Lecture 56- Non-Ruminant Herbivore Digestive Physiology Flashcards
What does the ascending colon in a pig look like?
A spiral arrangement of coils in a cone shape
What does the ascending colon in a ruminant look like?
Arranged in spiral
What are the two type of fermenters?
- Pre-gastric fermenters
- Hindgut fermenters
What are the two classifications of pre-gastric fermenters?
Ruminants
->Femerling prior to gastric stomach and SI
Non-ruminant herbivores
->fermenting after gastric stomach and SI
What are two classifications of hindgut fermenters (non-ruminant herbivores)?
Cecal fermenters (rabbits, Guinea pigs, chinchillas, rat)
Colon federnderes (horses, gorillas, elephants, rhinos, koalas)
(TRUE/FALSE) Whether the animal ferments BEFORE and AFTER the gastric stomach and SI has a huge effect on efficiency of utilization of fermentation products
TRUE
*doesnt matter if animal ferments before or after
What are examples of non-ruminant herbivores?
Horse, rabbit, guinea pig, zebra, elephant, hippo, kangaroo
What are the THREE groups of non-ruminant herbivores? Which of these groups are hindgut fermenters?
Foregut fermenter
Cecal fermenter
Colon fermenter
*cecal fermenters and colon fermenters
Describe the modification that occurred to GIT to facilitate microbial fermentation?
Compartments of gastric stomach will selectively sort and retain fibrous material
Larger cecum and/or colon
When are the only two times fermentation is actually useful? If the digestive system can ….
- Retain digests and microbes
- Maintain an environment suitable for fermentation
What are three factors for utilizing microbial fermentation?
- Volume available for fermentation—greatest in ruminants
- Retention time (longer retention=more digesta)
- Microbial populations similar in most species
What type of stomach do foregut fermenters have?
Compartmentalized stomach
*one or more pouches for fermentation separate from gastric region—“pre-gastric” fermentation
How many pouches does a compartmentalized stomach have?
2-4 pouches
Which region expands for microbial fermentation?
Cardiac region
What type of feeders are foregut fermenters?
Bulk roughage feeders or browsers
Are any of the non-ruminant herbivore domesticated species foregut fermenters?
None
How many pouches does a colobus monkey have?
4 pouches/chambers
How many pouches/chambers do sloths have?
3 chambers/pouches
What are two species that are Cecal fermenters?
Rodents and lagomorphs
The cecum is a ______ sac, therefore digesta must pass via _____ of ____.
Blind
route entry
How many times do Cecal contents enter the colon?
1-2 times/day
How are particles separated in the colon?
-less dense material (larger fiber particles) stay in lumen
-denser, smaller particles + fluid around perimeter
-fiber particles move through colon
-fluid + smaller particles -> go into cecum for fermentation
What are the two types of feces that cecal fermenters produce?
Hard feces -> indigestible feces
Soft feces (night feces) -> ceotropes are cecal contents coated with mucus and are consumed-> added B-vitamins made by microbial patterns
Which three species are colon fermenters?
Equips, elephants, koalas
Why is hindgut fermentation less efficient?
The anatomical location makes there less opportunity and ability to absorb products fermentation and utilize microbial protein
Why is hindgut fermentation superior to ruminants fermentation for low quality forages?
*hindgut fermentation—digestion moves through faster, animal increases intake of feed
*ruminants low quality forage “hangs out” in lumen for a long time
Where is the primary site of microbial fermentation and digestion of cellulose?
Hindgut
What does the mixing of contents in the hingut promote?
Promote fermentation and expose contents to mucosa for absorption of VFAs
What does the ileum and colonic epithelium secrete?
Bicarbonate
When the ileum and colonic epithelium secrete bicarbonate what happens?
Buffer pH of VFA produced
What VFA products of?
Fermentation
What are VFA used for?
Energy
What contributes to motility in the cecum?
Haustrae contacting and expanding
What contributes to motility in the ascending colon?
Segmentation and haustral contractions
What is the transit rate in the colon?
2-3 days
Large quantities of ________ produced and absorbed, but ___________ _________ wasted.
VFAs
Microbial patterns
