Bovine GI Flashcards
4 Chambers of the Ruminant Stomach
- Rumen
- Reticulum
- Omasum
- Abomasum
What takes up basically the entire left side of a cow?
rumen
Where do you examine a cow for rumen fill?
paralumbar fossa (and/or look at cow from behind)
Where does fermentation occur?
rumen, reticulum, and omasum (ferments complex carbs)
Serosa covers what compartments of stomach?
rumen and reticulum (just not dorsally)
Equivalent of simple stomach?
abomasum
Fermentation of Cellulose occurs in _______
Rumen
Rumen Location
left side, ICS 7 to pelvic inlet
Pillar
hard projections that divide rumen into sacs
Sacs of the Rumen (5-6)
- Dorsal
- Ventral
- Caudodorsal (Blind)
- Caudoventral (Blind)
- Ruminal Atrium
- (Ruminal Recess)
Ruminal Recess
a space in the cranial part of the ventral sac, but not a sac itself
Pillars of the Rumen
- Longitudinal (L&R)
- Cranial
- Caudal
- Dorsal and Ventral Coronary (L&R)
- Accessory Pillar (L&R)
Just stare at this for a little bit.
Did you stare?
What external structure corresponds with internal pillars?
grooves
Cardia of the rumen
the space where the esophagus enters the rumen
Gastric Groove
begins at the opening of the esophagus and bypasses the rumen (rumenal groove), reticulum (reticular groove), and omasum (omasal groove)
Purpose of gastric groove?
suckling reflex causes the groove to close and milk runs directly to absomasum (rumen microbe population hasn’t built up and also don’t want fermentation of milk)
3 Layers in the Rumen
- Gas
- Fiber
- Liquid
How many ruminal contractions are normal?
2-5 contractions every 2 minutes
How do contents move during a contraction?
reticulum –> ruminal atrium –> dorsal sac –> ventral sac
Trocar with little red devils
instrument to release gas
Regurgitation
reticular contraction floods cardia and goes back up esophagus and carried by antiperstatic wave
Eructation
forces ruminal gas into cardiac region; ventral sac to dorsal sac, no reticular involvement
Hole between rumen and reticulum?
ruminoreticular orifice
Rumenoreticular fold
U shaped structure on ventral aspect of orifice separating rumen and reticulum
Function of Reticulum
break down complex food, regurg material that is too large to digest
Reticulum location?
left side, close to xyphooid and diaphragm b/n ribs 6 and 7
Hardware Disease
metal in reticulum punctures wall during contractions and can lead to infection or pericarditis
What does a heart with hardware disease sound like?
coins in a washing machine
Withers Pinch test
sign of cranioabdominal pain, frequently used to test for hardware disease
Type of epithelium in rumen and reticulum?
stratified squamous epithelium
Honeycomb?
Reticulum
Papilla in the Rumen
increases surface area for absorption; largest in blind sacs, fewest in ventral sac
Opening between reticulum and omasum
reticuloomasal orifice
Omasum location
right side, deep to ribs 8-11 (or 7-10) and sits against the dome of the diaphragm
Is your omasum thick or thin?
very thick-walled
Is the omasal groove smooth?
yes
What is the inside of the omasum like?
cresecent shaped laminae with omasal papillae that project towards lesser curvature and divide the lumen into narrow and uniform recesses
Function of the Omasum
probably water absorption and digestion
Can you auscultate the omasum?
nope
Biphasic Omasal Contrations
biphasic
1. move ingesta from canal to the recesses
2. mass contraction to remove fluid, and move contents to abomasum
Abomasum Location
ventral floor; fundus by xyphoid, body to left of median plane between omasum and rumen, pylorus is caudal to omasum on right of median plane at ccjxn10
Is the abomasum glandular or non-glandular?
glandular; large mucosal folds to prevent reflux into omasum
Opening between omasum and abomasum?
omasal-abomasal orifice
Can you find lymph nodes in the stomach?
sometimes, at jxn b/n omasum and abomasum
Is there a cardia in the abomasum?
No, think where the esophagus comes in
Torus pyloricus
projects from pyloric region and its function is unknown
Most forceful contractions occur at what point of the abomasum?
pylorus
How do displaced abomasums occur?
alterations in the contractions causes accumulation of gas which then can’t escape’
Fresh ruminants
just had a baby
Stereotypical patient with displaced abomasum?
fresh ruminants, especially cattle but most especially DAIRY cattle
LDA
distends in space between rumen and reticulum and the body wall
RDA
frequently results in abomasal volvulus (twist), EMERGENCY
How do you test for LDA or RDA?
Percussion; stethoscope in parlumbar fossa, flick from tuber coxae to olecranon, focusing on ribs 9-13
Superficial leaf of greater omentum atttaches to ________
left longitudinal groove
Deep leaf of greater omentum attaches to ___________
right longitudinal groove
“Omental Sling”
rumen lays in the supraomental recess (because of where the leaves of the greater omentum attaches)
What side will you find intestines on?
right (primarily)
Is the capacity of intestines great in ruminants?
no, because so much digestion has already occurred in the gastric region (stomach)
Duodenum location
right of median plane; ICS 10 goes vertically, then caudal, then midline @ tuber coxae, turns cranially passes to left of root of mesentery and ends at L1
Where do the intestines sit (the space)?
supraomental recess
Are the parts of the duodenum in cattle the same as in the dog?
yes
Jejunum location
mainly right ventral side, goes dorsally to meet large intestine
Johne’s Disease
caused by mycobacterium paratuberculosis, infected as calves but onset of signs can take 2-6 years, causes protein-losing enteropathy by gradual thickening of intestine, can’t absorb nutrients, diarrhea/weight loss/death (no tx available)
Where do you primarily diagnose/look for Johne’s disease?
ileum (bubbly diarrhea)
Ileocecocolic junction
cecum and colon split by entrance of the ileum (ileocecal orifice in the ileal papilla), then cecocolic orifice to leave
3 Parts of Ruminant Ascending Colon
- Proximal loop
- Spiral loop
- Distal loop
Proximal loop
S-shaped, extends from cecocolic jxn cranially to rib 12, caudal to tuber coxae, cranially to left of root of the mesentery at L1
Spiral loop
lies to left of midline, centripital coils to central flexure to centrifugal coils
Centripital
coils inwards
Centrifugal
coils outward
Distal loop
colon straightens caudally to L5, cranially to right of root of the mesentery at rib 13
Tranverse colon goes which way?
right to left in front of root of the mesentery (L2)
Liver location
almost entirely on right side from rib 6 to 12
Liver Lobes (4)
- Left
- Right
- Caudate
- Quadrate
How to take a liver biopsy in cattle?
ICS10 at level of ventral aspect of tuber coxae, needle pointed toward opposite olecranon
Do cattle have a gallbladder?
yes
Does the bile duct enter through a papilla?
NO, no papilla
Spleen location
left side draped over the rumen, ccjxn 7 to dorsal part of rib 12
Color variation in spleen
females are steel blue, males and babies are more reddish
Shape of spleen
flat and oblong
Do ruminants have a pancreatic duct?
no
Do ruminants have an accessory pancreatic duct?
yes
What papilla do ruminants have in the duodenum?
minor duodenal papilla, and that’s it
