Ruminant GIT Flashcards
Where is the ruminant stomach in the cow?
Left abdomen, takes up all of left and part of right abdomen
What is the largest section of the ruminant stomach?
Rumen
Which three parts of the ruminant stomach make up the forestomach?
Reticulum, rumen, omasum
What four sacs make up the rumen?
Dorsal sac, caudodorsal sac, caudoventral sac, ventral sac
How is the reticulum separated from the rumen?
The ruminoreticular fold
What is the reticular groove?
A channel present in calves, goes from esophagus right to omasum/abomasus and bypasses the reticulum/rumen, formation is stimulated by suckling and CuSO4
How is the rumen divided into sacs?
With pillars, cranial/caudal pillar divide rumen into dorsal/ventral sacs
Where is the atrium ruminis?
The very first sac of the dorsal rumen, where digesta from reticulum enters the rumen
Which section of the ruminant stomach has a honeycombed surface?
Reticulum
Which section of the ruminant stomach has a papillated surface?
Rumen
What layers is the ruminant stomach comprised of?
Mucosa, two muscle layers (Thick inner layer around long axis, thin outer layer running craniocaudally), serosa
Where is the omasum positioned in comparison to the midline?
Slightly to the right of the midline
What is the difference in appearance between the cattle omasum and the sheep/goat omasum?
Cattle: More rounded
Sheep/goat: More bean-shaped
Describe the omasum.
Has tissue folds with variably-sized papilla, meant to squeeze liquid out of/filter digesta and absorb water
Where does the abomasum lay in the abdomen?
On the right abdominal floor
What are the parts of the abomasum?
Fundus, body, pylorus
What is unique about the abomasum?
Glandular, has large mucosal folds, torus narrows pylorus, has a double layer of muscle
What are the three types of glands of the abomasum?
Cardiac glands, gastric glands, pyloric glands
Damage to which branch of the vagal nerve is less serious?
Ventral vagal trunk, can have no effects to paralysis of forestomach (Dorsal trunk results in almost entire paralysis of rumen, if both damaged, abomasum can still contract somewhat)
Where is the ruminant stomach attached to the body?
The dorsal sac of the rumen is attached to the abdominal wall
What is the largest chamber of the ruminant stomach at birth?
Abomasum
How is the duodenum placed in the ruminant body?
Rises dorsally from abomasum, descends to pelvis with flexure, then ascending duodenum
What does the jejunum look like in the ruminant?
Short coils, free margin of common mesentery, position variable depending on gut distension
What does the ileum look like in the ruminant?
Short, attached to cecum via the ileocecal fold
What is the widest part of the ruminant intestine?
Cecum
Which two species have a spiral colon?
Cow (1.5-2 turns) and sheep (3-4 turns)
What are the two sides of the spiral colon called?
Centripetal (Inner) and centrifugal (Outer)
What are the four lobes of the ruminant liver?
Left lobe, quadrate lobe, right lobe, caudate lobe
How is the ruminant liver suspended in the abdomen?
Triangular ligaments, round ligament, lesser omentum, surrounding organs
Describe the ruminant pancreas.
Attached to the liver, left lobe crosses dorsal to rumen and ventral to liver, right lobe runs with descending duodenal mesentery, cattle: one pancreatic duct that enters duodenum after the bile duct, small ruminants: pancreatic duct enters with bile duct
Describe the stomach in the calf as compared to an adult cow.
Large abomasum with full glandular function in a few days, small ruminoreticulum and abomasum, fore-stomach walls are thin with papillae
How does the calf stomach develop?
Solid diet starts to be incorporated around 2-3 weeks, rumen surpasses size of abomasum around 8 weeks, twice the size of abomasum around 12 weeks, development continues with continuous stimulation from forage/fermentation/stretching of stomach, liver starts on midline then moves right as the stomach grows
What are the phases of development of the calf?
Milk diet: 0-2 or 3 weeks
Mixed diet (Transitional adaption to solid food): 3-8 weeks
Solid diet: 8 weeks, anatomy/physiology of an adult
