Lecture 3: The Ruminant Stomach Flashcards
what are the 4 compartments of the ruminant stomach?
- reticulum
- rumen
- omasum
- abomasum
name some ruminant species other than cattle.
deer, sheep, goats, elk, antelope, moose, giraffe, camels, llamas
what is unique about the compound stomach? why was it developed?
it provides an upper digestive tract capable of promoting growth of fermentative microorganisms which produce unique enzymes that can break down the low quality foodstuffs ingested (ie cellulose)
what structures can be seen from the left side in normal anatomic orientation?
- reticulum
- part of abomasum
- rumen (specifically cranial sac, insula and ventral sac)
what structures can be seen from the right side in normal anatomic orientation?
reticulum
omasum
abomasum
pylorus
what structures can be seen from the dorsal view in normal anatomic orientation?
rumen spleen liver omasum abomasum
which side does the rumen occupy almost all of?
the left abdominal cavity
which surface of the rumen lies adjacent to the diaphragm and left abdominal wall?
the parietal surface
which side of the rumen faces the intestines, liver, omasum and abomasum?
the visceral surface
- which side of the body is most of the reticulum located?
2. describe its anatomical location
- primarily on the left
2. it lies in the most cranial compartment, dorsal to the xiphoid process of the sternum
which side of the body is omasum located? and descibe the location of the omasum
it is located cranially on the the RIGHT side of the abdominal cavity, caudal to the reticulum
describe the location of the abomasum
it is located on the right ventral floor of the abdominal cavity dorsal and caudal to the xiphoid process
how is the rumen attached in the body?
it is only attached to the abdominal wall dorsally. this allows great freedom of movement.
how does the cranial sac of the rumen communicate with the reticulum?
the ruminoreticular orifice
what surrounds the ruminoreticular orifice? (2 things)
the ruminoreticular fold and the esophagus
how does the esophagus incompletely surround the ruminoreticular orifice?
via the cardia
what is located on the mucosal surface of the rumen?
ruminal papillae
what 3 things does the reticulum communicate with and how?
- the esophagus at the cardia
- the cranial sac of the rumen via the ruminorecticular orifice
- the omasum via the reticulo-omasal orifice
what is located along the cranial wall of the reticulum extending from the cardia to the reticulo-omasal orifice?
the reticular groove
what is the function of the reticular groove?
the reticular groove consists of two muscular folds. when they contract, ingesta can bypass the rumen and to directly to the omasum
what is the omasal groove?
it is a continuation of the reicular groove in the omasum. the omasal groove bypasses the omasum.