Which are the common microorganisms of the rumen? Also give their role.
There are a large number of bacteria, archaea and protozoa. Out of the protozoa most are the protozoa most are the ciliates. Some flagellates like Eutodinium, Diplodinium and Sarcodina also occur in the rumen.
The Bacterial populations found in the rumen are cellulose digesters, strach digesters, hemicellulose digesters, sugar methanogenic bacteria, proteolytic bacteria and lipolytic bacteria. Among the bacterial species are Bacteriods, Ruminococcus, Succinimonas, Methanobacterium, Buryrivibrio, Selenomonas, Succinivibrio, Streptococcus, Eubacterium and Lactobacillus. Some of the bacterial populations produces acetate the predominant acid which is present in the rumen. Some bacteria also produce propionate the only fermentation acid which can be converted into carbohydrates by the ruminant. The wide range of bacteria community of the rumen have enzymatic capabilities needed to digest different types of plant components. Some nitrogen fixation activity bacteria but the amount of nitrogen contributed is very low to meet out the need of nutritional requirement of the animal.
The protozoan populations in the rumen also can digest cellulose and starch while other ferment the dissolved carbohydrates. Some species of protozoans are predations of bacterial populations. The proteins of the rumen protozoa are, however, digested by ruminant’s enzymes. The protozoa inside the rumen store a large amount of carbohydrates. Digestion of protozoa take place in omasum and abomasum compartments of the ruminant stomach which is situated very near to rumen.
Most probably protozoa are more easily digested in comparison to bacteria because bacteria have cell walls and higher nucleic acid contents. The fungal microbes have very poor role. However, methanogenic there is sudden change of diet form dry hay to pasture grass. Production of excess of methane can distend the rumen consequently may compress lungs suffocating the animal. This conditions is called bloat of sheep and cattle. Once it develops only puncturing the rumen to release the excess of methane can save the animal. Bloat is also known as ruminal
tympany or tympanism.