Set 3 Flashcards
(45 cards)
Why are the terms monogastric and polygastric inappropriate?
There are not true multiple stomaches there are just multiple compartments within the one stomach.
What are the names of 2 and 3 compartment units of the ruminant stomach?
Forestomach is the first three chambers and the ruminoreticulum is the first two chambers.
Describe the lining of each of the 4 compartments.
The first three chambers are lines with the non glandular with stratified squamous lining. Reticulum has honey comb cells. Rumen is lined by papillae. Omasum is lined by the parallel laminae. Abomasum is lined by the glandular walls rather than stratified squamous.
Differentiate between ruminal grooves and pillars.
Grooves are external while pillars are internal.
Which forestomach groove is internal?
The reticular groove is the internal groove.
Why must a ruminant animal maintain an upright position continually?
Ruminants must maintain an upright position so that the gas produced in the rumen does not get trapped. Trapped gas will leads go a bloated gut and kill the animal after time. The cardia of the stomach must be above the level of the ingesta so gas can excape.
What is meant by submersion of the cardia in ruminants?
Submersion of cardia is when the ruminant lies in its side. The animal is not able to release gas.
What is another less critical reason for the upright position?
The other reason for an upright position is to leave the newly ate food on top of fluid so it can be sucked back up into the esophagus and chewed again.
What is the structure that allows milk to bypass the rumen in calves? Why is this important?
The reticular groove closure allows bypass of the rumenoreticulum. Rumen meant for digestion of fibrous plants not milk.
Penetration of a nail or wire through the cranial aspect of the reticulum could damage which organ?
Pericardium; heart
What are 4 attachment points of the ruminant stomach?
Diaphragm at the cardia, dorsal adhesion of the dorsal sac to dorsal wall of abdominal cavity and the greater and lesser omentum
Why is the liver and duodenum displaced in an LDA?
The liver and the duodenum are drug by the abomasums so they are displaced in LDL. The lesser omentum attaches to abomasums and liver.
Differentiate between omental bursa and omental recess.
The bursa is the space between the deep and superficial omentums. The recess is where the intestines are contained because it acts as an omental sling.
What part of the ruminant stomach lies in the omental bursa?
The ventral sac of rumen is the part of the rumen that lies within the omental bursa.
The lesser omentum of the ox attaches to what specific part of the gut and to which side of what solid organ?
The lesser omentum extends from the abomasal lesser curvature to the liver and covers the visceral (ventral) surface of liver.
What structure is covered by the lesser omentum in the ox?
The lesser omentums covers the omasum part of the stomach.
What is the location, structure and apparent function of the omasum?
Location: lies to the right of the reticulum, ventral to the liver and dorsal to the initial part of the abomasum into which it drains. Structure and function :contains many parallel laminae that trap ingesta in between themselves and thereby squeeze water out of the fluid ingesta which enters from the reticulum.
How might it be blocked?
The omasum can be blocked due to a cow eating their own placenta. The placenta is fresh material and is poorly digested in the ruminoreticulum and hence can plug up the omasal canal.
Why is the small intestine much longer in ruminants than the horse?
The rumen must have a longer small intestine than a hind gut fermented like a horse because ruminants must digest the rumen bacteria that has been built from the products of rumen fermentation.
Why is the spiral colon of ruminants easily discernable on a left view but not on a right view?
The spiral colon is covered by mesentery on the right view so it is not seen.
How is the muscle coat and “geometry” of the layout of the spiral intestine of pigs different from that of ruminants?
The pigs spiral colon is three dimensional in shape and has larger centripetal coils on the outside and smaller centrifugal coils on the inside. They also have rudimentary bands and sacculations on the cecum and centripetal spiral colon. Pigs also have an ileal papilla that contains erectile tissue where the ileum enters the colon.
How do the first two compartments of the camelid stomach differ from those of ruminants?
The first compartment is like the rumen in that it is the largest compartment. However, it is different from rumen as it lacks papillae and has glands in the wall. The second compartment is also lined by glandular saccules that are more complex than the saccules found within the first compartment. The second compartment has conical papillae which is similar to that of the omasum which had laminae in the rumen.
Why is the lesser omentum so small in the horse?
The lesser omentums is smaller in the horse due to the reduced size of the lesser curvature.
Relate bowel displacement to the main attachment points of the equine cecum/large colon.
The cecum is attached to the dorsal body wall ventral to the right kidney.
