Importance of microflora in zooanimalsWhat is Microflora?• living microorganisms that are so small that they can be seen only with a microscope and that maintaina more or less constant presence in a particular areae.g. the pharynx or the rumen, includes bacteria,viruses, protozoa, fungi .• Microflora is the mixture of microorganismsthat are regularly found at any anatomical site of human body.In human microflorapresent in:Skin,elementary tract, urogenetal tract, ears, mouth (i.e oral cavity), nose (I.
erespiratory tract) and eyes The microflora of the digestive tractof humanHuman stomach has small number of bacteria because of thehigh acidity of stomach. However,certain bacteria can survive in stomach, forexample, Helicobacter pylori who wasdiscovered in human stomach in 1980’s. Recently known that this bacteria is thecause of peptic ulcer and gastritis.Human small intestine have small number of bacteria i.e. Streptococci, Lactobacilli and also yeast (Candidaalbicans).
In the lower part of small intestine, ileum (is a part at thejunction of small intestine and large intestine), Microflora are present inbigger number as compared to first part of small intestine. Large intestinecontains a great variety of bacteria. Colon in the middle part of largeintestine and bacteria reside in it. The species of bacteria which reside thereare Bifidobacterium, Coliforms (E.
coli), Bacteroides, Eubacterium, Lactobacillus, Clostridium and Streptococcus. About 20% of feces consistof bacteria in a normal person. These bacteria come from the last part of largeintestine-colon. Microflora ofdigestive tract of herbivores:From herbivores, we discuss cow because cow is a ruminant. Cows are not the only ruminant animals.
Examples of otherruminants are gazelles, giraffes, moose, antelope, caribou, sheep, goats, anddeer. Herbivores are animals that eat plants like kangaroos, llamas and camelshave modified stomach similar to rumens.Rumen is a home for billions and billions of microbes thatinclude bacteria, protists, fungi and some viruses. Microbes of rumen aredifferent from complex microbe organisms that assist one another to help in thedigestion of food.Hay is eaten by ruminants like cow. It is made up ofcellulose and polymers of long molecules that the animal cannot digest.Microbes can help in digestion of these cellulose and polymer molecules. Theybreak down the cellulose and polymers into small catabolic bits which the cowcan digest and absorb.
Microbes play this activity by special enzymes toconvert cellulose into small digestable particles. Microflora of the respiratory tract:Theupper part of respiratory tract is a habitat for a large number of species ofbacteria so upper respiratory tract lacks ciliated epithelium which help incleansing action. For instance, nostrils are a colony of enourmous number ofbacteria i.e. Staphylococcusepidermidis.Microbes of the Skin:Epidermis of the skin of human is not a fertile region formicroorganisms to live because skin surface is dry and acidic upto a littleextinct while microbes require moist region for their proper growth. Forinstance, Propionibacterium acneand the Staphylococcus epidermidis.Microflora of the Nostrils:Nostrils are moist due to the presence of mucus inside and itbecomes a habitat for Gram-positive bacteria i.
e. Staphylococcus aureus.There are many dissimilar types of kinship that the body caninduce with the microflora.
These are:1-MutualismIt is a “mutual benefit”, as both organisms get benefit fromassociation from each other. For instance, E. coli synthesize and secretevitamin K and B12 which is profitable for host. In return, E.
coli gets warm& nutrient and moist rich environment for its better survival.2-Commensalism:In this type of association, one organism gets benefit whilethe other is neither benefited nor harmed. Bacteria have no commensalismrelationships with human beings. If bacteria present in our body or on thebody, they play a role which is either beneficial (antagonism of microbes) orharmful.Opportunistic(Pathogenic):E. coli is present in the digestive tract of human and otherorganisms where it causes no harm and consequently no disease.
But when itenters into the urogenital tract of organisms, it may be harmful (pathogenic).Staphylococcusaureus is a bacterium of nose microflora found in the upper portionof respiratory tract. If it gains entry into the cells by any wound or bleedingor burn it becomes harmful may be pathogenic.
Characteristics ofMicrofloraMajor characters of microflora are given below:Not disease causing:Microflora are present inside the body and also on the body.They do not induce diseases in the healthy animals. Very enourmous in number:Microflora are very abundant in number. They are present inliving organisms abundantly. For example, a healthy human has about 1013 bodycells but microflora individuals are approximately 1014 in human body.
Onefourth of feces contain bacteria.Found externally to the body:Mostly, microflora are found on external surface to the bodyas on the skin, in the surroundings of eyes, in nose, in throat and also foundon internal surfaces as lower parts ofurethra and in large intestine.Benefits of microflora:• Preventing colonization by microbialanatgonism competing with nutrients and space and produce toxic condition orenvironmental condition to keep harmful pathogens away (acidity in vagina).• Develop immune system by keeping itactive by providing antigens.• Microflora are essential for us to survive.• They gain their food from the stuff in our pie hole.• If colonies of bacteria are worn out by poisons orantibiotics, they must be replaced otherwise we would die ultimately.• They provide a host defence mechanism by taking control on ecologicalniches for bacteria, e.
g. the intestinal villi.• Bacteria produce and excrete various compounds like vitamin B12 andvitamin K in the intestine which are important nutrients for host.• The oral microflora assists in immunity through inducing low level ofcirculating and secretory antibiotics that kill pathogens. In other words, theyenhance body’s immunity.• The oral bacterial flora kill nonindigenous species by producinginhibitory fatty acids, peroxides and bacteriocins (it is a protein and bacreria produce it,it helps in stamping and killing microbes).
• Microflora help to digest food as they break downfoodstuffs that are normally indigestible by the host into forms that areeasily digestible by the hosts.• The Microflora protects the host from infection byharmful pathogenic organisms.• They produce antibacterial substances as by product ofmetabolism, so they have a local antibiotic effect which retard the attack ofinvaders on host.• They stimulate an immunological response (anantibody-mediated immune response) as they act as antigens in the human body.Disadvantages of microflora:• Microflora is harmful when overgrown (i.e.
use of antibiotics) andmisplaced (i.e. urinary tract flora may placed with facel flora).• Microflora may also cause disease in following conditions:• If individual become immunocompromised.• If he change his anatomical location as usual. Conclusion:There are few limitations of microflora to the human body aswell.
For example, most of the microflora are pathogens and may causeinfectious diseases. Similarly, if microflora take control on certain tissues,they can cause infection as well as destruction. Likewise, the Microbe mayabsorb some of the hosts nutrients due to competition, leading to thedevelopment of bacterial antibiotic resistance in humans.