4 Rumen Fermentation

4 Rumen Fermentation - Rumen Fermentation RumenFermentation...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
Rumen  Fermentation
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Rumen Fermentation World’s largest  commercial  fermentation space 100 billion liters or  rumen volume in  domestic animals 10 10  to 10 12  cells/mL Rumen capacity ranges  from less than 1 liter (1  quart) in a duiker to 200  liters (50 gallons) in a  cow
Background image of page 2
Ruminants Continuous culture fermenters Input and output Lignocellulosic substrates (forages)  digested Cellulase complex Hemicellulases Nitrogen capture (NPN) 8 x 10 15  mouths to feed Because of these microbial enzymes, ruminants can utilize feedstuffs that provide little to no nutritional benefit to non-ruminants
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Four Steps of Rumination Regurgitation Reverse peristalsis carries food to mouth Remastication Liquid squeezed from bolus and  swallowed Bolus chewed Reinsalivation Adding more saliva Redeglutition Swallowing bolus and liquids
Background image of page 4
Rumination Allows animal to forage and eat food rapidly,  and then store for later digestion Reduces particle size Only small particles leave reticulorumen Increases surface area for microbial  attachment and digestion/fermentation Breaks down impervious plant walls Further stimulation of saliva flow (saliva serves  to buffer rumen)
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Rumination Time Average times for a grazing animal Eating – 8 hours Ruminating – 8 hours Resting – 8 hours Ruminating time is quite variable (high  variation) Reducing forage:concentrate decreases rumination Reducing particle size of forage decreases time  spent ruminating
Background image of page 6
Mechanism of Rumination: Regurgitation Stimulus – digesta in fiber mat scratching surface  near cardiac sphincter Contraction of the reticulum forces digesta to cardia Animal inhales with epiglottis closed to produce a  vacuum Cardia sphincter opens and esophagus dilates Negative pressure (vacuum) sucks digesta into esophagus Rapid reverse peristalsis moves digesta to mouth
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mechanism of Rumination: Remastication,  Reinsalivation, and Redeglutition Bolus is rechewed Chewing is slower and more deliberate than during  initial eating phase Digesta reinsalivated Parotid glands secrete more saliva during rumination  than eating Saliva from parotid glands secrete more NaHCO 3 -  than  other glands Reswallowing After reswallowing, the rumen contracts to move  swallowed bolus into the rumen
Background image of page 8
Remastication  and Redeglutition
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Ingested Feeds Chewing during eating (minimal) Preparation for swallowing Release soluble constituents Damage plant tissues for microbial attachment Chewing during remastication (extensive) Decrease particle size for passage Damage plant tissues for microbial attachment Microbial digestion Reticuloruminal contractions
Background image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 47

4 Rumen Fermentation - Rumen Fermentation RumenFermentation...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online