equine GI Flashcards
what are some things that can lead to colic in horses
- Gastric ulcers
- small intestinal disease
- colonic disease
- parasites
- peritonitis
GI tract path
stomach
duodenum, jejunum, ileum
cecum
R. ventral colon
* sternal flexure
L. ventral colon
* pelvic flexure
L. dorsal colon
* diaphragmatic flexure
R. dorsal colon
Transverse colon
Descending (small) colon
rectum / anus
where in the GI tract are bands (taenia) located
cecum, colon (ventral, dorsal, small) and pelvic flexure
small segmented pouches of bowel separated by haustral folds
haustra
functions of small intestine
digestion of simple carbohydrates and readily accessible protein
most protein is absorbed in foregut
function of colon
reabsorption of water
some further fermentation
function of cecum
fermentation of some carbs and proteins that escaped digestion in the SI
- cellulose breakdown
creation and absorption of VFAs
where does fermentation occur
cecum and colon
what does fermentation in the hindgut produce
CO2, methane, VFAs
main difference b/w hindgut and foregut digestion
hindgut digestion is largely microbial and not enzymatic as in the foregut
microbial fermentation in the hindgut allows horses to breakdown _______
cellulose
Propionate
used for glucose production
acetate gets converted to - converted to _________ and is used for immediate energy or for fat
synthesis
acetyl CoA
Butyrate
also converted acetyl CoA
what does the mircobiota consist of
bacteria, fungi, protozoa
* Phylum Fermicutes 46-70%
* Bacteroidetes, Proteobacteria, Verrucomicrobia, Actinobacteria, and
Spirochaetes make up 0-15% each.
does microbiota differ in healthy vs sick horses
yuh (or should i say yee)
Diarrheic horses have more Fusobacteria than healthy horses and have
fewer Clostridiales
clinical signs of colic
- Sweating
- Pawing
- Tachycardia
- Tachypnea
- Up and down
- Rolling
- Stretching out
- Shifting
- Biting or looking at sides
- Kicking at abdomen
Stomach is divided into upper squamous stomach and the lower
glandular stomach by the ________
margo plicatus
ulcerations can occur in both upper and lower
Grading systems ESGD (equine squamous gastric disease)
- Grade 0 is normal
- Grade 1-hyperkeratosis
- Grade 2- small, single or multifocal
lesions - Grade 3- large single or extensive
superficial lesions - Grade 4- extensive lesions with areas
of apparent deep ulceration
enteritis
inflammatory disease of small intestine
clinical signs of small intestine strangulation
severe pain, serosanguinous belly tap
Strangulating lipoma
Lipomas form on stalks in the mesentery.
what horses are prone to Inguinal hernia
stallions
enteritis characterized by : Fever, reflux (vomiting is not a thing), leukocytosis, colic that resolves with decompression
Acute : Proximal enteritis
enteritis characterized by Weight loss and panhypoproteinemia (loss of protein)
Chronic/insidious: Inflammatory bowel syndromes, neoplasia
ileal impactions (in SI) can be caused by?
- Feeding coastal Bermuda hay
- Tapeworm infestation (Anoplocephala)
main causes/types of small intestine impactions
- lesions in SI
- ileal impactions
- adhesions (scar tissue)
- Ascaridiasis (worms)
main causes/types of large colon impaction
- pelvic flexure
- sand impactions
- enteroliths (mineral calculus)
- cecal impaction
what is colitis
inflammatory disease of large intestine
colitis etiologies
- Infectious- Salmonella, Clostridium, Coronavirus, Potomac Horse Fever
- Verminous- encysted small strongyles
- Caustic- sand colitis
Nephrosplenic entrapment = _______Displacement
Left Dorsal
2 types of large colon displacements
Nephrosplenic entrapment (Left Dorsal)
Right Dorsal displacement
pelvic flexure
Ventral colon to dorsal colon, 180 degrees, narrows significantly
sand impactions
Accumulates in the ventral colon, right dorsal colon, pelvic flexure
enteroliths
mineral calculus
* California, alfalfa associated
* Typically in the right dorsal colon/transverse colon
cecal impaction
Primary but also important secondary condition
* Often associated with orthopedic surgical disease
colon volvulus
Severe, unrelenting abdominal pain
* Gross distension of the abdomen
* The volvulus is typically at the mesenteric attachment of the
colon to the dorsal body wall involving the cecum and entire large
colon
* Can twist just at the sternal/diaphragmatic flexure
issues of descending (small) colon
- Impaction/Fecoliths
- Salmonellosis
- Foals with meconium impactions
peritonisis
Unknown etiology
* Recent abdominal surgery
* Cyathostomiasis (small strongyles)
* Infiltrative bowel disease
* Internal abscesses
where are tapeworms found
- Ileocecal intussusception, cecocolic intussusception, typhilitis
Ascarids lead to…
Small intestinal impaction
strongyles are…
blood worms
where can strongyles be found
- Large colon - thromboembolic colic
Cranial mesenteric aneurysm
Strongylus vulgaris - Small- encysted cyathostomes
bacteria that causes a proliferative enteropathy
Lawsonia intracellularis
