MONOGASTRIC, avian, ruminant, and pseudo-ruminant are the 4 basic types of digestive systems in animals. To choose the correct type of feed for animals, knowledge of these 4 different types of digestive systems is critical.
Various Types of Digestive Systems
Digestion is the process of breaking down feed into simple substances that can be absorbed by the body. Absorption is the taking of the digested parts of the feed into the bloodstream. The digestive system consists of the parts of the body involved in chewing and digesting feed.
This system additionally moves the digested feed via the animal’s body and absorbs the products of digestion. Different species of animals are better able to digest certain types of feeds than others. This difference happens as a result of the various types of digestive systems present in animals.
There are 4 basic types of digestive systems: monogastric, avian, ruminant, and pseudo-ruminant.
MONOGASTRIC DIGESTIVE SYSTEM
A monogastric digestive system has one simple stomach. The stomach secretes acid, resulting in a low pH of 1.5 to 2.5. The low pH destroys most bacteria and begins to break down the feed materials.
Animals with this kind of digestive system are better adapted to eat rations high in concentrates.
Concentrates are highly digestible feedstuffs which might be high in energy and low in fiber.
Concentrates are usually 80 to 90 % digestible. Common concentrates are cereal grains and oil meals. Cereal grains include corn, wheat, barley, and oats. Oil meals include soybean meal, linseed meal, and cottonseed meal.
Examples of monogastric animals are hogs, cats, dogs, and humans.
AVIAN DIGESTIVE SYSTEM
The avian digestive system is present in poultry. This system differs vastly from every other kind. Since poultry do not have teeth, there isn’t any chewing. Poultry break their feed into pieces small enough to swallow by pecking with their beaks or scratching with their feet.
Feed enters the mouth, travels to the esophagus, and empties directly into the crop. The crop is the place the meals is stored and soaked. Food then moves from the crop to the proventriculus. The proventriculus is the stomach in a bird, the place where gastric enzymes and hydrochloric acid are secreted.
From the proventriculus, the food or feed makes its way to the gizzard. The gizzard is a very muscular organ, which usually accommodates grit or stones that function like teeth to grind the food or feed. The food or feed then moves from the gizzard to the small intestine and then to the large intestine.
The nondigestible feeds components then travel into the cloaca. Urine is also emptied into the cloaca. The materials is then passed out of the body through the vent. Digestion in the avian system is very fast.
RUMINANT DIGESTIVE SYSTEM
The ruminant digestive system has a large stomach divided into 4 compartments, namely — the rumen, the reticulum, the omasum, and the abomasum. The ruminant digestive system is present in cattle, sheep, goats, and deer. Ruminant animals eat feed rations that are high in roughages and low in concentrates.
Roughages are feedstuffs that are high in fiber, low in energy, and typically only 50 to 65 % digestible.
Roughages include hay, straw, grazed forages, and silage. Ruminants are totally different from monogastric animals in that they swallow their feed in large portions with little chewing. Later they are going to ruminate, or regurgitate or chew the cod or belch up the feed, and swallow it again.
The regurgitated feed is named a cud. A cud is a ball-like mass of feed brought up from the stomach to be rechewed.
On average, cattle chew their cuds about six to eight instances per day.
Rumen
The first and largest section of the stomach is the rumen. In the rumen, solid feed is mixed and partially broken down. The rumen accommodates hundreds of thousands of micro organism and other microbes that promote fermentation, which breaks down roughages.
The rumen also accommodates microorganisms that synthesize amino acids and B-complex nutritional vitamins. Amino acids are the constructing blocks of proteins and are important for the expansion and maintenance of cells.
Reticulum
The reticulum is the second section of the stomach. The reticulum is a small pouch on the side of the rumen that traps foreign materials, such as wire, nails, and so forth. Since ruminants don’t chew their food before swallowing, they are going to occasionally swallow foreign objects apart from feed.
Omasum
The omasum is the third compartment of the stomach. The omasum produces a grinding action on the feed and removes some of the water from the feed. Hydrochloric acid and digestive enzymes are blended with feed within the omasum.
Abomasum
The abomasum is the fourth compartment of the stomach. The abomasum can be known as the true stomach as a result of it’s just like the stomach in monogastric animals.
Rumen Microorganisms
Ruminants depend on microorganisms for the digestion of roughages. The rumen microorganisms are very diverse and consist of bacteria, protozoa, and fungi. Bacteria are essentially the most numerous rumen microorganisms, at roughly 1 billion bacteria per milliliter of rumen fluid. Bacteria are liable for most feed digestion within the rumen. They break down cellulose to form volatile fatty acids (VFAs).
The VFAs provide the ruminant with 60 to 80 % of its energy needs. Protozoa are usually liable for about 25 % of the fiber digestion within the rumen, despite the fact that a ruminant can survive without any protozoa within the rumen.
Fungi contribute as much as 8 % of the total rumen microorganisms. Fungi are responsible for the digestion of cellulose and lignin in more resistant forages, such as barley straw.
Feed conversion and rate of gain in a ruminant are strongly affected by the type and quantity of microorganisms within the rumen. The rumen should include the suitable proportions of certain types of microorganisms to maximize productivity.
For instance, it’s believed that protozoa can have a destructive impact on protein utilization. The number of protozoa within the rumen is inversely proportionate to the number of bacteria. Therefore, if a ruminant is fed in a manner that’s most conducive to bacteria in the rumen, protein utilization shall be maximized by eliminating or decreasing the number of protozoa in the rumen.
To illustrate, feeding yeast culture to cattle may assist to make sure a healthy population of rumen bacteria.
PSEUDO-RUMINANT DIGESTIVE SYSTEM
A pseudo-ruminant is an animal that eats large amounts of roughage however doesn’t have a stomach with several compartments. The digestive system does some of the same functions as those of ruminants.
For instance, in the horse, the cecum ferments forages. An animal with a pseudo-ruminant digestive system can make the most of large amounts of roughages as a result of the greatly enlarged cecum and large intestine, which provide areas for microbial digestion of fiber.
Pseudo-ruminants usually eat forages as well as grains and different concentrated feeds.
Besides horses, examples of pseudo-ruminants are rabbits, guinea pigs, and hamsters.
Summary:
“Digestion is the method of breaking down feed into simple substances that may be absorbed into the bloodstream. The 4 basic types of digestive systems in animals are monogastric, avian, ruminant, and pseudo-ruminant. Monogastric animals, such as swine, eat rations high in concentrates.
The avian digestive system, found in poultry, is completely different from the other three types of digestive systems. A poultry animal doesn’t have teeth however has a crop, a proventriculus, a gizzard, and a cloaca.
The ruminant digestive system is discovered cattle, sheep, and goats. Ruminants eat feed rations which are high in roughages. The ruminant digestive system has a large stomach divided into 4 compartments — the rumen, the reticulum, the omasum, and the abomasum. A pseudo-ruminant is an animal that eats large amounts of roughages however doesn’t have a four-compartment stomach.
A pseudo- ruminant animal can utilize roughages as a result of an enlarged cecum and large intestine.”
