essay note
SPECIAL SECTION: MICROBIAL DIVERSITY
Rumen microbial ecosystem
D. N. Kamra
Microbiology Section, Centre of Advanced Studies in Animal Nutrition, Indian Veterinary Research Institute, Izatnagar 243 122, India
The inhabitants of the rumen microbial eco-system, a complex consortium of different microbial groups living in symbiotic relationship with the host, act synergistically for the bioconversion of lignocellulosic feeds into volatile fatty acids which serve as a source of energy for the animals. The constraints, imposed by the host and the feed consumed by the animal, under which these microbes have to function, have been discussed.
The eco-system is specialized and buffered in a narrow range of pH, which helps the animal to maintain a very well stabilized eco-system which is not disturbed by the incoming microbial contaminants into the fermentation sac (rumen) through feed and water intake. The microbial ecosystem is well studied for the rumen of domesticated animals like cattle, sheep and goat, but it is poorly studied in buffalo and wild ruminants. The necessity to use molecular biology techniques for identification and characterization of rumen microbes has been emphasized in this review.
IN tropical countries of the world, the ruminants are fed on lignocellulosic agricultural by-products like cereal straws, stovers, sugarcane bagasse, tree foliages and cakes of oil seeds like groundnut, cotton, mohua, neem and mustard.
The efficiency of ruminants to utilize such a wide variety of feeds is due to highly diversified rumen microbial ecosystem consisting of bacteria (1010–1011 cells/ml, representing more than 50 genera), ciliate protozoa (104–106/ml, from
25 genera), anaerobic fungi (103–105 zoospores/ml, representing five genera) and bacteriophages (108–109/ml)1. These numbers might even be larger as majority of them are non-culturable. The synergism and antagonism among the different groups of microbes and even among different
Rumen microbial ecosystem
D. N. Kamra
Microbiology Section, Centre of Advanced Studies in Animal Nutrition, Indian Veterinary Research Institute, Izatnagar 243 122, India
The inhabitants of the rumen microbial eco-system, a complex consortium of different microbial groups living in symbiotic relationship with the host, act synergistically for the bioconversion of lignocellulosic feeds into volatile fatty acids which serve as a source of energy for the animals. The constraints, imposed by the host and the feed consumed by the animal, under which these microbes have to function, have been discussed.
The eco-system is specialized and buffered in a narrow range of pH, which helps the animal to maintain a very well stabilized eco-system which is not disturbed by the incoming microbial contaminants into the fermentation sac (rumen) through feed and water intake. The microbial ecosystem is well studied for the rumen of domesticated animals like cattle, sheep and goat, but it is poorly studied in buffalo and wild ruminants. The necessity to use molecular biology techniques for identification and characterization of rumen microbes has been emphasized in this review.
IN tropical countries of the world, the ruminants are fed on lignocellulosic agricultural by-products like cereal straws, stovers, sugarcane bagasse, tree foliages and cakes of oil seeds like groundnut, cotton, mohua, neem and mustard.
The efficiency of ruminants to utilize such a wide variety of feeds is due to highly diversified rumen microbial ecosystem consisting of bacteria (1010–1011 cells/ml, representing more than 50 genera), ciliate protozoa (104–106/ml, from
25 genera), anaerobic fungi (103–105 zoospores/ml, representing five genera) and bacteriophages (108–109/ml)1. These numbers might even be larger as majority of them are non-culturable. The synergism and antagonism among the different groups of microbes and even among different