The normal microflora of the animal's body is brief. Microflora of air and water. Quantitative and qualitative determination of the microflora of air and water. The role of normal microflora

V recent times interest in the indigenous (own) microflora of agricultural and domestic animals and methods of its correction has significantly increased. The question of the possibility of the existence of animals and humans in the absence of microorganisms was first raised by Louis Pasteur (quoted in 10). According to modern concepts, a natural habitat requires a symbiosis of a macroorganism with a microorganism inhabiting it. Microbial animals (and plants) can live and develop only under artificial isolation (sterile environment). The normal microflora of animals and humans constantly persists in the host's organism and interacts with him according to the principle of symbiosis. The indigenous flora is represented by microbiocenoses (certain communities of microorganisms) that form in natural niches (biotopes) of the physiological systems of the macroorganism (digestive tract, respiratory and urogenital apparatus, skin, etc.) in contact with external environment... In any microbiocenosis, a distinction is made between the characteristic of a given species (obligate, resident) and random (optional, temporary, transient) microflora. Each of the biotopes forms its own, different from others, conditions for the existence and interaction of microorganisms inhabiting them. Therefore, the species and quantitative composition of flora in different biocenoses have significant differences. In this regard, there are concepts such as the microecology of the intestines, skin, genitals, upper respiratory tract, oral cavity, etc. A living organism contains a huge number of cells of symbiont microorganisms (up to 1014). Their species diversity (over 400 species) ensures the participation of normal microflora in a wide variety of physiological functions of a macroorganism (13, 14). One of the most important functions of normal microflora is to provide colonization resistance (CR) in relation to both foreign microorganisms that penetrate into the host's body, and to restrict the reproduction of its individual representatives outside their habitats. With a decrease in CR, the balance of the qualitative and quantitative composition of the indigenous flora is disturbed. Due to an increase in the growth of individual populations of microorganisms, the latter colonize the skin and mucous membranes of the macroorganism, and also note the expansion of the distribution area of representatives of the opportunistic (conditionally pathogenic) microflora, including aerobes and anaerobes, and their translocation into internal organs. This leads to purulent-inflammatory processes, septicemia. The transmission of antibiotic resistance and pathogenicity factors between bacterial communities is enhanced (1, 8, 16). The most complex microbiocenoses of mammals are the microflora of the colon, mouth and nasopharynx. The qualitative and quantitative composition of the microflora of the skin surface, as well as the mucous membranes of the nasal cavity, genitals, etc. more meager. Therefore, the indigenous intestinal microflora has a significant effect on the state of microbiocenoses in other biotopes of a living organism. Normal flora composition gastrointestinal tract a healthy adult dog (Table 1) is stable and in the absence of significant changes in the conditions of feeding, maintenance, stressful situations, as well as diseases with the use of pharmacological preparations, fluctuates insignificantly. Due to the high acidity, the microbiocenosis of the stomach is rather scarce. Microorganisms capable of maintaining their vital activity in an acidic environment and in the presence of pepsin (acidophilus bacillus and other lactobacilli, enterococci, fungi, bacilli, sarcins) are localized mainly in its pyloric part. The specific number of microorganisms in the duodenum and jejunum ranges from 102-105 bacteria per 1 g of their contents. The inhibition of their growth in this part of the thin intestine is provided due to more acidic environment, which is supported by the intake of chyme (stomach contents), and the release bile acids... Active peristalsis, secretory immunoglobulins (IgA, IgE), and enzymes directly participate in the regulation of the number of microorganisms. The main inhabitants - lactobacilli, enterococci, enterobacteria, steptococci, in their quantitative representation are slightly inferior to bifidobacteria, sometimes candida are found. A similar situation is observed in the cranial part of the ileum, while in the caudal microbiocenosis is much more diverse and often includes species that predominantly live in the large intestine (bacteroids, clostridia, eubacteria, fusobacteria, etc.). The specific content of microorganisms in this area can reach 107 per 1 g of intestinal contents. It should be said that the microbiosenosinduced flora of the large intestine in comparison with the small intestine significantly predominates both qualitatively and quantitatively. In addition to those mentioned in Table 1, there are almost always representatives of veyolonella, peptococci, peptostreptococci, actinomycetes, pseudomonas, alkaligenes and other genera (11). As we move to the rectum, the specific content of bacteria grows (1010-1012 microbial cells in 1 g of content). Depending on the moisture content of the faeces, the percentage of bacterial mass in relation to the total weight of the test material fluctuates within 15-30%. This article primarily proposes the results of a study of intestinal microecology in dogs aged 2-7 years, where Special attention were given normal microflora. In the next issues, we plan to present materials on the age dynamics of the indigenous intestinal flora, the reasons for the development of dysbacteriosis (decrease in CR) and methods of their correction will also be considered. The obtained results show that the basis of normal intestinal microflora of barren dogs, as in other animals, is formed by non-spore-forming obligate anaerobic microorganisms. The ratio of representatives of the anaerobic-aerobic intestinal flora in the body is approximately 1000: 1, respectively. The most important representatives of the resident flora of the gastrointestinal tract are bifidobacteria and lactobacilli, bacteroids, enterococci, Escherichia, yeast-like fungi (9). Bifidobacteria Most of the intestinal normal flora (from 60 to 90% or more) in healthy dogs, as well as in other monogastric animals, are bifidobacteria (Fig. 1). Normally, from 1 g of the content of the large intestine of dogs (depending on age, type of feeding, etc.) they were sown up to 1012. Veterinarians should be paid attention to the fact that microscopic examination of feces using special methods of staining smears can only give an approximate idea of the ratio of the main groups populations of microorganisms (presence of cocci, gram-positive and gram-negative bacteria, fungi, etc.). The presence or absence of bifidoflora cannot be established by this method, because it has morphological similarities with a number of other bacteria - obligate intestinal microorganisms (Appendix 1). Determination of the quantitative content of bifidoflora is carried out by inoculation of sequential tenfold dilutions of the test material on elective (special) semi-liquid nutrient media, which are poured in a high (not less than two-thirds of the tube height) column and regenerated (warmed up) before sowing. The material undergoing bacteriological analysis is carefully introduced into the lower part of the tube, the contents of which are slightly stirred, while observing the conditions of anaerobiosis, and then incubated at an optimum temperature for 1 to 3 days. This kind of research requires high qualifications and practical skills of a bacteriologist. Considering the dominant position of bifidoflora in the intestines of healthy individuals, as well as data from clinical and microbiological studies, many authors have come to the conclusion that representatives of the genus of bifidobacteria are the main taxonomic group of microflora of the gastrointestinal tract, which is an indicator of health (4). Indeed, with a decrease in KR, bifidoflora is the first to disappear from the gastrointestinal tract. The predominance of these microorganisms in the intestine, as a rule, prevents the reproduction of pathogenic and opportunistic bacteria, normalizing the microbiocenosis as a whole. The antagonistic activity of bifidobacteria to pathogens related to canterobacteria (Escherichia, Klebsiella, Salmonella, Proteus, Shigella, etc.), cocci (Streptococcus, Staphylococcus), vibrio, campylobacter, the process of clostridium organisms, and other enzymes is provided by the process of clostridium organisms, and other lactate, production of volatile fatty acids (VFA), lysozyme-like and other substances with antibacterial activity, as well as the ability to suppress toxin formation or destroy toxins of pathogenic bacteria, etc. Particularly should be emphasized their participation in symbiosis with a macroorganism at the level of parietal digestion, which is determined by well-pronounced adhesive properties. This is one of the main elements of competitiveness in the development of the food niche in relation to other representatives of the indigenous flora and pathogens. Bifidobacteria are directly involved in the regulation of the immune functions of a macroorganism. They stimulate cell proliferation lymphoid tissue, enhance the phagocytic activity of macrophages, monocytes and granulocytes, enhance specific humoral immunity, cytokine synthesis (production of interferon gamma, JL-6, TNF, ALPHA), and also stimulate immune mechanisms at the cell level, including antitumor protection (7, 15). Like other representatives of the indigenous flora, bifidobacteria are capable of causing deconjugation of bile acids. They are also actively involved in water-salt, protein, fat, nucleotide, vitamin metabolism, maintaining pH and anaerobiosis in the intestine. They synthesize amino acids such as lysine, arginine, valine, methionine, leucine, tyrosine, and glutamic acid. For a share essential amino acids accounts for about 40% of their total. Intracellularly, bifidobacteria accumulate vitamins B1, B2, B6, B12, C, nicotinic, folic acid and biotin, and also produce B6, B12 and folic acid... With a deficiency of representatives of this genus, the synthesis of endogenous formation of vitamin K decreases, which leads to a violation of the processes of blood coagulation. The brief description of bifidobacteria indicates that they, as one of the varieties of the normal flora of a macroorganism, dominate not only quantitatively, but also qualitatively (physiological). In our species identification of bifidobacteria isolated from feces of dogs, it was shown that the species B.adolescentis was predominant (41.7% of strains), the second most abundant was the species B.globosum (16.7%), the third was B. termophilum (8, 3%). In no case was it possible to isolate from dogs bifidobacteria of the species B. bifidum, characteristic of the human intestine and used for the manufacture of probiotic preparations in humanitarian medicine. Lactobacilli The second largest group of resident flora of the gastrointestinal tract of dogs are lactic acid bacteria, representatives of the genus Lactobacterium (Appendix 2). According to our research, the number of lactobacilli in healthy dogs is 106-109 / g of the contents of the large intestine (Fig. 1). Decrease in KR (dysbacteriosis) lactobacilli are sown in much smaller amounts or they cannot be detected at all (Fig. 2). Lactic acid bacteria as obligate representatives of the gastrointestinal tract take an