Gastrointestinal Tract of Rabbit

advertisement
The basic mammalian digestive system consists of the oral
cavity (mouth), the esophagus, the stomach, the small
intestines, the cecum, the large intestines and the rectum.
The mouth functions in obtaining food and beginning the
mechanical and chemical breakdown of the food. The
esophagus is in essence a tube directing the food bolus
from
the mouth to the stomach.
The stomach takes various forms in mammals and may
actually consist of several chambers although there is only
a
single chamber in rabbits (this is known as being monogastric). The stomach is a major site of chemical and
mechanical breakdown of food in many mammals.
The stomach releases its contents in pulses to the small
intestine where pancreatic juices are added to further
reduce
the food.
Absorption of nutrients and water also begins in the small
intestine. At the end of the small intestine where it
intersects
with the large intestine is a sac like structure known as
the
cecum that houses bacteria.
The rabbit has a simple stomach making up about 15% of
gastrointestinal volume and an unremarkable small
intestine.
The large intestine is well developed, with the caecum
making up about 40% of total gastrointestinal volume; this
is
the main fermenting chamber.
Parts of the digestive system
1-Mouth:The first part of a rabbit's digestive system is the mouth. The
rabbit uses its lips to grab food and pass it back to the teeth to
cut and grind the plant material. Because this plant material
can be coarse and abrasive, the rabbit’s teeth grow
continuously to account for tooth .Then the front teeth
called incisors — four upper and two lower — neatly slice off
pieces of plant matter. The food is then passed to the molars
(the back teeth), where it's chewed into small particles and
finally swallowed.
If fed a diet with too little fiber or plant material, the rabbit’s
teeth will continue to grow without being worn and may become
overgrown.
2-Esophagus
Once food is swallowed, it passes through the
esophagus. The esophagus is essentially a tube that
transfers food from the mouth to the stomach. Rabbits
have a large stomach for their body size to enable them
to eat large amounts of plant material quickly.
3-Stomach
Rabbits have a relatively large stomach to allow for holding
of large meals because they are crepuscular, meaning
they eat primarily at dawn and dusk. Once food is in the
stomach, it begins to be broken down through hydrolytic
and enzymatic digestion, which means acid and enzymes
are used to break down the compounds to a smaller size.
4-Small intestine
The duodenum is the first section of small intetine. The
jejunum is the middle section. The last section is illium.
The small intestine is responsible for
absorbing the nutrients from the food.
The chyme passes into the small intestine from the
stomach. Flow into the small intestine is regulated by the
pyloric sphincter. The small intestine is the place where the
majority of digestion and absorption of nutrients ocurs.
As food travels along it, enzymes break the food down into
individual nutrients that are small enough to pass through
the
lining of the intestine and be absorbed into the blood stream.
Intestine of rabbit
Digestible fiber has nutrients locked away inside it, so the
Colon diverts it to the cecum for processing. The left over
indigestible fiber doesn’t contain any useable nutrients, but it
is still essential to the digestive process, as it has helped
carry the food through the digestive system.
Meanwhile, in the cecum, a colony of special bacteria ferment
the digestible fiber, breaking it down to release the stored
nutrients.
The cecum can absorb some of the nutrients but most need to
go back through the small intestine to be absorbed.
To achieve this, the fermented fiber moves back into the
colon, where it is coated in protective mucus, before being
excreted from the body as special droppings, called cecal
droppings. The rabbit eats these droppings so they pass
through the digestive tract again.
5-Large intestine and cecum
The final sections of the digestive system are the large
intestine and cecum.
The cecum is a blind sac, or pouch, that comes off the
junction of the small and large intestines. It is located
where the appendix is in humans. The large intestine, or
colon, is the section that continues from the small intestine
to the anus of the animal. Any undigested food and all the
fiber from the rabbit's diet will pass from the small intestine
to the large intestine.the indigestable food pass throw
rectum then out of by anus.
. At this point, the rabbit’s digestive system is able to sort
the material into two portions – that which can be further
broken down and used and that which cannot.
Large intestine of rabbit
Go000000oD BYE

Download