GI - Stomach pt 1 Flashcards
List the 4 parts of the ruminant forestomach in order of food transit.
- reticulum
- rumen
- omasum
- abomasum
Match the letters with the correct compartment of the ruminant fore stomach.
A: reticulum
B: Rumen
C: Abomasum
D: Omasum
Like birds, camelids have ______ in their fore stomachs. However, unlike birds, they don’t serve a specific function; rather, they are incidental.
Gastroliths
What type of epithelium lines the rumen?
stratified squamous epithelium
What are trichobezoars?
Where are they found? Why?
What do they mean when found in necropsy?
spherical masses of hair or wool
found in the rumens of younger animals from excessive grooming.
Incidental finding
What are phytobezoards?
What do they mean when found in necropsy?
Spherical masses of plant fibres
Incidental finding
What are the gross lesions of ruminal hyperkeratosis?
club shaped, clumped papillae that may be dark
what leads to ruminal hyperkeratosis?
diets high in concentrates
Vitamin A deficiency
high barley diets
You are doing a necropsy of a cow and look at its rumen. What is your diagnosis? What do you think caused it?
Ruminal hyperkeratosis
diet high in concentrates, vitamin A deficiency, or a high barley diet
What causes ruminal tympany? What’s the other name for this pathology?
inability to eructate gas from rumen
Bloat
Ruminal tympany can lead to death through metabolic and physical effects. Name 2 of these effects.
Decreased venous return
Thoracic compression
What are the gross lesions of ruminal tympany?
- marked abdominal distention with “sawhorse” posture
- blood is dark and clots poorly (indicates death from anoxia)
- subq hemorrhage/edema cranially, non-hemorrhagic edema caudally (inguinal is common) [cranial lymph nodes also affected]
- bloat line within esophagus [cranial congestion, becomes pale near thoracic inlet]
- lung compression/atelectasis
A cow comes in with this posture. What is your primary differential based on this?
Ruminal tympany (bloat)
don’t know which type because we haven’t seen the rumen contents yet
This is the esophagus of a cow. Based on the lesion seen in this photo, what is your diagnosis?
Ruminal tympany (bloat)
we don’t know the type because we haven’t looked at the rumen contents yet.
What are the two main types of ruminal tympany? Label them as acute or chronic
Primary tympany = frothy bloat –> acute + severe
Secondary tympany = gas bloat –> chronic
What causes primary ruminal tympany?
diet high in legumes (alfalfa, clover) or concentrates
How can you tell that it’s primary ruminal tympany?
contents are frothy; gas trapped, not eructed
[froth will disappear with prolonged postmortem interval]
What causes secondary ruminal tympany?
vagal indigestion syndromes
Ruminal drinkers
how can you tell it’s secondary ruminal tympany?
gas is free but retained due to physical or functional defect
ruminal contents may look normal
What are vagal indigestion syndromes?
clinical syndrome, gradual development of abdominal distention due to ruminoreticular distension
classically associated with damage to the vagus nerve; however, absence of vagal damage in the maj. of cases
most common cause is traumatic reticuloperitonitis
other causes include anything resulting in a mass effect near junctions b/t compartments (HANG acronym)
What are ruminal drinkers?
milk escapes the ruminoreticular groove and ends up fermenting in the rumen
also have rumenitis histologically
You receive a cow for necropsy that was in a “sawhorse” stance, and you find a bloat line in the esophagus. You look in the rumen and these are the contents. What is your diagnosis?
Primary ruminal tympany
What is the other name for traumatic reticuloperitonitis? What location is most common for penetration?
hardware disease
cranioventral penetration
What is traumatic reticuloperitonitis?
perforation of the fore stomach (classically the reticulum) due to a sharp foreign body (classically metallic)
How do you prevent traumatic reticuloperitonitis?