active part in the processes occurring in it. They ferment a large amount of carbohydrates and alcohols, some representatives of this genus cause hydrolysis of starch and synthesize proteins. The antagonistic activity of lactic acid bacteria in relation to putrefactive, pathogenic and conditionally pathogenic microflora is due to their ability to synthesize numerous antibiotic substances. Some of them are low molecular weight proteins. They were classified as bacteriocins, similar in their mechanism of action to antibiotics, but differing from them in low activity against closely related species of microorganisms (Appendix 3). Characteristic physical and chemical properties bacteriocins of acidophilic bacteria allowed to combine them under the term "Lactacin B". In addition, lactobacilli produce antimicrobial substances called lantabiotics. They are less sensitive to the action of amylases and proteinases and contain amino acids that are usually not present in bacteriocins. In addition to bacteriocins and lantabiotics, lactobacilli synthesize unidentified substances with a bacteriocin-like effect. These low molecular weight organic compounds non-protein nature show their activity in the presence of acid or hydrogen peroxide. They inhibit the growth and development of pseudomanadas, salmonella, shigella, streptococci, staphylococci, as well as anaerobic bacteria, including clostridia, bifidobacteria and bacteroids. One of the most important metabolic products of lactic acid bacteria is hydrogen peroxide. The ability to produce it is determined by a genetically determined trait and does not depend on the main environment and contact with oxygen. The inhibitory effect of hydrogen peroxide in the intestine is more important for the control of the number of representatives of the aerobic flora than the effect of organic acids produced by it. The bactericidal effect of hydrogen peroxide is associated with its strong oxidative effect on bacterial cells and the destruction of the basic molecular structure of cellular proteins. Lactobacilli play an important role in the development of immunity in newborns with low activity of cellular and humoral immunity and low phagocytic activity of mononuclear macrophages. An increase in the phagocytic activity of macrophages, the capture and catabolism of antigens by them is observed with oral, subcutaneous and intraperitoneal administration of live lactobacilli, supernatants, killed cultures or fragments of their walls. In vitro and in vivo, lactic acid bacteria stimulate the production of interferons and interleukins (3, 7). In addition to the listed properties, providing an immunostimulating and antagonistic effect against pathogens, lactobacilli have other important physiological functions. They are actively involved in the metabolism of carbohydrates, proteins, lipids, nucleic acids... They, as well as bifidobacteria, play an important role in the regulation of water-salt metabolism, maintaining pH and anaerobiosis in the intestine, deconjugation of bile acids, synthesis of vitamins, amines and other biologically active compounds. Most of the strains of lactobacilli we studied, isolated from dog feces, were classified as L. acidophilum (56%), the second most abundant was L. plantarum (16%), and the third - L. helveticum (12%). Escherichia These are saprophytes, which are normally part of the resident intestinal flora. They are located randomly and evenly throughout the intestinal cavity, localized mainly in the lumen and only partially adjoin the epithelium of its villi. Just like bifidobacteria and lactobacilli, Escherichia actively participate in enzymatic processes in the intestine, while forming organic acids, vitamins and other biological active substances... In 1905, H. Conrad found that as a result of the vital activity of Escherichia, bactericidal substances accumulate in the nutrient medium, preventing the growth of other bacteria. Currently, it is known that Escherichia produce both in vitro and in vivo up to 24 types of such substances, called colicins. Perhaps the intestinal flora should not be called saprophytic, but opportunistic, since in comparison with other representatives belonging to this category of microorganisms, it is the most aggressive: Escherichia are among the first to populate the organism after birth and are more often than others found in the blood of animals with a decrease in natural immunity, for example, after irradiation. So, according to the authors (2, 5), more than in 50% of cases they are the cause of septicemia in irradiated animals. It should be remembered that a huge number of Escherichia are pathogens with a constantly expressed high virulence (Appendix 4). In different parts of the intestines of healthy dogs, the number of Escherichia ranges from 102 to 109 colony-forming units per 1 g of the test material. Own studies carried out on healthy dogs show that the number of sherichia ranges from 106-109 per gram of feces. Bacteroids In the composition of the normal microflora of the gastrointestinal tract, as well as the oral cavity, upper respiratory tract, genitourinary organs, includes bacteroids. The genus Bacteroides includes more than 20 species, most of which are excreted from the human body and animals. In an acidic environment, bacteroids exhibit antagonistic activity against Salmonella, Escherichia, and other microorganisms and, apparently, play a significant role in the body's resistance to infections. However, the research results recent years testify to their participation in the etiology of many pathological processes: enteritis, necrotic hepatitis, peritonitis, meningitis, etc. The study of the pathogenicity of representatives of this genus in animals indicates their synergism in the development of infectious processes, which is noted in relation to borrelia, mycoplasma, streptococci, staphylococci, pasteurella, and in humans - cholera vibrio (6). In 1 g of the contents of the large intestine of healthy dogs, their number fluctuates within 107-1010. Enterococci Fecal streptococci or enterococci are widespread in nature. They are found in the intestines and faeces of humans and animals, as well as in soil and water. Enterococci are obligate representatives of the normal microflora of the gastrointestinal tract and some of them (mainly Ent. Faecium) are included in the composition of probiotic preparations to normalize the intestinal microflora. The antagonistic functions of these microorganisms are mainly associated with their acid-forming properties and the ability to produce bacteriocins. At the same time, enterococci are facultative anaerobic opportunistic microorganisms that can cause gastroenteritis, pneumonia, mastitis, endocarditis, meningitis, septicemia and other diseases in animals and humans. As is characteristic of all opportunistic microorganisms, their negative effect is manifested in individuals with a decrease in overall resistance. The content of representatives of this genus of microorganisms in healthy dogs is 104-108 / g of feces (own research). Clostridia Up to 35 species of Clostridia are found in the body of animals and humans. Quantitative indicator certain types(Cl.clostridiforme, Cl.innocuum, Cl.ramosum) can reach 108-109 / g of feces (11). According to our own research, the frequency of isolation of clostridia from the intestines of dogs fluctuated within 75-100% of cases. Their specific content in various departments ranged from 0 to 104 / g of the test material. A characteristic feature of clostridia is their ability to saprophytic existence in the soil and gastrointestinal tract of humans and animals. The role of representatives of this genus for a macroorganism (excluding pathogenic species) has not been sufficiently studied. There is literature data indicating the synthesis of clostridium vitamins: nicotinic, folic, pantothenic acid and riboflavin (12). Therefore, it is natural to assume that Clostridia are also involved in the maintenance of intestinal hormobiosis of their host. Moreover, some authors believe that clostridia, especially those species, the number of which can reach large values, are the most ancient regulatory system of human and animal microecology, providing homeostatic relationships between the host and its microflora. Fungi of the genus Candida Yeast-like fungi of the genus Candida constitute an independent genus and have more than 80 species. They are part of the normal flora that populates the mucous membranes of the respiratory apparatus and gastrointestinal tract, as well as the genitals and skin. From feces of healthy dogs, we sowed them in quantities up to 103, rarely - 104 / g. Fungi of the genus Candida are also conditionally pathogenic microorganisms, and all factors that reduce the general or colonization resistance of the macroorganism and depressive non-specific immune defense, create conditions for the activation of their growth and development of a specific disease - candidiasis. In experiments on monkeys and dogs, it was shown that these microorganisms can enter the host's body through the mucous membranes of the intestinal tract and enter the bloodstream. Endotoxin, which causes damage to parenchymal organs, is essential in the pathogenesis of the disease. The groups of microorganisms listed above make up the bulk of the resident microflora, more or less studied for the gastrointestinal tract of animals. It should be noted that only bifidobacteria and lactobacilli are microorganisms whose participation in pathological processes(both direct and indirect) has not been established to date. In addition to the resident microflora in the gastrointestinal tract, there are sporadically other microorganisms called transient, which are most often sown in diseases of the gastrointestinal tract of animals, although among them there are saprophytic types of microbes. First of all, these are Klebsiella, Pseudomonas, Proteus, Staphylococcus, Spirochetes, Citrobacters, Enterobacteria, Molds and others. The quantitative diversity of the resident microflora of dogs, the numerical ratio in the microbiocenosis of a particular biotope of the resident and transient microflora is mainly influenced by age, type of feeding, and various environmental factors, including the use of drugs. While representatives of normal microflora predominate in microbiocenoses, the CD and the health of the macroorganism as a whole are preserved. If external influences(chemotherapy drugs, pesticides and other poisons, stresses, virulent microorganisms, etc.) exceed in intensity compensatory mechanisms ecological system"A macroorganism is its normal microflora", then the transient microflora begins to predominate in microbiocenoses, which leads to the development of local infectious processes, or even generalized infection and other complications. Thus, it is obvious that the animal organism and the microflora inhabiting it are interdependent and coexisting parts. unified system... From an ecological point of view, the interaction between macro- and microorganisms is a special case of the symbiosis, which is universally widespread in the living world, with its various forms(commensalism, mutualism, parasitism, predation, etc.). Based on the above, it follows that the interaction between the normal microflora and the host organism is mainly carried out at the level of mutualism. Intestinal microorganisms, being part of the normal flora, are at the same time a complex self-regulating open system where their different populations have diverse relationships both at the level of their communities and with the host organism. The most noticeable role is played by their competitive and antagonistic properties, which, in general, determines normal functioning a unified ecological system: an animal organism - its environment

