Rumen ecosystem consists of different rumen microorganisms mainly Bacteria, Protozoa and Fungi. The bacteria occupies 50-90 % rumen biomass, whereas Protozoa and fungi occupies 10-50 % and 5-10 % respectively. They are beneficial to the animals, because it contributes in Production of microbial proteins. They have role in production of VFAs which acts as a source of energy.

1. Rumen bacteria
Methanogenic : M. ruminantium, Proteolytic: Bacteroides ruminocola, Lipolytic: Anaerovibrio lipolytica, Ureolytic: Selenomonas Spp,
Ammonial Producing: Bacteroides ruminocola
• Rumen Protozoa • Rumen Fungi
Holotrichs
-use soluble CHO
Entodiniomorphs
- oligotrophs, use starch
1. Neocallimastix
2. Piromyces
3. Caecomyces
4. Orpinomyces
5. Anaeromyces
Isotricha,Blepharoprosthium,
Charon, Dasytricha,
E. bursa, M. medium, etc.
Types Cellulose digester
(Cellulolytic)
Starch digester
(Amylolytic)
Hemicellulose
digester
Pectin
digester
Sugar
utilizing
Acid utilizing
Rod Cocci Cellulytic Non
cellulytic
Formate Oxalate
Examples Fibrobacter
sucinogens,
Ruminococcus
albus,
Fibrobacter
sucinogens
Streptoc.
bovis,
Eubacterium
ruminatium
Bacteroides
ruminocola
Lactobacillus
casei
Vibrio
succino
gens
Oxalobacter
formigens
clostridium
longisporium
R. flavefaciens clostridium
longisporium
Bacteroides
ruminocola
Ruminococcus
albus,
R. flavefaciens
Streptoc.
bovis
L. bifidus
Lifespan 18hrs -do- 20-30 min -do-