Rabbit GI anatomy and physiology Flashcards
Name the rabbit salivary glands (and if you upgrade to PRO, add a picture to label)
Sublingual
buccal
Parotid
mandibular
What percentage of the GIT volume is the stomach?
15%
What does the ampulla (just past the pylorus) do?
AKA ampulla of Vater. It’s where the pancreatic/common bile ducts empty.
what is the sphincter of Oddi?
muscle that controls secretion from the pancreatic/common bile ducts into the ampulla
How fast do rabbit incisors grow?
up to 2 mm/wk
Basic function of the colon?
separates first-pass fibers into nondigestible (to be pooped out) and digestible (to stay as a substrate for fermentation, mostly in the cecum. also reabsorbs water and makes poop.
Do rabbits see their food as they eat it?
nope, they select food & textures via vibrissae & taste etc. Prey eyes.
How many teeth do rabbits have and what are they for?
28 total
6 incisors (2 real upper, 2 peg teeth upper, 2 lower): to slice food
22 PM/Ms: grind the food.
what are normal pH ranges in rabbits
Pre-weaning: 5.0-6.5 (helps establish flora)
Post weaning, eating first pass food: 1.0-2.0 (Jesus)
Post weaning, eating a cecotrope: 3.0
Normal GI transit time in a rabbit?
3-6 hours for first pass
Main function of duodenum?
Mix in bicarb and digestive enzymes (esp to cecotropes)
Main functions of jejunum & ileum?
Actual absorption of nutrients from the cecotrophs; some bacterial fermentation occurs in the ileum as well.
What’s the thingy between the ileum and the colon?
ileocolic valve - reduces reflux from lower GIT to upper
General transit time of the small intestines?
10-20 min in jejunum, 30-60 min in ileum
Where are the gut-associated lymphoid tissues found in rabbits?
Peyer’s patches (Jejunum & distal ileum)
Sacculus rotundus at the ICJ
Vermiform appendix (distal cecum)
Lymphoid follicles along the colon
which organ makes up 49% (but not 50%, that would apparently be way too much) of the GIT volume
seekum you shall findum
but takes up >50% of abdominal volume. how the hell does that math work either??
Twisty coils on the right side, huge, thin walled
Is a cecum!
what’s at the end of the cecal rainbow?
The vermiform appendix (secretes bicarb and makes immune cells)
What are the 4 regions of the rabbit colon?
1) Anterior part 1: about 10 cm. 3 taeniae, 3 haustrae
2) Anterior 2: about 20 cm. 1 ea taenia/haustra
3) Fusus coli
4) Distal colon: 80-100 cm long, no t/h, short crypts, many goblet cells
what’s the function of the fusus coli and where is it
3rd region of the rabbit colon, 4 cm band of muscle & innervation, controls pass-through of multiple areas of large intestine. Lots of goblet cells, which package up cecotrophs in mucus and squish them down.
describe how particles move through the cecum and colon (ideally with picture/Pro)
homogenous first-pass schmoo goes from ileum and get spread evently between cecum and colon. Cecum moves stuff over to the colon, which divides it into save vs poop. Save gets refluxed to the cecum to ferment. Cecum has different contractions for cecotrope vs excrete.
what plant fibers can the cecal microbes ferment?
mostly cellulose, pectin, and hemicellulose; last 2 are more important
what are the main products of cecal fermentation and where do they go?
volatile fatty acids - 75% acetate, 10% propionate, 15% butyrate.
Butyrate: feeds the colon
Others: bloodstream, go to liver & get made into other things there.
Overall this is 30% of the rabbit’s metabolic needs!
How does the fusus coli affect cecotropes?
1) secretes prostaglandins to STOP haustral contractions and START distal cecal contractions
2) cecotrope goes FWOOSH down the cecum, prox colon
3) Fusus coli goblet cells package it in mucus and squish it into shape
4) Colon goes PEW PEW PEW