Omasum - H2O absorption

Abomasum – True stomach, HCl, pepsinogen – see monogastric notes

 Small Intestine (enzymes from SI and Pancreas)

1. CHO – already digested and absorbed

2. Fats - fatty acids absorbed

3. Protein

Microbial and by-pass Protein ® amino acids

4. Minerals ® absorbed

5. Vitamins ® absorbed

Large Intestine = H2O absorption (minor mineral and H2O soluble vitamins)

 

Young Ruminants: Essentially monogastric – only abomasum is functional

3 weeks: Rumen begins to become fumctional

3 months: (4 mo.) fully functional

Esophageal Groove: muscle, during first 3-4 months of life active. Nursing stimulates it closing – milk by-passes rumen and goes into abomasum.

Terms

Regurgitate: to cast up "digested" feed to the mouth

Ruminate: Regurgitation, chewing, reswallowing

Eructate: Elimination of gas via belching

Gas produced by bacteria and protozoa

CO2 and CH4

Bloat = inability to expell gas

Swallow

Regurgitate

Chew bolus

Swallow

Another bolus regurgitated

 

Nonruminant Herbivore Digestion/Absorption

Mouth (see monogastric)

1. Food acquisition

2. Mechanical breakdown - mastication

3. Saliva

Esophagus - transportation

Stomach (see monogastric)

Small Intestine (enzymes from SI and Pancreas) – See Monogastric

Large Intestine

Cecum ~same as rumen, a pocket off of the LI

CP – already digested and Absorbed

Starch - already digested and Absorbed

Cellulose – VFA produced and some absorbed

B vitamins synthesized, but not absorbed in cecum

L.I. = H2O absorption (minor mineral and H2O soluble vitamins)

 

Pre-gastric VS. Post-gastric digestion of cellulose

 

Poultry Digestion/Absorption

Mouth (beak)

1. Food acquisition – no teeth

2. Poorly developed salivary gland

Esophagus - transportation

Crop – part of esophagus – ingesta holding and moistening, some species have a little fermentation

Proventriculus – ingesta passes through quickly

Gastric juice produced - HCl & pepsinogen

Ventriculus = Gizzard – very muscular to contract for physical ¯ particle size

Contains stones (grit) to assist in this physical breakdown

No enzymes, but HCl and pepsin from Proventriculus

Small Intestine – see monogastric

Enzymes ?? Lactase??

Ceca – 2 "cecums" – same as in horse, but not as extensively used

Large Intestine – see monogastric

Feces and urine (uric acid) are both excreted through same opening (vent)