Magnets!
what are the possible outcomes for traumatic reticuloperitonitis? the first two you should defs know for exam
- Chronic local peritonitis +/- focal adhesions
- traumatic pericarditis (requires diaphragmatic penetration)
- subperitoneal or subq abscess near xyphoid
- sudden death from hemorrhage (rare)
- septicemia (rare)
- pleuritis/pneumonia
Which bacteria are commonly associated with traumatic reticuloperitonitis?
Trueperella pyogenes
Fusobacterium necrophorum
You find this item in this organ of a cow. What is your diagnosis? Name one bacterium you might find in this cow.
Say this item travelled cranially and penetrated the diaphragm. What other lesion could you find?
Traumatic reticuloperitonitis
Trueperella pyogenes or Fusobacterium necrophorum
you could find traumatic pericarditis
what causes ruminal acidosis?
ingestion of excessive carbohydrates
more common in intense production systems
more likely with sudden increase vs gradual
How does the rumen pH change with ruminal acidosis? Give me normal values and changed values
normal rumen pH = 5.5 - 7.5
ruminal acidosis pH = ≤ 5
Rumen pH generally _____ with postmortem interval.
increases
What is the pathogenesis of ruminal acidosis?
decreasing pH leads to death of normal gram (-) bacteria –> proliferation of Streptococcus bovis –> increased lactic acid production –> decreased pH –> Lactobacillus predominates
What are the gross lesions found with ruminal acidosis? (hint: they are pretty general)
sunken eyes, thick dark blood
variable appearance to the ruminal contents, intestinal contents often watery
mucosa may be difficult to peal
may have a distinct odour
tips of the ruminal papillae may appear white
What are the specific outcomes of ruminal acidosis?
Scarring
Necrobacillary rumenitis (AKA necrobacillosis)
Mycotic rumenitis
What is the etiology of necrobacillary rumenitis?
Fusobacterium necrophorum
What are the gross lesions of necrobacillary rumenitis?
well-demarcated, plaque-like areas of necrosis
bacterial embolization to the liver is common resulting in liver abscesses
What is the etiology of mycotic rumenitis?
Zygomycete funguses (Mucor, Rhizopus, Absidia)
Aspergillus also possible, but more common in abomasum
What are the gross lesions of mycotic rumenitis?
more hemorrhagic, severe, and extensive than necrobacillary rumenitis
often visible from the serosal surface
vasculocentric –> causes infarcts (well demarcated areas of discolouration surrounded by a red rim)
On the L is a rumen and on the R is a liver. What is your primary differential for the cause of these lesions? What is the etiology?
Necrobacillary rumenitis
caused by fusobacterium necrophorum
These are both examples of lesions associated with ______.
Mycotic rumenitis
What is the scientific name of rumen flukes? What are the gross lesions? Pathogenic/non-pathogenic?
Paramphistomatidae sp.
red to pink, similar in size to surrounding rumen papillae
may be associated with some inflammation
non-pathogenic
These things are mixed in with rumen papillae. What is your primary differential?
Rumen flukes, Paramphistomatidae
What is the name of the line formed by the division of the glandular and non-glandular portions of the equine stomach?
Margo plicatus
What is the arrow pointing to? (pig stomach)
Pars esophagea
What is the difference b/t a papilloma and a fibropapilloma?
papilloma is only epithelium proliferating, fibropapilloma is epithelium and underlying dermal mesenchyme
Are fore stomach neoplasm common or rare?
rare
What are the 3 fore stomach neoplasms that we need to know?
Fibropapilloma
Papillomas
Squamous cell carcinoma
What is the etiology of fibropapillomas in the fore stomach? Where are you more likely to find them (specific)?
bovine papillomavirus 2 (BPV-2)
esophagus and esophageal groove of the rumen
What causes papillomas in the fore stomach? Where does it target?
bovine papillomavirus 4
only targets squamous mucosa
Squamous cell carcinoma in the bovine fore stomach is associated with _____
BPV-4
Label the green boxes in this bird stomach
L-most box: proventriculus
R-most box: gizzard
