Reticulorumen
Encyclopedia
The reticulorumen represents the first chamber in the alimentary canal of ruminant
animals. It is composed of the rumen
and reticulum
. The reticulum differs from the rumen with regard to the texture of its lining. The rumen wall is covered in small, finger-like projections called papillae, which are flattened, approximately 0.5 cm in length and 0.3 cm wide in cattle. The reticulum is lined with ridges that form a hexagonal honeycomb
pattern. The ridges are approximately 0.1 - 0.2 mm wide and are raised 0.5 cm above the reticulum wall. The hexagons in the reticulum are approximately 2-5 cm wide in cattle. Despite the differences in the texture of the lining of the two parts of the reticulorumen, it represents one functional space. Microbial fermentation degrades ingested carbohydrates in the reticulorumen to the volatile fatty acids
acetate
, propionate
and butyrate
, and proteins to short peptides, amino acids and ammonia
. This fermentation is anaerobic, and allows the microbes in the reticulorumen to derive the energy
and amino nitrogen
for growth and reproduction. Ruminants absorb the volatile fatty acids across the reticulorumen wall and use them for energy, while the microbes eventually flow out of the rumen into the remainder of the alimentary canal, where they are eventually digested and absorbed. The reticulum, at approximately 5-20 litres, is considerably smaller in capacity than the rumen, which is approximately 100-200 litres in cattle. The oesophageal groove, which links the oesophagus and the omasum
, is located in the reticulum.
Ruminant
A ruminant is a mammal of the order Artiodactyla that digests plant-based food by initially softening it within the animal's first compartment of the stomach, principally through bacterial actions, then regurgitating the semi-digested mass, now known as cud, and chewing it again...
animals. It is composed of the rumen
Rumen
The rumen, also known as a paunch, forms the larger part of the reticulorumen, which is the first chamber in the alimentary canal of ruminant animals. It serves as the primary site for microbial fermentation of ingested feed...
and reticulum
Reticulum (anatomy)
The reticulum is the second chamber in the alimentary canal of a ruminant animal. Anatomically it is considered the smaller half of the reticulorumen along with the rumen. Together these two compartments make up 84% of the volume of the total stomach. The reticulum is located between the rumen and...
. The reticulum differs from the rumen with regard to the texture of its lining. The rumen wall is covered in small, finger-like projections called papillae, which are flattened, approximately 0.5 cm in length and 0.3 cm wide in cattle. The reticulum is lined with ridges that form a hexagonal honeycomb
Honeycomb
A honeycomb is a mass of hexagonal waxcells built by honey bees in their nests to contain their larvae and stores of honey and pollen.Beekeepers may remove the entire honeycomb to harvest honey...
pattern. The ridges are approximately 0.1 - 0.2 mm wide and are raised 0.5 cm above the reticulum wall. The hexagons in the reticulum are approximately 2-5 cm wide in cattle. Despite the differences in the texture of the lining of the two parts of the reticulorumen, it represents one functional space. Microbial fermentation degrades ingested carbohydrates in the reticulorumen to the volatile fatty acids
Volatile fatty acids
Volatile fatty acids are fatty acids with a carbon chain of six carbons or fewer. They are now usually referred to as short-chain fatty acids .They can be created through fermentation in the intestine.Examples include:* Acetic acid...
acetate
Acetate
An acetate is a derivative of acetic acid. This term includes salts and esters, as well as the anion found in solution. Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In...
, propionate
Propionate
The propanoate or propionate ion is C2H5COO− .A propanoic or propionic compound is a salt or ester of propanoic acid....
and butyrate
Butyrate
Butyrate is the traditional name for the conjugate base of butanoic acid . The formula of the butanoate ion is C4H7O2-. The archaic name is used as part of the name of butyrates or butanoates, or esters and salts of butyric acid, a short chain fatty acid...
, and proteins to short peptides, amino acids and ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
. This fermentation is anaerobic, and allows the microbes in the reticulorumen to derive the energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...
and amino nitrogen
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
for growth and reproduction. Ruminants absorb the volatile fatty acids across the reticulorumen wall and use them for energy, while the microbes eventually flow out of the rumen into the remainder of the alimentary canal, where they are eventually digested and absorbed. The reticulum, at approximately 5-20 litres, is considerably smaller in capacity than the rumen, which is approximately 100-200 litres in cattle. The oesophageal groove, which links the oesophagus and the omasum
Omasum
The omasum, also known as the bible, the fardel, the manyplies and the psalterium, is the third compartment of the stomach in ruminants...
, is located in the reticulum.