Ruminant digestion Flashcards
What is the function of a ruminant’s complex stomach?
utilize CHO sources (cellulose)
produce food and other products using CHO
What is the progression of food through the digestive system of a ruminant (9 steps)
- mouth
- esophagus
- rumen
- reticulum
- omasum
- abomasum
- small intestine
- cecum
- large intestine
what is unique about ruminant dental anatomy
there are no upper teeth, they instead have a hard dental pad
what is the function of the mouth in ruminants
reduce particle size by teeth grinding
What are the two functions of saliva in ruminants?
- moisten food
- provide buffer for the rumen
name the three VFAs produced by the microorganisms in the rumen
- acetate
- proprionate
- butyrate
the esophagus in ruminants functions in ______
both directions for rumination
The rumen can make up ___% of the body weight of an animal
20%
compared to monogastrics, the abomasum can be considered ______
true or glandular stomach (lined with mucous membrane and producing gastric juice)
The rumen and reticulum can together be considered ______
the forestomach
What is the name for the type of tissue that lines the rumen and reticulum (forestomach)
stratified squamous epithelium
Does stratified squamous epithelium have any secretions?
no
What is the function of the rumen?
- act as the site of anaerobic and microbial fermentation
- absorption of fermentation end products (VFAs)
- store food (consuming large amounts to digest later)
What is the name of the shunt that allows milk to pass directly from the esophagus to the omasum?
esophageal or reticular groove
What do you know about the development of the rumen microbiome?
at birth, the rumen is sterile, and is partially developed by 4-6 weeks
The rumen is covered with ______ that help increase _______
papillae, surface area
the appearance of the papillae can change based on….
diet and season
What is distinct about the appearance of the reticulum?
it has a honeycomb pattern
What is the function of the reticulum?
- site of microbial action and absorption of VFAs
- the pacemaker for rumen contractions
the reticulum is where ____ can occur
rumination
What is rumination?
regurgitation, remastication, resalivation, and reglutition (reswallowing)
What is the appearance of the omasum?
long, pagelike lamina
What is the function of the omasum
the function is unclear - however some water and VFA absorption occurs, and some mechanical digestion occurs
it regulates particle size flowing from the abomasum to the SI
what are the secretions of the abomasum?
pepsin, HCl, and mucin
postgastric fermentation occurs in the ____
cecum and colon
5-15% of cellulytic digestion occurs ______
in the cecum and colon
What do you know about the ruminant large intestine?
any microbial protein made here is lost in feces, but VFAs can be absorbed through the large intestine
water is also absorbed here
Why is the rumen an ideal place for microbial growth? (9)
- warmth (101-105 degrees)
- moisture
- continuous inflow of nutrients via animal eating
- pH controlled (via saliva)
- no exposure to light
- mixing via digestive turbulence
- oxygen free (anaerobic environment)
- all end products are removed (absorbed or passed) preventing waste buildup
- small particle size due to rumination
the microorganisms and the rumen and the ruminant live in ______
symbiosis
Bacteria of the rumen
- digest cellulose, starch and proteins
protozoa of the rumen
prey on bacteria, 35 species
yeast of the rumen
not a large amount, aid in cellulose digestion