Rumen and stomach microbiology Flashcards
What does microbial fermentation provide?
High quality protein from poor material
Incorporate nitrogen from non-nitrogen sources into proteins to make them available for the animal (incorporates urea)
Incorporating hard to digest carbon into microbial proteins
Essential amino acids
Vitamin B
What conditions are required for a stable microbial population in the rumen?
Nutrients - consistent eating
pH - VFA production, buffered by phosphate bicarbonate from saliva
Temp
Redox - oxygen enters with food, soaked up by bacteria to maintain anaerobic conditions
What type of microbes digest grass/hay?
cellulytic microbes
What are some common protozoa found in the rumen?
Holotrichs
oliogotrichs
What is the function of anaerobic fungi in the rumen?
colonise plant fragments
actively ferment cellulose and soluble sugars
may help break up plant fibres
What is the possible effect of changing diet on the microflora of the rumen?
If bacteria gain a new, easier source of nutrition it will switch its metabolism to use that and may outgrow an disrupt the balance of bacteria
If feed is altered quickly some bacteria may lose a good source of nutrition and slow down
Can lead to altered metabolite production
How can altering diet lead to acidosis in ruminants
Changing the diet to give accessible carbs e.g., starchy food, can lead to rapid production of VFAs => acidosis
Why are oral antibiotics not given to adult ruminants?
they can disrupt rumen function
Describe the features of helicobacter species (bacteria)
helical/vibrio shape
gram -ve
How does helicobacter survive in the monogastric stomach
Drills into mucous gel layers
binds to membrane-associated lipids of epithelial cells
Secretes large amounts of urease
urease metabolises urea to produce ammonia
ammonia neutralises gastric acid
What tests can be used to test for helicobacter?
blood antibody test
stool antigen test
carbon urea breath test