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MINISTRY OF AGRICULTURE OF THE RUSSIAN FEDERATION

FGBOU VPO "URAL STATE

AGRARIAN UNIVERSITY "

ESSAY

on discipline: "Microbiology of meat"

on the topic "Microflora of the animal body"

Ekaterinburg

WITHobsession

Introduction

1. Definitions, terminology

2. The species composition and quantitative characteristics of the microflora of the most important areas of the animal's body

3. Distribution of microorganisms in the parts of the gastrointestinal tract

4. Differences in the microflora of the body of different species of animals

5. Normal microflora of the body and pathogenic microorganisms

6. Morphofunctional role and metabolic function of the body's auto microflora

Bibliography

Vconducting

The microflora of the organism of mammals, including agricultural, domestic animals and humans, began to be studied together with the development of microbiology as a science, with the advent of the great discoveries of L. Pasteur, R. Koch, II Mechnikov, their students and collaborators. So, in 1885, T. Escherich isolated from the feces of children an obligatory representative of the intestinal microflora - E. coli, which is found in almost all mammals, birds, fish, reptiles, amphibians, insects, etc. After 7 years, the first data on the value Escherichia coli for vital functions, health of the macroorganism. S.O. Jensen (1893) established that different types and E. coli strains can be both pathogenic for animals (cause septic disease and diarrhea in calves), and non-pathogenic, that is, completely harmless and even useful inhabitants of the intestines of animals and humans. In 1900, G. Tissier discovered bifibacteria and obligatory representatives of the normal intestinal microflora of the body in the feces of newborns during all periods of his life. Lactic acid sticks (L. acidophilus) were isolated by Moreau in 1900.

1. Odefinitions, terminology

Normal microflora is an open biocenosis of microorganisms found in healthy people and animals (V.G. Petrovskaya, O. P. Marko, 1976). This biocenosis should be characteristic of a perfectly healthy organism; it is physiological, that is, it contributes to the maintenance of the healthy status of the macroorganism, the correct administration of its normal physiological functions... The whole microflora of the animal's body can also be called auto microflora (according to the meaning of the word "auto"), that is, the microflora of any composition (OV Chakhava, 1982) of a given organism in health and disease.

The normal microflora associated only with the healthy status of the body is divided by a number of authors into two parts:

1. an obligate, permanent part that has developed in phylogeny and ontogeny in the process of evolution, which is also called indigenous (i.e., local), autochthonous (indigenous), resident, etc.

2. optional, or transitory.

The auto microflora can periodically include pathogenic microorganisms accidentally penetrating into the macroorganism.

Body microflora composition

2. Vid composition and quantitative characteristics of the microflora of the most important areas of the animal's body

As a rule, tens and hundreds of species of various microorganisms are associated with the animal organism. They, as V.G.Petrovskaya and O.P. Marko write (1976), are obligatory for the organism as a whole. Many types of microorganisms are found in many areas of the body, changing only quantitatively. Quantitative variations are possible in the same microflora, depending on the species of mammals. The majority of animals are characterized by general averaged indicators for a number of areas of their body. For example, for the distal, lower parts of the gastrointestinal tract, the following microbial groups are characteristic, found in the contents of the intestine or feces (Table 1).

Table 1. Microflora of the lower gastrointestinal tract

	The number of microbes in 1 g of material from the intestine
Bifidobacteria	107 - 109 (up to 1010)
Bacteroids	1010 (up to 1011)
Peptococci
Peptostreptococci
Coprococci
Ruminococci
Fusobacteria
Eubactria
Clostridia
Wylonella
Anaerobic gram-negative cocci of the genus Megasphaera
Various groups of spiral-convoluted (curved) bacteria, spirochetes
Lactobacillus
Esherichia
Enterococci
More transiently can be presented:
Other representatives of enterobacteria (Klebsiella, Proteus, Citrobacter, Enterobacter, etc.)
Pseudomonas
Staphylococci
Other streptococci
Diphtheroids
Aerobic bacilli
Mushrooms, actinomycetes

At the top of the table. 1. shows only obligate anaerobic microorganisms - representatives of the intestinal flora. It has now been established that the share of strictly anaerobic species in the intestine accounts for 95-99%, and all aerobic and facultatively anaerobic species make up the remaining 1-5%. microflora body animal organism

Despite the fact that tens and hundreds (up to 400) of known types of microorganisms live in the intestine, completely unknown microorganisms may also exist there.For example, in the cecum and colon of some rodents in recent decades, the presence of so-called filamentous segmented bacteria has been established, which are very are intimately associated with the surface (glycocalyx, brush border) of epithelial cells of the intestinal mucosa. The thinned end of these long, filamentous bacteria is deepened between the microvilli of the brush border of epithelial cells and, apparently, is fixed there so that it presses the cell membranes. There can be so many of these bacteria that they, like grass, cover the surface of the mucous membrane. These are also strict anaerobes (obligate representatives of the intestinal microflora of rodents), species useful for the body, in many respects normalizing the functions of the intestines. However, these bacteria were detected only by bacterioscopic methods (using scanning electron microscopy of sections of the intestinal wall). Filamentous bacteria do not grow on nutrient media known to us, they can only survive on dense agar media for no more than one week) J. P. Koopman et. al., 1984).

3. Rdistribution of microorganisms by sections of the gastrointestinal tract

Due to the high acidity gastric juice the stomach contains a small amount of microorganisms; it is mainly acid-resistant microflora - lactobacilli, streptococci, yeast, sardines, etc. The number of microbes there is 10 3 / g of content.

Microflora of duodenum and jejunum

There are microorganisms everywhere in the intestines. If they were not in any department, then there would be no peritonitis of microbial etiology when the intestine is injured. Only in the proximal areas of the small intestine there are fewer types of microflora than in the large one. These are lactobacilli, enterococci, sardines, mushrooms, in the lower parts of the increase in the number of bifidobacteria, colibacilli... Quantitatively, this microflora may differ in different individuals. Possible minimum degree of contamination (10 1 - 10 3 / g content), and significant - 10 3 - 10 4 / g The number and composition of the microflora of the large intestine are presented in table 1.

Skin microflora

The main representatives of skin microflora are diphtherois (corynebacteria, propionic bacteria), mold fungi, yeast, spore aerobic bacilli (bacilli), staphylococci (S. Epidermidis predominates, but S. Aureus is present in small amounts on healthy skin) ).

Respiratory tract microflora

On the mucous membranes of the respiratory tract, the most microorganisms are in the nasopharynx, behind the larynx, their number is much less, even less in the large bronchi, and in the depths of the lungs healthy body there is no microflora at all.

In the nasal passages there are diphtheroids, primarily corynebacteria, persistent staphylococci (resident S. epi dermidis), Neisseria hemophilic bacteria, streptococci (alpha hemolytic); in the nasopharynx - corynebacteria, streptococci (S. mitts, S. salivarius, etc.), staphylococci, neisseoia, vailonella, hemophilic bacteria, more commonly enterobacteria, bacteroids, fungi, enterococci, lactobacilli, aerobic bacteria B. subtil is, etc.

The microflora of the deep-lying parts of the respiratory tract has been studied less (A - Halperin - Scottetal., 1982). In humans, this is due to the difficulty of obtaining material. In animals, the material is more accessible for research (you can use killed animals). We studied the microflora of the middle respiratory tract in healthy pigs, including their miniature (laboratory) variety; the results are presented in table. 2.

