Ruminant Anatomy and Physiology Flashcards
Differentiate between the primary and secondary mixing cycle
- Primary mixing is initiated by the reticulum, pushes stuff into the caudodorsal blind sac of the rumen
- Secondary mixing is responsible for eructation, starts in the caudodorsal blind sac of the rumen, forces gas to the cardia
Describe the anatomy and function of the rumen
- Fermentation
- Nutrient absorption (papillae absorb VFAs and ammonia)
- Synthesis of proteins and B vitamins
- Gas expulsion (Eructation)
Anatomy: On the LEFT side, Caudodorsal blind sac is palpable on rectal exam
Describe the anatomy and function of the omasum
- Water absorption
Anatomy: leaf like folds, butchers bible
Describe methods of rumen juice collection
- Ororuminal collection
- Rumenocentesis
- Rumen fistula
NB: Rumen pH will be affected by saliva pH with Ororuminal collection, do the others if measuring pH
List techniques used to analyze rumen juice
- pH
- Methylene blue reduction test
- Glucose fermentation test
- Nitrate reduction test
- Cellulose reduction test
- Rumen Cl- levels
- Sedimentation test
- Microscopic exam
- Color, consistency, odor
Describe the purpose of the methylene blue reduction test
- Looks at anaerobic bacT fermentation
- If > 10 mins to turn from blue to clear = Rumen acidosis or Indigestible roughage
- Transfaunation indicated if > 10 mins
(normal is 2-6 mins)
Describe the purpose of the cellulose digestion test
- Looks at digestion of fibers
- Takes a long time, not accurate
Describe the purpose of the glucose fermentation test
- Looks at digestion of glucose
- Little to no gas = inactive microflora
Describe the purpose of the nitrate reduction test
- Looks at digestion of proteins by microbes
When are cows considered a true ruminant?
6 weeks - when the esophageal groove closes
What stimulates papillae growth in the rumen?
Stimulated by VFAs (Butyrate and Proprionate)
- Milk AND Grain is best
What is the function of the esophageal groove?
- Remains open until 6 weeks old
- Allows milk to bypass the forestomachs and enter straight into abomasum
What occurs with failure of the esophageal groove to close?
- Rumen Putrefaction “Rumen Drinkers”
- Results in milk entering into forestomachs
- Curdling milk found in the rumen and reticulum
VFA production is highest with which type of diet?
- Higher VFAs with high fiber diet
- Little VFAs with high starch (grain) (Except higher proprionate with grain)
What VFA is the primary source of glucose for ruminants?
Proprionate
What is the normal time of rumination for cows?
- 10 hrs a day for high forage diets
- Little to none if on grain
- Cows chew cud while laying down
The fecal occult test has a ______ specificity and a _____ sensitivity. When would you believe the result?
high, low
trust a positive result
___________ is the process of transferring healthy rumen content to a sick animal
Transfaunation
What color would the rumen fluid be with lactic acidosis?
milky grey/brown
What color and consistency would the rumen fluid be with abomasal reflux in calves?
Grey with clots of milk
What causes rumen fluid to have an almond odor?
- Abomasal issue
What does no sedimentation mean when performing this test on rumen fluid?
- Frothy bloat or Vagal indigestion
(normal sedimentation is 4-8 mins)
What does elevated Cl- from rumen fluid indicate?
- Abomasal disease
- Abomasal reflux
- Obstruction of intestinal outflow
- Normal Cl- of rumen: 15-30
(HCL from abomasum backflow into rumen)
What is the Liptak test used for?
- To confirm a displaced abomasum
- Collect fluid from where “ping” was heard, if pH <4.5 and Almond odor, confirms abomasum
