Story on What You Sow Is What You Reap
Ruminant Digestive System
Complex structure with four compartments
Source: Animal Feeding and Nutrition (Jurgens)
Ruminant Characteristics
Primarily herbivores
Cattle, sheep, goats, deer, elk Camelids are “pseodu” ruminants
60-75% of ingesta fermented by microbes before exposed to gastric juices
Mouth
Tongue
Used more by cattle and goats (also use lips)
Teeth
No upper incisors Used more by sheep (use lips to “sort” feed)
Saliva
Continual production Cattle: 12 gal/d vs Sheep: 2 gal/d No enzymes; High pH
Esophagus
No sphincter valve Opens into reticulum and rumen Muscle contractions move in both directions
Stomach compartments
Reticulum Rumen Omasum Abomasum
A higher proportion of a ruminant’s digestive system is stomach
Reticulum characteristics
Located next to heart Honeycomb appearance
Catches metal and hardware
Pathways
Esophagus Rumen Omasum
No enzymes secreted
Rumen Characteristics
Left side of abdomen Papillae lining Muscular pillars Fermentation vat
Primarily anaerobic Some aerobic microbes
Not functional at birth
Rumen Functions
Storage Soaking Physical mixing and breakdown Fermentation
Synthesizes some vitamins Synthesizes AA and protein Breaks down fibrous feeds into VFAs
Volatile Fatty Acids (VFAs)
Acetic Acid Butyric Acid Propionic Acid
Omasum
“Manyplies” No enzymes from walls Function
Reduce particle size Absorb some water
Abomasum
“True stomach” that secretes enzymes from walls Glandular stomach like monogastric fundic region
HCL, Mucin Pepsinogen, Rennin and Lipase
Small and Large Intestine
Same SI sections
Duodenum, Jejunum and Ilium
Same LI sections
Cecum, Colon and Rectum
Ruminant Differences
Esophageal Groove
By passes reticulum and rumen in young animals
Rumination
Chew their cud (food bolus) Up to 8 hours/day
⌧Decrease particle size for microbes ⌧Increases saliva production to buffer rumen
About 30 times/day
Ruminant Differences con’t
Eructation (belching)
CO2 and Methane Produced by microbial population in
Complex structure with four compartments
Source: Animal Feeding and Nutrition (Jurgens)
Ruminant Characteristics
Primarily herbivores
Cattle, sheep, goats, deer, elk Camelids are “pseodu” ruminants
60-75% of ingesta fermented by microbes before exposed to gastric juices
Mouth
Tongue
Used more by cattle and goats (also use lips)
Teeth
No upper incisors Used more by sheep (use lips to “sort” feed)
Saliva
Continual production Cattle: 12 gal/d vs Sheep: 2 gal/d No enzymes; High pH
Esophagus
No sphincter valve Opens into reticulum and rumen Muscle contractions move in both directions
Stomach compartments
Reticulum Rumen Omasum Abomasum
A higher proportion of a ruminant’s digestive system is stomach
Reticulum characteristics
Located next to heart Honeycomb appearance
Catches metal and hardware
Pathways
Esophagus Rumen Omasum
No enzymes secreted
Rumen Characteristics
Left side of abdomen Papillae lining Muscular pillars Fermentation vat
Primarily anaerobic Some aerobic microbes
Not functional at birth
Rumen Functions
Storage Soaking Physical mixing and breakdown Fermentation
Synthesizes some vitamins Synthesizes AA and protein Breaks down fibrous feeds into VFAs
Volatile Fatty Acids (VFAs)
Acetic Acid Butyric Acid Propionic Acid
Omasum
“Manyplies” No enzymes from walls Function
Reduce particle size Absorb some water
Abomasum
“True stomach” that secretes enzymes from walls Glandular stomach like monogastric fundic region
HCL, Mucin Pepsinogen, Rennin and Lipase
Small and Large Intestine
Same SI sections
Duodenum, Jejunum and Ilium
Same LI sections
Cecum, Colon and Rectum
Ruminant Differences
Esophageal Groove
By passes reticulum and rumen in young animals
Rumination
Chew their cud (food bolus) Up to 8 hours/day
⌧Decrease particle size for microbes ⌧Increases saliva production to buffer rumen
About 30 times/day
Ruminant Differences con’t
Eructation (belching)
CO2 and Methane Produced by microbial population in