Ruminants Flashcards
Which compartment of the ruminant stomach is the equivalent to the simple stomach?
Abomasum
Which part of the stomach has the inner surface raised into ridges?
Reticulum
What is the role of papillae in the rumen?
Increase SA for absorption of H2O, VFAs, ions
Which nerve regulated long reflex arcs in the neural plexus of the rumen?
Vagus nerve
What epithelial lining is present in the fore-stomach wall, why does this need to be protective?
Stratified squamous epithelium - keratinised
Roughage is very abrasive
What is the function of the omasum?
Functions as pump regulating outflow from rumen into abomasum
What is present in the omasum that helps with its function?
Long papillae that increase SA and contain smooth muscle so they can contract
What 3 components are secreted from the columnar epithelium lining the abomasum?
HCl
Pepsinogen
Rennin
Where do the most dense particles fall to in the stomach?
Reticulum
Where does gas from fermentation collect?
At the top of the dorsal sac
What are the 3 types of contraction in the rumino-reticulum?
Primary - mixing
Secondary - eructation
Rumination
What is the order of primary contractions during eating?
- First reticular contraction
- Second reticular contraction
- Cranial blind sac contraction
- Dorsal sac contraction
- Ventral sac contraction
What simulates rumination?
When coarse material stimulates oesophageal opening
How many minutes of rumination are required per Kg of roughage eaten?
60 mins
Where does newly swallowed material enter during rumination?
forced into dorsal sac and replaced by partially fermented material
What generates negative pressure in the oesophagus?
Thorax expansion
How do secondary contractions lead to eructation?
- occur every 2-3 primary contractions
- Oesophageal opening usually below level of gas hence gas can’t escape during rumination