Table 2. Microflora of the mucous membrane of the trachea and large bronchi of healthy pigs

The first four representatives were constantly detected (100%), less resident (1 / 2--1 / 3 cases) were identified: lactobacilli (10 2 --10 3), Escherichia coli (10 2 --11 3), mold fungi (10 2 --10 4), yeast. Other authors noted the transient carriage of Proteus, Pseudomonas aeruginosa, Clostridia, representatives of aerobic bacilli. In the same plan, we once identified Bacteroides melaninoge - nicus.

Microflora of childbirthx ways of mammals

Recent studies, mainly by foreign authors (Boyd, 1987; A. V. Onderdonketal., 1986; J. M. Milleretal., 1986; A. N. Masfarietal., 1986; H. Knotheua. 1987), have shown that The microflora that colonizes (that is, populates) the mucous membranes of the birth canal is very diverse and rich in species. The components of normal microflora are widely represented, and there are many strictly anaerobic microorganisms in its composition (Table 3).

Table 3. Microflora of the birth canal (vagina, cervix)

Name of microbial groups (genera or species)	Frequency of occurrence,%
Obligatory anaerobic microorganisms:
Bacteroids
Bifidobacteria
Peptococci, peptostreptococci
Wylonella
Eubacteria
Clostridia
Optional anaerobic and aerobic microorganisms:
Lactobacillus
E. coli and other enterobacteria
Corynebacteria
Staphylococci
Streptococci

If we compare the microbial species of the birth canal with the microflora of other areas of the body, we find that the microflora of the birth canal of the mother is similar in this respect to the main groups of microbial inhabitants of the body. of the future young organism, that is, obligate representatives of its normal microflora, the animal receives when passing through birth canal mother. Further colonization of the body of a young animal comes from this brood of evolutionarily grounded microflora received from the mother. It should be noted that in a healthy female, the fetus in the uterus is sterile until the beginning of labor. However, a properly formed (selected in the process of evolution) normal microflora of an animal's body in its entirety does not immediately inhabit its body, but within a few days, having time to multiply in certain ratios. V. Brown gives the following sequence of its formation in the first 3 days of a newborn's life: bacteria are found in the very first samples taken from the newborn's body immediately after birth. So, on the nasal mucosa, at first, coagulase-negative staphylococci (S. epidermidis) were predominant; on the pharyngeal mucosa - the same staphylococci and streptococci, as well as a small amount of epterobacteria. In the rectum on the 1st day, Escherichia coli, enterococci, the same staphylococci were already found, and by the third day after birth, a microbial biocenosis was established, mainly normal for the normal microflora of the large intestine (W. Braun, F. Spenckcr u. A. , 1987).

4. Othe differences of the microflora of the body of different species of animals

The above obligate representatives of the microflora are characteristic of most domestic, agricultural mammals and the human body. Depending on the type of animal, the number of microbial groups can rather change, but not their species composition. In dogs, the number of Escherichia coli and lactobacilli in the large intestine is the same as shown in table. 1. However, bifidobacteria were an order of magnitude lower (108 in 1 g), an order of magnitude higher were streptococci (S. lactis, S. mitis, enterococci) and clostridia. In rats and mice (laboratory), the number of lactic acid sticks (lactobacilli) was increased, as well as streptococci and clostridia. In these animals, the intestinal microflora showed a small amount of E. coli and the number of bifidobacteria was reduced. Decreased number of Escherichia coli and guinea pigs(according to V. I. Orlovsky). In the feces of guinea pigs, according to our studies, Escherichia coli were kept in the range of 10 3 --10 4 in 1 g.Bacteroids predominated in rabbits (up to 10 9 - 10 10 in 1 g), the number of Escherichia coli up to 10 2 in 1 g) and lactobacilli.

In healthy pigs (according to our data), the microflora of the trachea and large bronchi, neither quantitatively nor qualitatively, did not differ significantly from the average indicators and is very similar to the human microflora. Their intestinal microflora was also characterized by a certain similarity. For the microflora of the rumen of ruminants, specific features are characteristic. This is largely attributed to the presence of bacteria - fiber breakers. However, cellulolytic bacteria (and generally phnbrolytic bacteria), characteristic of the digestive tract of ruminants, are by no means symbionts of these animals alone. Thus, in the cecum of pigs and many herbivores, an important role is played by such breakers of cellulose and hemicellulose fibers, common with ruminants, such as Bacteroides succi - nogenes, Ruminococcus flavefaciens, Bacteroides ruminicola, and others (VH Varel, 1987).

5. Hnormal microflora of the body and pathogenic microorganisms

Obligate macroorganisms, which are given above, are mainly representatives of pepatogenic microflora. Many of the species included in these groups are even called symbionts of the macroorganism (lactobacilli, bifldobacteria), useful for it. Certain useful functions have been identified in many non-pathogenic species of Clostridia, bacteroids, eubacteria, enterococci, non-pathogenic Escherichia coli, etc. These and other representatives of the body's microflora are called "normal" microflora. But from time to time, less harmless, opportunistic and highly pathogenic microorganisms are included in the microbiocenosis physiological for a macroorganism. In the future, these pathogens can:

b to exist for a more or less long time in the body as part of the entire complex of its auto microflora; in such cases, the carrier of pathogenic microbes is formed, but quantitatively, nevertheless, normal microflora prevails;

b be driven out (quickly or somewhat later) from the macroorganism by useful symbiotic representatives of normal (autochthonous) microflora and eliminated;

b multiply, so as to displace the normal microflora that, with a certain degree of colonization of the macroorganism, they can cause the corresponding disease.

In the intestines of animals and humans, for example, in addition to certain types of non-pathogenic Clostridia, C. perfringens lives in small numbers. In the composition of the entire microflora of a healthy animal, the number of C. perfringens does not exceed 10 - 11 5 per 1 g. huge amount(10 7 --10 9 and more), causing anaerobic infection... In this case, it even displaces the normal microflora and can be detected in the scarificate of the ileal mucosa in almost pure culture. In a similar way intestinal coli infection develops in the small intestine in young animals, only there pathogenic types of Escherichia coli reproduce just as rapidly; with cholera, the surface of the intestinal mucosa is colonized by cholera vibrio, etc.

6. Morphofunctional role and metabolic function of the body's auto microflora

The automicrobial flora acts on the macroorganism after its birth in such a way that under its influence the structure and functions of a number of organs in contact with the external environment mature and form. In this way, they acquire their morphological and functional appearance in an adult animal. gastrointestinal, respiratory, genitourinary tract and other organs. A new field of biological spiders - gnotobiology, which has been successfully developing since the time of L. Pasteur, has made it possible to very clearly understand that many immunobiological features of an adult, normally developed organism of an animal are formed under the influence of the auto microflora of its body. Microbial animals (gnotobiots) obtained caesarean section and then kept for a long time in special sterile gnotobibological isolators without any access to them for any viable microflora, have features of the embryonic state of the mucous membranes communicating with the external environment of the organs. Their immunobiological status also retains their embryonic features. Hypoplasia of lymphoid tissue is observed, primarily of these organs. Microbial-free animals have fewer immunocompetent cellular elements and immunoglobulins. However, it is characteristic that potentially the organism of such a gnotobiotic animal remains capable of developing immunobiological capabilities, and only due to the absence of antigenic stimuli that occur in ordinary animals (starting from birth) from the auto microflora, it did not undergo a naturally occurring development that affects the entire immune system in general, and local lymphoid accumulations of mucous membranes of organs such as the intestines, respiratory tract, eyes, nose, ear, etc. Thus, in the process individual development of an animal's organism, it is from its auto microflora that influences follow, including antigenic stimuli, which determine the normal immunomorphological and functional state of an ordinary adult animal.

The microflora of the animal's body, in particular the microflora of the gastrointestinal tract, performs important metabolic functions for the body: it affects absorption in the small intestine, its enzymes are involved in the degradation and exchange of bile acids in the intestine, and forms unusual fatty acids in the digestive tract. Under the influence of microflora, catabolism of some digestive enzymes of the macroorganism occurs in the intestine; enterokinase, alkaline phosphatase are inactivated, disintegrate, in the large intestine some immunoglobulins of the digestive tract, which have fulfilled their function, are decomposed, etc. The microflora of the gastrointestinal tract is involved in the synthesis of many vitamins necessary for the macroorganism. Its representatives (for example, a number of types of bacteroids, anaerobic streptococci, etc.) with their enzymes are able to break down cellulose, pectin substances, indigestible by the animal organism on its own.

WITHlist of literature

1. Baltrashevich AK et al. Dense medium without blood and its semi-liquid and liquid versions for the cultivation of bacteroids / Scientific Research Laboratory of Experimental Biological Models of the USSR Academy of Medical Sciences. M. 1978 7 p.

2. Goncharova GI To the method of cultivation of V. bifidum // Laboratory work. 1968. No. 2.P. 100-102.

3. I. N. Blokhina E, S. Voronin et al. Guidelines on the isolation and identification of opportunistic enterobacteria and salmonella in acute intestinal diseases of young farm animals / M: MBA, 1990. 32 p.

