Forestomach and Fermentation Digestion

What is the triad of animal production?

Genetics

Nutrition

Health

What is a Feed Conversion Ratio?

How much an animal needs to eat to produce a certain output

FCR is going to be affected by?

Genetics,

Age

Feed environment

Forestomach fermenters thrive on ____ and hind gut fermenters need ____?

Low quality

High quality and more frequent feedings

Foregut fermenters have an enlarged _____ where as hindgut fermenters have an enlarged ____?

Stomach/ rumen

Colon

Most of fermentation of a foregut animal takes place in the?

Rumen and reticulum

Where is h20 absorbed in the ruminant?

Omasum

What part of the ruminant stomach is most similar to a mono gastric animal (glandular)?

Abomasum

____ and ___ carbohydrates can be digested by both microbial and animal enzymes but ___ can only be digested by microbes?

Starch and sugars

Fibers

Fibers are ____ of plants and include what kinds of carbohydrates?

Cell walls

-Cellulose

-Hemicellulose

-Pectin

-Lignin

What enzyme do only microbes have?

Cellulase - breaks the B 1-4glycocidic bonds

Plants have very little ____ and most of it is digested by the microbes?

Proteins

Is fat an important part of a ruminant diet?

No, microbes will help digest

What two things do microbes provide nutrition wise for the ruminant?

Energetic molecules - Volatile fatty acids

Microbial biomass - proteins from break down of microbes

Fermentation occurs ___ where as glandular and luminal digestion occurs ___?

Slowly

Fast

Fermentation is an ____ process to break down carbohydrates?

Anaerobic

What is the rate of fermentation?

Sugar < starch < fibers

What is the reticulo-omasal orifice?

A sphincter that only allows liquid and small particles through to control retention time for fermentation

Why is it important that foregut fermenters, ruminate before reaching the glandular stomach?

Allows them to get protein from digested microbes

Foregut fermentation occurs in the ___ and ___

Hindgut fermentation occurs in the ____ and __?

Rumen & Reticulum

Cecum & colon

What factors create the rumen environment?

Temp

pH (more basic)

Redox potential - no O2 available

Osmolarity

Gas phase

Anaerobiosis will force the microbes to produce what?

Energetic wastes for the benefits of the host

What do microorganisms use to make protein?

Non-protein nitrogen like urea and ammonia

What kind of bacteria will produce lactic acid and VFA?

Amylolytic bacteria

What is a concern of fast growing Amylolytic bacteria?

Can lower rumen pH leading to acidosis and killing celluolytic bacteria bacteria

What bacteria can help correct acidosis in the rumen?

Lactate degrading bacteria metabolize lactic acid and keep pH under control

What kind of bacteria will remove excess H2 which is toxic to fermentation rxns and make CH4?

Ruminal Archaea/ methanogens

Why would having facultative anaerobes in the rumen be important?

Consums any o2 that may appear to contribute to anaerobiosis

What is the main functions of rumen protozoa?

Fiber digestion of cellulose and pectin to decrease the risk of acidosis

What are some ways protozoa reduce acidosis?

Ingest bacteria,

degrade protein (increase food sorce for bacteria)

Consume lactic acid

What are the two types of Rumen fungi?

Parasitization of ciliate protozoa

Saprophytic on plant tissue

Why are viruses important in the rumen?

Parasitize bacteria

Lysing bacteria to increase protein available

How does an animal get vit B?

Microbial synthesis (microbes feed on vit B in cross feeding mechanism)

When does microbial competition occur?

Available substrate

Energy requirements

Resistance to inhibitory substance other microbes produce

Ability to attach to plant cell and hydrolyze cell wall

Hydorlysis is an _____ process?

Extracellular

Microbes that can't live on hydrolysis or fermentation of other species will do what?

Predate on other microbes in the rumen

What two byproducts can microbes use?

VFA and NH3

Rapid break down of proteinaceous feeds feeds can lead to what?

Excessive production of ammonia

Grains are ___ in starches and ____ in fiber

Roughage is ____ in starches and ____ in fibers?

High, low

Low, high

(balance is needed for proper rumen health)

What is generation time?

the time it takes for a population to double

Microbial cells grow in a _____ phase for long periods due to what?

Exponential phases

-feed input

-waste removal

-Mixing movements

-washout

If we have a High C:N ratio we will see a _____?

If we have a low C:N ratio we will see a ___?

Nitrogen shorted w/ limited microbial growth

Ammonia build up which is toxic

What is dilution rate?

Speed of rumen content washout

____ bacteria in the rumen is best?

Young

Explain nitrogen flow of ruminants?

Ruminants save nitrogen as urea and during starvation muscle is broken down to AA to feed microbes.

Microbes will make AA using NH3 and keto acids

Excess luminal urea/NH3 goes to blood to the liver to be converted to urea