ruminant GIT Flashcards
where does the oesophagus run through in the body
-begins at pharynx and runs dorsal to trachea
-lies to the left in mid neck and regions medial position after entering thorax
-continues past the tracheal bifurcation then past the heart and penetrates the diaphragm at the oesophageal hiatus
what is the cow oesophagus capable of
peristalsis and anti peristalsis
locations of choke
cervical region, thoracic inlet, base of the heart, hiatus of the diaphragm and cardia of rumen
what type of stomach does the cow have
complex and composite
4 types of stomachs in the cows
omasum
abomasum (true stomach, glandular)
reticulum
rumen
are cows handgut or foregut fermenters
foregut
which stomach is the fermentation vat
rumen
is the reticulum smaller than the rumen
yes
function of the reticulum
keeps the fluid in the rumen moving, and acts as a pump to allow liquid to flow into and out of the rumen
where are the rumen and reticulum located
occupy the entire left side of the abdominal cavity, extending from the diaphragm at the 7th rib to the pelvis
where does the reticulum lie
medial to the 6th and 8th rib on the left
where is the omasum located
lower part of the cranial abdomen between reticulum and cranial rumen to the left and the liver on the right
where is the abomasum located
lies largley on the abdominal floor at about the midline or just to the right (the pylorus)
3 regions of the abomasum
funds, body, pyloric region
in cows and sheep does the abomasum make contact with the liver
not in cows but yes in sheep
what is the inside appearance of the reticulum
honeycomb
what lines the inside of the rumen
grooves that correspond with thickened smooth muscle pillars on the inside of the rumen
what divides the dorsal and ventral ruminal sacs
luminal pillars
what divides the caudal blind sacs
coronary pillars
what divides the dorsal and cranial sacs
cranial pillar
function of papillae in the fore stomach
increases surface area for the absorption of VFA
what are the 3 gastric groves called
-reticular groove (for rumen and reticulum)
-omasal groove
-abomasal groove
where does the gastric grove pass to and from
starts at the cardia of the reticulum to the abomasum
what is the function of the gastric grove
it allows ingested milk to bypass the forestomach hence avoiding fermentation
what is the omentum
double layered connecting peritoneum between the stomach and abdominal organs/wall
where does attachment of the greater omentum begin
dorsal to the oesophagus
where does the lesser omentum arise
visceral surface of the liver
where does the superficial greater omentum arise from
left side of the rumen
where does the superficial greater omentum arise from
the right side of the rumen
where do both leaves of the greater omentum extend from and attach to
extend ventrally and to the right of the rumen and both leaves attach to the descending duodenum
internal structure of rumen
short/long papillae, stratified squamous epithelium
function of the rumen
storage, fermentation vat, absorbs VFA
internal strut of cow reticulum
long folds with conical papillae with keratinised tips
-has lamina propria, lamina muscularis, tunica muscularis
parts of the small and large intestines
-duodenum, jejunum, ileum
-caecum
-ascending colon
-proximal loop of colon
-spiral colon
-distal loop of colon
-transverse colon
-descending colon
what is the main artery that supplies the stomach
celiac artery
what are the 3 branches of the celiac artery
splenic, left, gastric and hepatic artery
which arteries follow the longitudinal grooves
right (from splenic) and left ruminal arteries (from left gastric)
which arteries follow the lesser curvature of the abomasum
right and left gastric
what arteries follow the greater curvature of the abomasum
right and left gastroepiploic arteries
what artery is the bulk of the intestines supplied by
cranial mesenteric artery
what artery supplies the first part of the duodenum
celiac artery
what artery supplies the descending colon
caudal mesenteric artery
is vagus nerve parasympathetic or sympathetic
parasympathetic
vagus nerve
-innovated in motor and sensory pathways
-controls the contraction of the rumen and reticulum and reflex of gastric grove
is the splanchnic nerve parasympathetic or sympathetic
sympathetic
splanchnic nerves
