Friday, May 24, 2024

The Digestion Process in Ruminant Animals

In this article, we will be discussing about the digestion process in the ruminant animals. The ruminants have a digestive system that is quite different from the monogastric animals. 

The rumen consists of pillars, rhythmic contraction of these pillars causes the rumen to contract and expand leading to a mixing of its contents. The rumen content is made up of a more liquid part at the bottom and a dense floating raft of solid, mainly fibrous materials. 

It is this dense floating fibrous material that the ruminant is seen further chewing (regurgitating). The act of regurgitation reduces the particle size of the fibrous materials thereby increasing surface area for attack by the microorganisms in the rumen and reticulum.

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The Digestion Process in Ruminant Animals

1. Carbohydrate Digestion in the Rumen

The first micro-organism to attack food in the rumen is the fungi. Secrets enzymes break down the surrounding fibers thereby reducing the physical strength of food particles and allowing the entry of bacteria and protozoa. 

The rumen is an anaerobic (oxygen-free) environment under this condition the protozoa and bacteria secrete enzymes that can breakdown the B-linkage in forages and 1 other fibrous feed materials to produce pyruvic acid (pyruvate) which is further broken down (Oxidized) to produce volatile fatty acid (VFA). 

The major fatty acids produced in the rumen are acetic acid, propionic acid, and butyric acid. Others are valeric, and iso-butyric obtained from the microbial metabolism of protein. The VFA produced from the incomplete digestion of carbohydrates is absorbed through the rumen wall.

You should note that the energy produced during aerobic fermentation is lower than what is produced under aerobic (dependent on oxygen) fermentation where the end product is carbon dioxide and water.

2. Protein Digestion in the Rumen

Some of the protein consumed by the ruminants may escape microbial fermentation in the rumen and pass unchanged into the abomasums. Some of these proteins get into the abomasums which can be digested by the normal enzymic digestion that takes place in the abomasums is extremely important in ruminant nutrition and has been given various names such as By-Pass Protein, Rumen Escape Protein, Rumen Undergraduate Protein (RUP).

The fraction of dietary proteins that are degraded in the rumen is referred to as rumen-degraded protein (RDP). The end product of the digestion of RDP is simple amino acids, ammarta, and some urea.

Digestion leaves the reticular – rumen through the reticular – omasa orifice to the omasum. The major role of the omasum in the absorption of urge volume of water coming together with the digesta.

3. Digestion In The Hind-Gut

Once the digest enters the abomasums it is subjected to a series of changes through the action of enzymes that is similar to what happens in the simple stomach of the monogastric animal.

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Digestion in the Young Ruminants

The Digestion Process in Ruminant Animals

Ruminants are not born with a range rumen. At birth, the rumen and reticulum together account for about 30% of the volume of the 4 chambers, By the age of 2 months this would have increased to about 70%, and in mature cows, the rumen and reticulum together occupy 85% of the volume. The abomasums on the other hand will have reduced from 70% to 7% of the volume.

In the young ruminants, feeding solely on the dan’s milk the fore-gut digestion does not occur. Rather milk is passed straight from the oesophagus to the rumen through the oesophageal groove. This groove is formed as a result of a reflected action of the young ruminant which is initiated by the act of suckling.   

This is an important aspect of the nutrition of a young calf as milk is not subjected to microbial fermentation which reduces the quality of milk. As the animal matures and begins to nibble on grasses and other solid feed materials, however, the animal loses this ability to close the groove and the rumen begins to develop to what eventually obtains in the adult.

Advantages of Ruminant Digestion Process

1. The presence of the microbial population in the rumen has a marked effect on the nutrient metabolism of the host. The microbial population allows for the effective utilization of fibrous materials, particularly cellulose through the action of protozoa and bacteria that can break down the b-linkage in cellulose.

2. Microorganisms also make use of certain feed components to synthesize other essential nutrients. An example of this is the use of pan protein Nitrogen (NPN) by ruminants to synthesize cellular proteins.

This reduces the dependence on high-quality protein by ruminants and allows the use of compounds like urea to serve as protein use.

3. Microorganisms in the rumen can produce all B-complex vitamins. As a result, they do not need to be supplied in the feed. This is except vitamins A.D and E.

Disadvantages of Ruminant Digestion Process

1. Most dietary proteins are degraded to ammonia and then to microbial protein. In some cases, the microbial protein is lower in quality compared to the dietary protein. This therefore results in wastage.

2. Simple sugars such as glucose and starches are completely broken down into volatile fatty acids. While these acids are readily used by animal tissues, they are used less efficiently for energy than the original carbohydrates.

3. During the fermentation process, as much as 4-10% of the energy consumed is converted to methane and hydrogen gasses which the animal cannot utilize and is wasted as a result of microbial fermentation.

The digestion process in a ruminant animal is a complex activity involving the breakdown of fibrous materials by micro-organisms leaving in the rumen in a symbiotic relationship with the animal. It is therefore not necessary to provide ruminants with all the feed nutrients because some of them can be synthesized through the action of these micro-organisms.

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Benadine Nonye is an agricultural consultant and a writer with over 12 years of professional experience in the agriculture industry. - National Diploma in Agricultural Technology - Bachelor's Degree in Agricultural Science - Master's Degree in Science Education - PhD Student in Agricultural Economics and Environmental Policy... Visit My Websites On: 1. - Your Comprehensive Practical Agricultural Knowledge and Farmer’s Guide Website! 2. - For Effective Environmental Management through Proper Waste Management and Recycling Practices! Join Me On: Twitter: @benadinenonye - Instagram: benadinenonye - LinkedIn: benadinenonye - YouTube: Agric4Profits TV and WealthInWastes TV - Pinterest: BenadineNonye4u - Facebook: BenadineNonye

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