Anatomy of LI in exotics Flashcards
What is the function of the proximal colon in rabbits?
separates ingesta based on particle size
What are the 2 types of faecal pellets produced by rabbits and how are they produced?
Large particles: indigestible fibre => down colon, eliminated quickly => HARD DRY PELLETS
Smaller particles, fluids: retrograde peristalsis => caecum, microbial fermentation => CAECOTROPHS
where in the rabbit GIT is there a high conc of GALT?
sacculus rotundus (caecal tonsil)
Appendix
what is the ampulla caecalis coli in rabbits?
T junction between ileum, caecum and proximal colon
Separates particles based on size
What is the function of the appendix in rabbits?
GALT
bicarbonate ions buffer VFAs from microbial fermentation
Describe the anatomy of the proximal colon in rabbits
Haustra/sacculations - increases SA
Warzen - protrusion on the mucosal surface
Taeniae
Fuses coli (base of proximal colon)
What is the function of warzen in the rabbit proximal colon
increases SA for absorption
What is the function of haustra in rabbit proximal colon?
small particles that leak into proximal colon can settle and then be pushed back into caecum
What is the difference in anatomy between the cranial and caudal sections of the rabbit proximal colon?
What is the function of the fusus coli of the rabbit proximal colon?
innervated
muscular
goblet cells - produces mucous
Label rabbit GIT
Describe the conditions in the rabbit caecum
Fine balance of bacteria, protozoa and yeasts
changes based on: time of day, age, diet, pH
Fermentation produces ammonia, VFAs, amino acids, water-soluble vitamins
Buffered by bicarbonate ions (from appendix) and dietary fibre
Describe the hard faeces phase of hindgut motility in rabbits
During feeding
small particles -> haustra -> caecum
Water -> proximal colon
Caecal contractility greatest
Fuses coli squeezes out water
Distal colon reabsorbs water, K, Na, VFAs
Dry indigestible matter expelled - HARD FAECAL PELLETS
Describe the soft faeces phase of hindgut motility in rabbits
Occurs at rest
Caecotrophs produced
decreased motility of caecum and proximal colon
increased motility of distal colon
Caecal material -> large colon
Fusus coli forms pellets, adds mucous (makes nicer to eat)
Rapid excretion of caecotrophs
Describe the contents of rabbit caecotrophs
Soft paste: protein, AAs, vitamins, minerals
Mucous, encapsulates pellets
Lysozyme
What is the function of lysozyme in rabbit caecotrophs
Digests bacterial cell walls allowing rabbit to access the protein in bacteria
What is the function of the fusus coli in rabbits?
Pacemaker:
- initiates peristaltic waves in colon
- highly innervated
- hormonal influence (aldosterone and prostaglandins)
What is the effect of fibre, fat, protein and carbs to motility and caecotrophy in rabbits
Fibre:
- good
- stimulates hindgut motility, buffer for VFAs
- increased caecotrophs
Fat:
- good
- increase motility
- energy source
Protein:
- bad
- decreased caecotrophs
Carbohydrate:
- bad
- glucose -> excess VFAs
- enterotoxaemia
What is the dental formulae of guinea pigs and chinchillas?
Describe guinea pig and chinchilla dentition
Open rooted teeth, grow throughout life
Describe guinea pig GIT?
long caecum
cannot make vitamin C - dietary source essential - leafy greens, Vit C tablets/syrup
produce caecotrophs
Describe the palatal ostium in guinea pigs and chinchillas
Soft palate continuous with tongue
Membranous covering posterior pharynx
Palatal ostium = hole in membrane
Careful during intubation
Describe chinchilla GIT
long GIT:
- large coiled caecum
- colon highly sacculated
Produce caecotrophs
What is the dental formulae of small rodents
Describe small rodent dentition
Only incisors open-rooted, lower incisors longer
Describe small rodent digestion
hindgut- fermenting monogastric herbivores
Produce caecotrophs
Describe the unique anatomy of hamster stomachs
Pre-gastric pouch for pre-gastric fermentation (high pH)
Describe the GIT of ferrets
simple stomach
short SI - poor nutrient absorption
no caecum or appendix
simple GI flora
rapid transmit time
Describe ferret diet
obligate carnivores
high quality, highly digestible, well balanced, meat based diet
Main energy source = fat
NEVER CARBS - prone to insulinoma => hypoglycaemia
Who is your best friend
Bernie obviously