4. Petrovskaya VG, Marko OP Human microflora in health and disease. Moscow: Medicine, 1976.221 p.

5. Chakhava OV et al. Microbiological and immunological foundations of gnotobiology. M .: Medicine, 1982.159 p.

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FOREWORD

When considering ways to deal with many infectious diseases bacterial and viral etiology more often they focus on pathogenic microorganisms - the causative agents of these diseases, less often they pay attention to the accompanying usual microflora of the animal body. But in some cases, it is the usual microflora that becomes of great importance in the onset or development of the disease, contributing to or preventing its manifestation. Sometimes the usual microflora becomes the source of those pathogenic or opportunistic infectious agents that cause endogenous infection, the manifestation of secondary infections, etc. Under other circumstances, the complex of the usual microflora of the animal's body blocks the pathways and opportunities for the development of the infectious process caused by some pathogenic microorganisms. Therefore, to know the composition, properties, quantitative characteristics, biological significance different groups and representatives of the usual microflora of the body (mammals, including domestic, farm animals and humans) should be doctors, biologists, livestock workers, university professors and scientists.

Introduction

The microflora of the organism of mammals, including agricultural, domestic animals and humans, began to be studied together with the development of microbiology as a science, with the advent of the great discoveries of L. Pasteur, R. Koch, II Mechnikov, their students and collaborators. So, in 1885, T. Escherich isolated from the feces of children an obligatory representative of the intestinal microflora - Escherichia coli, which is found in almost all mammals, birds, fish, reptiles, amphibians, insects, etc. After 7 years, the first data on the value of intestinal sticks for vital functions, health of the macroorganism. S.O. Jensen (1893) established that different types and strains of Escherichia coli can be both pathogenic for animals (cause septic disease and diarrhea in calves) and non-pathogenic, that is, completely harmless and even useful inhabitants of the intestines of animals and a person. In 1900, G. Tissier discovered in the feces of newborns bifigebacter "and - lime: and obligatory representatives of the normal intestinal microflora of the body during all periods of his life. Lactic acid sticks (L. acidophilus) were isolated by Moreau in 1900.

Definitions, terminology

Normal microflora is an open biocenosis of microorganisms found in healthy people and animals (V.G. Petrovskaya, O. P. Marko, 1976). This biocenosis should be characteristic of a perfectly healthy organism; it is physiological, that is, it contributes to the maintenance of the healthy status of the macroorganism, the correct administration of its normal physiological functions. The whole microflora of the animal's body can also be called auto microflora (according to the meaning of the word "auto"), that is, the microflora of any composition (OV Chakhava, 1982) of a given organism in health and disease.

The normal microflora associated only with the healthy status of the body is divided by a number of authors into two parts:

1) an obligate, permanent part, formed in phylogeny and ontogeny v the process of evolution, which is also called indigenous (i.e., local), autochthonous (indigenous), resident, etc .;

2) optional, or transitory.

The auto microflora can periodically include pathogenic microorganisms accidentally penetrating into the macroorganism.

Species composition and quantitative characteristicsmicroflora of the most important areas of the animal's body

As a rule, tens and hundreds of species of various microorganisms are associated with the animal organism. They , as V.G. Petrovskaya and O.P. Marko write (1976), are obligatory for the organism as a whole. Many types of microorganisms are found in many areas of the body, changing only quantitatively. Quantitative variations are possible in the same microflora, depending on the species of mammals. The majority of animals are characterized by general averaged indicators for a number of areas of their body. For example, for the distal, lower parts of the gastrointestinal tract, the following microbial groups are characteristic, found in the contents of the intestine or feces (Table 1).

At the top of the table. 1. Only obligate anaerobic microorganisms are shown - representatives of the intestinal flora. It has now been established that the share of strictly anaerobic species in the intestine accounts for 95-99%, and all-aerobic and facultatively anaerobic species make up the remaining 1-5%.

Distribution of microorganisms in the parts of the gastrointestinal tract

Due to the high acidity of gastric juice, the stomach contains a small amount of microorganisms; This is mainly acid-resistant microflora - lactobacilli, streptococci, yeast, sardines, etc. The number of microbes there is 10 3 / g of content.

Microflora of duodenum and jejunum

There are microorganisms in the intestines of a yazda. If they were not in any department, then there would be no peritonitis of microbial etiology when the intestine is injured. Only in the proximal areas of the small intestine there are fewer types of microflora than in the large one. These are lactobacilli, enterococci, sardines, mushrooms, in the lower parts of the growing number of bifidobacteria, Escherichia coli. Quantitatively, this microflora may differ in different individuals. Possible minimum degree of contamination (10 1 - 10 3 / g content), and significant - 10 3 - 10 4 / g The number and composition of the microflora of the large intestine are presented in table 1.

Skin microflora

The main representatives of the skin microflora are diphtherois (corynebacteria, propionic bacteria), mold fungi, yeast, spore aerobic bacilli (bacilli), staphylococci (S. Epidermidis predominates, but S. Aureus is also present in a small amount on healthy skin) ...

Respiratory tract microflora

On the mucous membranes of the respiratory tract, there are most microorganisms in the nasopharynx, behind the larynx their number is much less, even less in the large bronchi, and in the depths of the lungs of a healthy organism there is no microflora at all.

In the nasal passages there are diphtheroids, primarily cornebacteria, persistent staphylococci (resident S. epi dermidis), Neisseria, hemophilic bacteria, streptococci (alpha-hemolytic); in the nasopharynx - corynebacteria, streptococci (S. mitts, S. salivarius, etc.), staphylococci, neisseoia, vailoNella, hemophilic bacteria, more transient enterobacteria, bacteroids, fungi, enterococci, B. lactobacillus, aerobic bacteria is, etc.

The microflora of the deep-lying parts of the respiratory tract has been studied less (A - Halperin - Scott et al., 1982). In humans, this is due to the difficulty of obtaining material. In animals, the material is more accessible for research (you can use killed animals). We studied the microflora of the middle respiratory tract in healthy pigs, including their miniature (laboratory) variety; the results are presented in table. 2.

The first four representatives were detected constantly (100%), less resident (1 / 2-1 / 3 cases) were identified: lactobacilli (10 2 -10 3), Escherichia coli (10 2 -S 3), mold fungi (10 2 -10 4), yeast. Other authors noted the transient carriage of Proteus, Pseudomonas aeruginosa, Clostridia, representatives of aerobic bacilli. In the same plan, we once identified Bacteroides melaninoge - nicus.

Microflora of the birth canal of mammals

Recent studies, mainly by foreign authors (Boyd, 1987; A. V. Onderdonk et al., 1986; J. M. Miller et al., 1986; A. N. Masfari et al., 1986; H. Knothe u . a. 1987), showed that the microflora colonizing (i.e., inhabiting) the mucous membranes of the birth canal is very diverse and rich in species. The components of normal microflora are widely represented, and there are many strictly anaerobic microorganisms in its composition (Table 3).

However, a properly formed (selected in the process of evolution) normal microflora of an animal's body in its entirety does not immediately inhabit its body, but within a few days, having time to multiply in certain ratios. V. Brown gives the following sequence of its formation in the first 3 days of a newborn's life: bacteria are found in the very first samples taken from the newborn's body immediately after birth. So, on the nasal mucosa, at first, coagulase-negative staphylococci (S. epidermidis) were predominant; on the pharyngeal mucosa - the same staphylococci and streptococci, as well as a small amount of epterobacteria. In the rectum on the 1st day, Escherichia coli, enterococci, the same staphylococci were already found, and by the third day after birth, a microbial biocenosis was established, mainly normal for the normal microflora of the large intestine (W. Braun, F. Spenckcr u. A. , 1987).

Differences in the microflora of the body of different types of animals

The above obligate representatives of the microflora are characteristic of most domestic, agricultural mammals and the human body. Depending on the type of animal, the number of microbial groups can rather change, but not their species composition. In dogs, the number of Escherichia coli and lactobacilli in the large intestine is the same as shown in table. 1. However, bifidobacteria were an order of magnitude lower (108 in 1 g), an order of magnitude higher were streptococci (S. lactis, S. mitis, enterococci) and clostridia. In rats and mice (laboratory), the number of lactic acid sticks (lactobacilli) was increased by the same amount, there were more streptococci and clostridia. In these animals, the intestinal microflora showed a small amount of E. coli and the number of bifidobacteria was reduced. The number of Escherichia coli is also reduced in guinea pigs (according to V.I.Orlovsky). In the feces of guinea pigs, according to our studies, Escherichia coli were kept in the range of 10 3 -10 4 in 1 g.Bacteroids prevailed in rabbits (up to 10 9 -10 10 in 1 g), the number of Escherichia coli was significantly reduced (often even up to 10 2 in 1 g) and lactobacilli.

