Digestive System GIT - Ruminants Flashcards
Where is the oesophagus located?
begins at the pharynx, descends dorsal to trachea to the middle of the neck
in the midneck, where does the oesophagus lie?
lies on the left dorsolateral aspect of the trachea, then regaining a median position above the trachea
after the midneck, where is the oesophagus located?
it continues beyond the tracheal bifurcation then passes over the heart before penetrating the oesophageal hiatus
what are the primary locations for oesophageal foreign body?
the cervical region, thoracic inlet, base of the heart, hiatus of the diaphragm and cardia of the rumen
antiperistalsis?
reversed peristalsis
what is the tunica muscularis of the oesophagus capable of?
capable of reversed peristalsis
the tunica muscularis (of oesophagus) is entirely … muscle in ruminant and dog?
skeletal
the tunica muscularis (of oesophagus) is entirely … muscle in human and chicken?
smooth muscle
what type of muscle is the tunica muscularis (in the oesophagus) for horse and cat?
it is smooth muscle for the distal third but the rest is skeletal muscle
what makes up the forestomach of ruminants?
rumen (reticulum), omasum, abomasum (glandular)
proventriculi?
forestomach
what kind of fermenters are ruminants?
foregut
size of reticulum compared to the ruminoreticular compartment?
small
what does the reticulum serve as?
serves as a pump that allows liquid to flow into and out of the rumen
where are the rumen and reticulum located?
they occupy the entire left part of the abdominal cavity, extending from the diaphragm at about 7th rib to pelvis
where does the reticulum lie?
medial to the 6th to 8th ribs on the left side with the cranial wall at about the level of the elbow
what is the rumen divided into?
it is partially divided into sacs
what is the right surface of the forestomach covered by?
by the lesser omentum
where does the omasum lie?
in the lower part of the cranial abdomen between reticulum and abomasum
the cranial rumen is to the left and the liver on the right
where does the abomasum lie?
largely on the abdominal floor at about the midline
what does the abomasum have? which portions have this?
fundus, the body and pyloric portion
inside the forestomach, explain the grooves?
the grooves correspond with thickened smooth muscle pillars
what do ruminal pillars divide? what other name do they have?
they divide the dorsal and ventral ruminal sacs
(longitudinal groove/pillar)
what do the coronary pillars divide?
the caudal blind sacs
what does the caudal pillar separate?
the blind sacs
what does the cranial pillar divide?
the dorsal and cranial sacs
what kind of papillae are in the forestomach?
peg like mucosal projections
structure of omasum?
it forms leaf-like folds, or foliae
folds on the omasum in the forestomach?
increases surface area and allows absorption of VFA’s
why does the internal part of the forestomach vary?
according to age, diet and location
slide 11
is the oesophagus-tunica muscularis entirely skeletal in cows and dogs?
yes
at which location does the oesophagus of the cow enter at?
7th ICS
ICS?
ileocolonic sphincter
can the gastric groove be mimicked by drugs in older animals?
yes
does the omasum have the fundus, body and pyloric portion?
no - the abamasum does though
reticulum?
distinctive pattern formed by ridges that outlines 4-5 sided cells
which compartment of the stomach is covered with the lesser omentum?
omasum
which compartment of the stomach is largest at birth?
abomasum
what is not a function of the omentum?
digestive
can the omentum adhere to adjustant structures, which are used in abdominal surgery to seal tissue?
yes
do omental sheets ec,se the sace named the epiploic foramen
which part of the large colon is modified?
ascending
which cranial nerve controls the contractions of the rumen and reticulum?
vagus
what kind of fermenters are cows?
foregut
what is the function of the enteric nervous system?
interacts with intestinal microbes
interacts with intestinal immiune systems
interacts with endocrine systems
helps to maintain mucosal defence barrier function
