Gut Microbiology and Fermentation

Why are microbes important

because they ferment fiber to compounds that can be used by the host

what are microbes made up of

short chain fatty acids (VFA+lactate)

how much energy do microbes make up in the body

makeup up to 75% of energy metabolized by host

where do microbes go after the rumen

to the small intestine and are digested by the host

how much protein are microbes made up of

made up of over 50% of protein metabolized by host

What are the 5 major groups of microbes

Bacteria

Protozoa

Fungi

Methanogens

Viruses

What percent of microbial mass is bacteria

90%

what are some characteristics of Bacteria

small(0.3 -50um)

ferment many diffrent substrates in feed

what are the diffrent substrates that bacteria ferment

-Fiber(cellulose,hemicellulose,pectin)

-Starch

-Sugar

-protein

-Amino Acids

-Lactate

what percent if microbial mass does ciliate protozoa make

3-50%

what is special about Cilate protozoa

they are predators of bacteria and other microbe

True/False: ciliate protozoa bigger than bacteria

True

why do protozoa eat bacteria

because it supplies them with protein, Nucleic acids,other factors need for growth

what is bad about protozoa eating bacteria( predation)

decreases flow of microbial protein to small intestine, so bad for the animal because bacteria gets eaten before they get to the small intestine decreasing protein intake for the animal.

what are the 2 types of protozoa that are microbes

Flagellete protozoa

-ciliate protozoa

what are Flagellete protozoa

-not abundant in microbes

unkown to eat bacteria possibly because of small size

what percentage of microbial mass is Fungi

arounf 0.5-8% of microbial mass

what are the 2 unique features of Fungi

-they have a complex life cycle

-**they ferment fiber**

True/False: Fungi dont contribute much to fermentation

True

how do Fungi start of there life cycle

as zoospores, which are free swimming

what is the first step of a Fungi life cycle

Zoopores attach and burrow into the cell walls

what is the second step of the Fungi life cycle

the Thallus which can not move develops in the cell wall

what does the thallus consist of

-Sporangium( contains future zoospores)

-Rhizoids (root-like structures that anchor the thallus)

what is the 3rd step of the Fungi life cycle

Mature sporangium erupts and releases new zoospores

what is the thing that fungi actaully ferment

Fiber specifically in plant cells

why is the details of Fiber fermentation by fungi so important

because the thallus (Rhizoids) penetrates deeply into cell walls and breaks them apart

what percentage does methanogens make of microbial mass

0.5-3%

what is a key product of methanogens

they produce methane

what domain do methanogens belong to

Archaea

What domain do Fungi and protozoa belong to

Eukaryota

True or False: all 3 domains of life are in the microbes of a ruminant

[[True ]]methanogens=Archea, bactera=bacteria, Fungi&protozoa=Eukaryota

what is another word for Viruses

Bacteriophages

what do viruses do Infect and lyse bacteria

In horses where do microbes grow

cecum and colon

what do the microbes in a horse do

ferment fiber to compounds that can be used by host

what makes up to 30% of energy metabolized by horses

Short chain fatty acids (VFA+lactate)

true or false: microbes do not grow in a horses stomach

False they do grow in the stomach

What is special about the microbes that grow in the stomach of the horse

they can only grow in the Upper part of the stomach because it is non-glandular with PH=5.8

what do the microbes in horses ferment

Ferment starch to lactate

why is fermentation of starch to lactate dangerous

because lactate can cause laminitis(leading cause of lameness) if horse given to much feed

what group of microbes is found in a horse stomach

Bacteria

what groups of microbes is found in caecum/colon

-bacteria

-methanogens

-fungi

-protozoa

also found in the rumen but at much higher concentrations

what fermentation happens in the stomach of a horse

lactate fermentation

What kind of fermentations happens in the cecum&colon

VFA(acetate,propionate,butyrate)

what is true about families and species in Ruminants and Horses

Groups are similar between teh 2 but family and species can differ

Do all animals have a git micrbiome

yes exception may be caterpillers

although all may have they have varying importance

what is the overall importance of microbes in animals

digest otherwise indigestible feed(fiber)

-convert fiber to short chain fatty acids

what percent of energy maintenance do microbes provide for Ruminants

30-80&

what percent of energy maintenance do microbes provide for humans

6-9%

what percent of energy maintenance do microbes provide for rabbits

6-38%

what percent of energy maintenance do microbes provide for horses

30%

how do microbes travel in an animal

they pass to the small intestine and are digested by the host BUT only of microbes are upstream of small intestine, otherways benefits get pooped out a lot (or if feces reingested by host {cropography})

Are microbes associated with disease explain

yes they are like obestity (can tranfer in mice), malnutrition,cancer

out of the 5 groups of microbes which are only found in some animals

-protozoa

-Fungi

True or False: gastrointestinal microbes account for most energy and protein avaliable to ruminant

True