For the microflora of the rumen of ruminants, specific features are characteristic. This is largely attributed to the presence of bacteria - fiber breakers. However, cellulolytic bacteria (and generally fibrolytic bacteria), characteristic of the digestive tract of ruminants, are by no means symbionts of these animals alone. Thus, in the cecum of pigs and many herbivores, an important role is played by such breakers of cellulose and hemicellulose fibers, common with ruminants, such as Bacteroides succi - nogenes, Ruminococcus flavefaciens, Bacteroides ruminicola, and others (VH Varel, 1987).

Normal microflora of the body and pathogenic microorganisms

a) to exist for a more or less long time in the body
as a part of the whole complex of its auto microflora; in such cases, the carrier of pathogenic microbes is formed, but quantitatively, nevertheless, normal microflora prevails;

b) be displaced (quickly or somewhat later) from the macroorganism by useful symbiotic representatives of normal microflora and eliminate;

c) multiply, displacing the normal microflora in such a way that, with a certain degree of colonization of the macroorganism, they can cause the corresponding disease.

In the intestines of animals and humans, for example, in addition to certain types of non-pathogenic Clostridia, C. perfringens lives in small numbers. In the composition of the entire microflora of a healthy animal, the number of C. perfringens does not exceed 10-15 ppm in 1 g. However, in the presence of certain conditions, possibly associated with disturbances in the normal microflora, pathogenic C. perfringens multiplies on the intestinal mucosa in a huge amount (10 7 -10 9 or more), causing anaerobic infection. In this case, it even displaces the normal microflora and can be detected in the scarificate of the ileal mucosa in almost pure culture. In a similar way, intestinal coli infection develops in the small intestine in young animals, only there pathogenic types of E. coli multiply just as rapidly; with cholera, the surface of the intestinal mucosa is colonized by cholera vibrio, etc.

The biological role (functional significance) of normal microflora

Pathogenic and opportunistic microorganisms during the life of an animal periodically contact and penetrate into its body, being included in the general complex of microflora. If these microorganisms cannot immediately cause the disease, then they coexist with another microflora of the body for some time, but more often they are transient. So, for the oral cavity from pathogenic and opportunistic facultative transient microorganisms, P, aeruginosa, C. perfringens, C. albicans, representatives (of the genera Esoherichia, Klebsiella, Proteus; for the intestine, they are the same and even more pathogenic enterobacteriaceae, as well as B fragilis, C. tetani, C. sporogenes, Fusobacterium necrophorum, some representatives of the genus Campylobacter, intestinal spirochetes (including pathogenic, opportunistic) and many others.S. aureus is characteristic of the skin and mucous membranes; for the respiratory tract - he is also pneumococci, etc.

However, the role and significance of the useful, symbiotic normal microflora of the organism is that it does not easily admit these pathogenic facultative-transient microorganisms into its environment, into the spatial ecological niches already occupied by it. The above representatives of the autochthonous part of the normal microflora were the first to take their place on the body of the animal, that is, colonized its skin, gastrointestinal and respiratory tracts, genitals and other areas of the body, even when the newborn passed through the birth canal of the mother.

Mechanisms preventing the colonization (settlement) of pathogenic microflora of the animal body

It has been established that the largest populations of the autochthonous, obligate part of the normal microflora occupy characteristic places in the intestine, a kind of territory in the intestinal microenvironment (D. Savage, 1970). We studied this ecological feature of bifidobacteria, bacteroids and found that they are not evenly distributed in the chyme throughout the entire cavity of the intestinal tube, but spread in strips and layers of mucus (mucins) following all bends of the surface of the mucous membrane of the small intestine. In part, they adjoin the surface of mucosal epithelial cells. Since bifidobacteria, bacteroids and others colonize these sub-regions of the intestinal microenvironment first, many pathogenic microorganisms that later enter the intestine, they create obstacles to approach and fixation (adhesion) on the mucous membrane. And this is one of the leading factors, since it has been established that in order to realize its pathogenicity (ability to cause disease), any pathogenic microorganisms, including those causing intestinal infections, must adhere to the surface of intestinal epithelial cells, then multiply on it, or, penetrating deeper, colonize the same or close subregions, in the area of which huge populations have already developed, for example, bifidobacteria. It turns out that in this case, the bifidoflora of a healthy organism shields the intestinal mucosa from some pathogens, limiting their access to the surface of epithelial membranes and to receptors on epithelial cells, on which pathogenic microbes need to fix.

For many representatives of the autochthonous part of normal microflora, a number of mechanisms of antagonism in relation to pathogenic and opportunistic microflora are also known:

Production of volatile fatty acids with a short chain of carbon atoms (they are formed by the strictly anaerobic part of the normal microflora);

Formation of free bile metabolites (lactobacilli, bifidobacteria, bacteroids, enterococci and many others can form them by deconjugating bile salts);

Lysozyme production (characteristic of lactobacilli, bifidobacteria);

Acidification of the environment during the production of organic acids;

Production of colicins and bacteriocins (streptococci, staphylococci, Escherichia coli, Neisseria, propionic bacteria, etc.);

Synthesis of various antibiotic-like substances by many lactic acid microorganisms - Streptococcus lactis, L. acidophilus, L. fermentum, L. brevis, L. helveticus, L. pjantarum, etc .;

Competition of non-pathogenic microorganisms related to pathogenic species with pathogenic species for the same receptors on the cells of the macroorganism, to which their pathogenic relatives should also be fixed;

Absorption by symbiotic microbes from the composition of the normal microflora of some important components and elements of nutrient resources (for example, iron) necessary for the vital activity of pathogenic microbes.

Many of these mechanisms and factors that are present in the microflora of the animal's body, combining together and interacting, create a kind of barrier effect - an obstacle to the reproduction of opportunistic and pathogenic microorganisms in certain areas of the animal's body. The resistance of a macroorganism to colonization by pathogens, created by its usual microflora, is called colonization resistance. This resistance to colonization by pathogenic microflora is created mainly by the complex useful species strictly anaerobic microorganisms that are part of the normal microflora: different representatives of the genera - Bifidobacterium, Bacteroides, Eubacterium, Fusobacterium, Clostridium (non-pathogenic), as well as facultative anaerobes, for example, the genus Lactobacil - lus, non-pathogenic E. coli, S. faecalis, S. faecium and others. It is this part of the strictly anaerobic representatives of the normal microflora of the body that dominates in terms of the number of population in the entire intestinal microflora within 95-99%. For these reasons, the normal microflora of the body is often considered as an additional factor in the nonspecific resistance of the body of a healthy animal and a person.

It is very important to create and observe the conditions under which, directly or indirectly, the colonization of a newborn with normal microflora is formed. Veterinary specialists, administrative workers, livestock breeders must properly prepare mothers for childbirth, carry out childbirth, provide colostrum and milk feeding of newborns. We must take care of the state of the normal microflora of the birth canal.

Veterinary specialists need to keep in mind that the normal microflora of the birth canal of healthy females is that physiologically grounded brood of beneficial microorganisms that will determine the correct development of the entire microflora of the body of the future animal. If childbirth is uncomplicated, then the microflora should not be disturbed by unjustified therapeutic, prophylactic and other influences; do not enter into the birth canal without sufficiently weighty indications antiseptic, use antibiotics judiciously.

ConceptOdysbiosis

There are cases when the evolutionarily established ratio of species in the normal microflora is disrupted or the quantitative ratios between critical groups microorganisms of the organism's auto-microflora, or the quality of the microbial representatives themselves changes. In this case, dysbiosis occurs. And this opens the way for pathogenic and conditionally pathogenic representatives of the auto microflora, which can invade or multiply in the body and cause diseases, dysfunctions, etc. auto microflora of the animal organism.

Morphofunctional role and metabolic function of the body's auto microflora

The automicrobial flora acts on the macroorganism after its birth in such a way that under its influence the structure and functions of a number of organs in contact with the external environment mature and form. In this way, the gastrointestinal, respiratory, urogenital tracts and other organs acquire their morphological and functional appearance in an adult animal. A new field of biological spiders - gnotobiology, which has been successfully developing since the time of L. Pasteur, has made it possible to very clearly understand that many immunobiological features of an adult, normally developed organism of an animal are formed under the influence of the auto microflora of its body. Microbial animals (gnotobiots) obtained by cesarean section and then kept for a long time in special sterile gnotobiological isolators without any access to them for any viable microflora have features of the embryonic state of mucous membranes communicating with the external environment of organs. Their immunobiological status also retains their embryonic features. Hypoplasia of lymphoid tissue is observed, primarily of these organs. Microbial-free animals have fewer immunocompetent cellular elements and immunoglobulins. However, it is characteristic that potentially the organism of such a gnotobiotic animal remains capable of developing immunobiological capabilities, and only due to the lack of antigenic stimuli that occur in ordinary animals (starting from birth) from auto microflora, it did not undergo a naturally occurring development, affecting the entire immune system in in general, and local lymphoid accumulations of the mucous membranes of organs such as the intestines, respiratory tract, eyes, nose, ear, etc. that determine the normal immunomorphological and functional state of an ordinary adult animal.

