest food and competing with pathogenic microorganisms.
Animals that are born sterile (germ free) and raised in a germ-free environment have a weaker immune system. In these animals, the susceptibility to bacterial infections is much higher, because pathogenic bacteria do not have to deal with the natural microflora.
Most commercial products containing microbes are labeled as probiotics (vital precursors). In recent years, these new compounds have been used as an additive in livestock and poultry feed.
The use of probiotics, unlike antibiotics, requires the addition of live microorganisms to feed rather than their products. Therefore, probiotics are not specific chemical molecules and it is difficult to determine their amount and mode of action.
Microbes that are used as probiotics in livestock and poultry feed are usually part of the intestinal microflora. The purpose of using these microbes in the diet is to overcome their population over the microbial populations harmful to the digestive system.
Lactobacilli, streptococci, probiotics, bifidobacteria and some bacilli can be mentioned among these microbes.
Salmonella and colibacilli are harmful microbes to the digestive system. The predominance of beneficial microbes in the digestive system over harmful microbes increases growth, improves the food conversion ratio, and increases nitrogen and calcium retention.
On the other hand, these microbes reduce plasma cholesterol and, as a result, reduce egg cholesterol.
Definition of probiotics
The term probiotic is derived from the Greek word (Probios) and unlike antibiotic which means anti-biotic, it literally means to support life.
This term is used to describe live microbial additives in food that can have a positive effect on improving animal performance and increasing the growth rate of livestock and poultry by creating a microbial balance in the intestinal flora population and preventing gastrointestinal infections.
With this definition, probiotics can be distinguished from antibiotics, because these compounds are living organisms.
One of the most important advantages of these products is that they do not remain in the body tissues after entering the digestive system of livestock and poultry, and unlike antibiotics, they do not create any microbial resistance after consumption.
History of probiotics
In 1907, Metchnikoff observed in the villages of Bulgaria that eating a kind of yogurt fermented from milk increases the life span and preserves the health of the villagers. His study on this yogurt showed that it contains significant amounts of Bacillus Bulgaricus and Streptococcus Thermophilus.
In 1976, an American researcher named Parker raised the issue of probiotics. He introduced probiotics from organisms and substances that participate in creating intestinal microbial balance.
What Professor Parker meant by the word balance was actually the beneficial ratio between lactobacilli and other members of the intestinal microflora. He considered lactobacilli as organisms that can strengthen the effect of beneficial and benign intestinal microbes as a barrier against the invasion of pathogens such as Escherichia coli (E. Coli).
Krueger reported in 1977 that Lactobacillus cultures in Leghorn hens increased egg production, improved feed conversion and reduced losses in laying flocks.
In 1992, Cox used probiotics in eggs to prevent salmonella infection after birth and got completely positive results. Crawford (Crawford) in 1979 showed in broiler chickens, the groups that were fed with probiotics were in a better condition than the control chickens in terms of weight, feed conversion ratio and losses.
In 1989, Fuller was able to inhibit Escherichia coli by preparing an acidic culture medium. According to his report, the inhibition of Escherichia coli in the poultry layer depends on the presence of lactobacilli.
Probiotic properties
In general, a probiotic should have the following characteristics:
Not pathogenic.
Gram positive.
Be resistant to acid.
Have a specific strain.
Be resistant to the secreted and excreted substances of Escherichia coli.
Be resistant to bile. Because bile salts reduce the surface tension and emulsify fats in the intestine, on the other hand, the bacterial cell wall contains fat and fatty acids, so probiotic microorganisms must be resistant to bile.
contain at least 3 x 106 cfu/gr. (CFU = Colony forming unit)
be alive and stable.
Benefits of probiotics
1. Stimulation of lymphocytes
2. Absorption of antigens released from pathogenic bacteria
3. Connecting to the intestinal epithelium and preventing the connection and colonization of pathogenic bacteria
4. Increase the activity of macrophages up to 4 times
5. Increasing interferons, IgM, IgG and building a barrier against invading pathogens
6. Improving the balance of intestinal microbial flora
7. Reducing the incidence of diarrhea
8. Reducing casualties
9. Improving food hygiene (especially lactobacillus)
10. Reducing plasma cholesterol and as a result reducing egg cholesterol
11. Positive effect on poultry growth and egg production
12. Making poultry resistant to stress
13. Preventing cancers, especially gastrointestinal cancers
14. Treatment of constipation