Some methods of monitoring the state of the microflora of the animal's body

Monitoring the state of microflora in specific animals or their groups will allow timely correction of unwanted changes in an important autochthonous part of normal microflora, correct violations due to the artificial introduction of beneficial bacterial representatives, for example, bifidobacteria or lactobacilli, etc., and prevent the development of dysbacteriosis in a very severe forms... Such control is feasible if at the right time to carry out microbiological research species composition and quantitative ratios, primarily in the autochthonous strictly anaerobic microflora of some areas of the animal's body. For bacteriological research take mucus from the mucous membranes, the contents of the organs, or even the tissue of the organ itself.

Taking material. For the study of the large intestine, feces can be used, collected specially using sterile tubes - catheters - or in other ways in a sterile container. Sometimes you need to take content different departments the gastrointestinal tract or other organs. This is possible mainly after the slaughter of animals. In this way, material can be obtained from the jejunum, duodenum, stomach, etc. Taking sections of the intestine together with their contents allows you to determine the microflora of both the digestive canal cavity and the intestinal wall by preparing scrapings, homogenates of the mucous membrane or intestinal wall. Taking material from animals after slaughter also allows a more complete and versatile determination of the normal microflora of the generic upper and middle respiratory tract (trachea, bronchi, etc.).

Quantitative research. To determine the amounts of different microorganisms, material taken from an animal in one way or another is used to prepare 9-10 tenfold dilutions of it (from 10 1 to 10 10) in sterile saline or some kind of sterile liquid nutrient medium (corresponding to the type of microbe). Then from each dilution, ranging from less to more concentrated, inoculated on the appropriate nutrient media.

Since the studied samples are biological substrates with mixed microflora, it is necessary to select media so that each one satisfies the growth needs of the desired microbial genus or species and at the same time inhibits the growth of other accompanying microflora. Therefore, it is desirable that the media are selective. By biological role and its significance in the normal microflora is more important for its autochthonous strictly anaerobic part. Methods for its detection are based on the use of appropriate nutrient media and special methods of anaerobic cultivation; most of the strictly anaerobic microorganisms listed above can be cultivated on a new, enriched and universal nutrient medium No. 105 by AK Baltrashevich et al. (1978). This environment is complex and therefore can meet the growth needs of a wide variety of microflora. The recipe for this environment can be found in the manual "Theoretical and Practical Foundations of Gnotobiology" (Moscow: Kolos, 1983). Various options This medium (without the addition of sterile blood, with blood, dense, semi-liquid, etc.) allows to grow many obligate anaerobic species, in anaerostats in a gas mixture without oxygen and outside anaerostats, using a semi-liquid version of medium No. 105 in test tubes.

Bifidobacteria also grow on this medium if 1% lactose is added to it. However, due to the extremely a large number not always available components and complex composition of medium No. 105, difficulties may arise with its manufacture. Therefore, it is more expedient to use Blaurok's medium, no less effective when working with bifidobacteria, but more simple and accessible to manufacture (Goncharova G.I., 1968). Its composition and preparation: liver broth - 1000 ml, agar-agar - 0.75 g, peptone - 10 g, lactose - 10 g, cystine - 0.1 g, table salt (chemically pure) - 5 g. broth: 500 g of fresh beef liver cut into small pieces, pour 1 liter of distilled water and boil for 1 hour; defended and filtered through a cotton-gauze filter, topped up with distilled water to the original volume. Melted agar-agar, peptone and cystine are added to this broth; set pH = 8.1-8.2 with 20% sodium hydroxide and boil for 15 minutes; let stand for 30 minutes and filtered. The filtrate is brought to 1 l with distilled water and lactose is added to it. Then poured into tubes of 10-15 ml and sterilized with flowing steam fractionally (Blokhina I. N., Voronin E. S. et al., 1990). '

In order to impart selective properties to these media, it is necessary to introduce appropriate agents inhibiting the growth of other microflora. For the detection of bacteroids, these are neomycin, kanamycin; for spirally curved bacteria (for example, intestinal spirochetes) - spectinomycin; for anaerobic cocci of the genus Veillonella - vancomycin. To isolate bifidobacteria and other gram-positive anaerobes from mixed populations of microflora, sodium azide is added to the media.

To determine the quantitative content of lactobacilli in the material, it is advisable to use Rogosa salt agar. Selective properties are given to it by the addition of acetic acid, which creates pH = 5.4 in this environment.

A non-selective medium for lactobacilli can be milk hydrolyzate with chalk: 1 g of pancreatin powder and 5 ml of chloroform are added to a liter of pasteurized, skim milk (pH -7.4-7.6), free of antibiotic impurities; shake periodically; put for 72 hours in a thermostat at 40 ° C. Then filtered, set pH = 7.0-7.2 and sterilized at 1 atm. 10 min. The resulting hydrolyzate is diluted with water 1: 2, 45 g of chalk powder and 1.5-2% agar-agar sterilized by heating are added, heated to melt the agar and re-sterilized in an autoclave. The medium is mown before use. If desired, a selection agent can be added to the medium.

It is possible to identify and determine the level of staphylococci on a fairly simple nutrient medium - glucose saline mesopatamia agar (MPA with 10% table salt and 1-2% glucose); enterobacteriaceae - on Endo medium and other media, the recipes for which can be found in any manuals on microbiology; yeast and fungi - on Sabouraud's medium. It is advisable to detect actinomycetes on the medium SR-1 Krasilnikov, consisting of 0.5 potassium phosphate disubstituted. 0.5 g of magnesium sulfate, 0.5 g of sodium chloride, 1.0 g of potassium nitrate, 0.01 g of iron sulfate, 2 g of calcium carbonate, 20 g of starch, 15-20 g of agar-agar and up to 1 liter of distilled water ... Dissolve all ingredients, mix, heat until the agar melts, set pH = 7, filter, pour into tubes, sterilize in an autoclave at 0.5 atm. 15 minutes, mow before sowing.

To identify enterococci, a selective medium (agar-M) is desirable in a simplified version of the following composition: add 4 g of disubstituted phosphate, dissolved in a minimum amount of sterile distilled water, 400 mg, also dissolved sodium aide, to 1 liter of melted sterile MPA; 2 g of dissolved glucose (or ready-made sterile solution of 40% glucose - 5 ml). Move everything. After the mixture has cooled down to about 50 ° С, add to it TTX (2,3,5-triphenyltetrazolium chloride) - 100 mg, dissolved in sterile distilled water. Stir, do not sterilize the medium, immediately pour it into sterile Petri dishes or test tubes. Entero cocci grow on this medium as small, gray-white colonies. But more often, due to the admixture of TTX, the colonies of euterococci acquire a dark cherry color (the entire colony or its center).

Spore aerobic rods (B. subtilis, etc.) are easily detected after heating the test material at 80 ° C for 30 minutes. Then, the heated material is inoculated with either MPA or 1MPB, and after usual incubation (37 ° C with oxygen admission), the presence of these bacilli is established by their growth on the surface of the medium in the form of a film (on the MPB).

It is possible to determine the number of corynebacteria in materials from various areas of the animal's body using Buchin's medium (produced in finished form by the Dagestan Institute of Dry Nutrient Media). It can be enriched with 5% sterile blood. Neisserias are detected on Bergea's medium with ristomycin: to 1 liter of molten Hotteinger agar (MPA is less desirable) add 1% maltose, sterile dissolved in distilled water (you can dissolve 10 g of maltose in a minimum amount of water and boil in a water bath), 15 ml 2% aqueous solution of blue water (aniline blue water-soluble), solution of rystomycin from; calculation of 6.25 units. per 1 ml of medium. Mix, do not sterilize, pour into sterile Petri dishes or test tubes. Gram-negative cocci of the genus Neisseria grow in small to medium-sized blue or blue colonies. Hemophilic bacteria can be isolated on chocolate agar medium (horse blood) with bacitracin as the selective agent. ...

Methods for detecting conditionally pathogenic microorganisms (Pseudomonas aeruginosa, Proteus, Klebsiella, etc.). Well known or found in most bacteriological manuals.

BIBLIOGRAPHIC LIST

Basic

Baltrashevich AK et al. Dense medium without blood and its semi-liquid and liquid versions for the cultivation of bacteroids / Scientific Research Laboratory of Experimental Biological Models of the USSR Academy of Medical Sciences. M. 1978 7 p. Bibliography 7 titles Dep. in VNIIMI 7.10.78, No. D. 1823.

Goncharova G.I.To the method of cultivation of V. bifidum // Laboratornoe delo. 1968. № 2. S. 100-1 D 2.

Methodical recommendations for the isolation and identification of opportunistic enterobacteria and salmonella in acute intestinal diseases of young farm animals / IN Blokhin E, S. Voronin et al. XM: MBA, 1990. 32 p.

Petrovskaya V.G., Marko O.P. Human microflora in health and disease. Moscow: Medicine, 1976.221 p.

Chakhava OV et al. Microbiological and immunological bases of gnotobiology. M .: Medicine, 1982.159 p.

Knothe N. u. a. Vaginales Keimspektrum // FAC: Fortschr. antimlkrob, u. antirieoplastischen Chemotherapie. 1987. Bd. 6-2. S. 233-236.

Koopman Y. P. et al. Associtidn of germ-free rats with different rnicrofloras // Zeitschrift fur Versuchstierkunde. 1984. Bd. 26, No. 2. S. 49-55.

Varel V. H. Activity of fiber-degrading microorganisms in the pig large intestine // J. Anim. Science. 1987. V. 65, No. 2. P. 488-496.

Additional

Boyd M. E. Postoperative gynecologic infections // Can. J. Surg. 1987.

V. 30, 'N 1. P. 7-9.

Masfari A. N., Duerden B, L, Kirighorn G. R. Quantitative studies of vaginal bacteria // Genitourin. Med. 1986. V. 62, No. 4. P. 256-263.

Methods for quantitative and qualitative evaluation of vaginal micro-fiora during menstruation / A. B. Onderdonk, G. A. Zamarchi, Y. A. Walsh et al. // Appl. and Environ. Microbiology. 1936. V. 51, No. 2. P. 333-339.

Miller J. M., Pastorek J. G. The microbiology of premature rupture of the membrans // Clin. Obstet. and Gyriecol. 1986. V. 29, No. 4. P. 739-757.

less frequently excreted from a healthy body.

The body of an animal normally contains hundreds of species of microorganisms; bacteria dominate among them. Viruses and protozoa are represented by a much smaller number of species. It is often impossible to draw a clear line between saprophytes and pathogenic microbes that are part of the normal microflora. The blood and internal organs of animals are practically sterile. Do not contain microbes and some cavities in contact with the external environment - the uterus, bladder. Microbes in the lungs are quickly destroyed. But in the oral cavity, in the nose, in the intestines, in the vagina there is a constant normal microflora, characteristic of each area of the body (autochthonous). During the prenatal period, the body develops under sterile conditions of the uterine cavity, and its primary seeding occurs when passing through the birth canal and on the first day in contact with the environment. Then, within a number of years after birth, a microbial "landscape" characteristic of certain biotopes of his organism is formed. Resident (permanent) obligate microflora and transient (non-permanent) microflora, incapable of long-term existence in the body, are distinguished among normal microflora.

Normal microflora is a collection of microorganisms found in healthy people and animals, it contributes to the maintenance of physiological functions and a healthy status of the macroorganism. The normal microflora, associated only with the healthy status of the organism, is divided into two parts: 1) the obligate, permanent part that has developed in the process of evolution and 2) the optional, or transient.

3) pathogenic microorganisms that accidentally penetrate into the macroorganism can periodically be included in the composition of the auto microflora.

As a rule, tens and hundreds of species of various microorganisms are associated with the animal organism. Many types of microorganisms are found in different areas body, changing only quantitatively. Most organisms have general averages for a number of areas of their body.

So the microflora of the skin is represented by corynebacteria, propionic bacteria, mold fungi, yeast, spore aerobic rods, staphylococci with a predominance of S. epidermidis, and a small amount of S. aureus (the one that is constantly isolated in otitis media).

Due to the high acidity, the stomach contains a small amount of microorganisms; it is mainly acid-resistant microflora - lactobacilli, streptococci, yeast, sardines, etc. The number of microbes there is 10 * 3 / g of content. Much more abundant, the intestines are inhabited, in the proximal parts of the small intestine there are fewer types of microflora - the breakdown of food occurs due to its own enzymes - in the large intestine there is much more. These are lactobacilli, enterococci, sardines, mushrooms, in the lower parts of the growing number of bifidobacteria, Escherichia coli. In dogs, the number of bifidobacteria 10 * 8 in 1 g, an order of magnitude higher (tabular data) streptococci (S. lactis, S. mitis, enterococci) and clostridia. Quantitatively, this microflora may differ in different individuals.

This table provides a list of the main microorganisms that inhabit the gastrointestinal tract.

The microflora inhabiting the mucous membranes of the birth canal is very diverse and rich in species. In percentage terms, it is represented by: Bacteroids - 17%; Bifidobacteria up to 80%; peptococci and peptostreptococci 20%; Clostridia 1%.

If we compare the microflora of the birth canal with the microflora of other areas of the body, we find that the micro-landscape of the mother is similar in this respect to the main groups of microbial inhabitants of the body of the future organism. It should be borne in mind that in a healthy female, the fetus is sterile until the beginning of labor.

The normal microflora of the animal's body fully populates its body in a few days after birth, having time to multiply in certain ratios. So in the rectum on the 1st day, E. coli, enterococci, staphylococci are already found, and by the third day after birth, a normal microbial biocenosis was established.

On the mucous membranes of the respiratory tract, the most microorganisms are in the nasopharynx area, further along the ascending paths, their number decreases significantly, in the depths of the lungs of a healthy organism there is no microflora at all.

In the nasal passages there are diphtheroids, primarily cornnebacteria, permanent staphylococci (resident S. epidermidis), neisseria, hemophilic bacteria, streptococci (alpha-hemolytic); in the nasopharynx - corynebacteria, streptococci (S. mitts, S. salivarius, etc.), staphylococci, neisseria, vailonella, hemophilic bacteria, more transient enterobacteria, bacteroids, fungi, enterococci, B. lactobacillus, pseudomonas aeruginosa and etc.

tab. from the work of the academician of the Russian Academy of Agricultural Sciences, prof. Intizarova M.M.

Obligate microorganisms are mainly representatives of non-pathogenic microflora. Many of the species included in these groups are necessary (lactobacilli, bifidobacteria). Certain useful functions have been identified in many non-pathogenic species of Clostridia, bacteroids, eubacteria, enterococci, non-pathogenic Escherichia coli, etc. Therefore, they are called "normal" microflora. But in the microbiocenosis physiological for a macroorganism, from time to time, less harmless, opportunistic and pathogenic microorganisms are included. In the future, these pathogens can:

a) to exist in the body for a more or less long time in such cases, the carrier of pathogenic microbes is formed, but quantitatively, nevertheless, normal microflora prevails;

b) be displaced from the macroorganism by useful symbiotic representatives of normal microflora and eliminate;

c) multiply, displacing the normal microflora, and cause the corresponding disease.

For example, pathogenic C. perfrtngens can multiply on the intestinal mucosa in an amount (10 * 7 -10 * 9 and more), causing anaerobic infection. In this case, it even displaces the normal microflora and can be detected in the scarification of the ileal mucosa. In a similar way, intestinal coli infection develops in the small intestine in young animals, only there pathogenic types of E. coli multiply.

Transient microorganisms of the gastrointestinal tract

Name of microbial groups	Number of microbes in 1g. material
Enterobacteriaceae Klebsiela, Proteus, Enterobacter, Citrobacter	0 – 10*6
Pseudomonas	0 – 10*4
Staphylococci incl. Epidermidis, S.aureus	103 – 104
Streptococci	Up to 10 * 7
Diphtheroids	0 – 10*4
Aerobic bacilli subtilis	103 – 104
Mushrooms, actinomycetes	10*3

tab. from the work of the academician of the Russian Academy of Agricultural Sciences, prof. Intizarova M.M.

Pathogenic and opportunistic microorganisms during the life of an animal periodically contact and penetrate into its body, being included in the general complex of microflora. So, for the oral cavity from pathogenic and opportunistic facultative transient microorganisms, P, aeruginosa, C. perfringens, C. albicans, representatives (of the genera Esoherichia, Klebsiela, Proteus; for the intestine, they are also more pathogenic enterobacteria, and also B. fragilis, C. tetani, C. sporogenes, Fusobacterium necrophorum, some representatives of the genus Campylobacter, intestinal spirochetes.S. aureus is characteristic of the skin and mucous membranes; for the respiratory tract, it is also pneumococci, etc.

The optional microflora of the birth canal is most often represented by the following varieties.

tab. from the work of the academician of the Russian Academy of Agricultural Sciences, prof. Intizarova M.M.

Veterinary specialists and breeders should bear in mind that the normal microflora of the birth canal of healthy females determines the correct development of the entire microflora of the body of the future animal. Therefore, it should not be violated by unjustified therapeutic, prophylactic and other influences; do not enter antiseptic agents into the birth canal without sufficiently weighty indications.

Veterinary clinic "VetLiga" carries out the collection of material with subsequent transfer to the infectious diseases hospital on weekdays, with a preliminary appointment by phone. 2 300-440