Ruminant Digestion Flashcards
how many domesticated ruminants in the world
2.8 billion
pregasttic fermentation
ability to chew cud @ frequent intervals
stomachs
reticulum
rumen
omasum
abomasum
ruminare
cud chewing, even toed hooves mammals
tylopoda
even toed with fleshy pads rather than hooves
feeding strategies
bulk and roughage eaters grasers- cows
concentrate selectors (browser)-deer
intermediate feeders- sheep, goats
concrete selectors-
select a diet rich in easily digestible plant parts. lower capacity to digest cell walls eats small amounts frequently
intermediate feeders-
vary diet between grazing or browsing seasonally adaptive
upper tooth cheek is in contact with two lower cheek teeth
true
salvia
submaxillary, sublingual, parotid
how much does a sheep saliva produce per day
7 L/D
how much does a cow saliva produce per day
150 L/d
is there digestive enzymes in the salvia of mature ruminants?
no
what elements are present I saliva
N,P,S Na
esophagus
different from monogatstricsc
striated muscle along the entire length
provides greater strength
funnel shaped
inner mucosa
lined with stratified (several layers) squamous (flattened) epithelium
protective in nature
flexible can stretch
no absorption from oesophagus
can lubrication
outer muscular tunic
striated muscle
food movesby peristaltic contractions
NB in rumination negative pressure
when is rumen fully developed
3 months
% rumen VS abomasum when could is born
30% VS 70%
% Rumen VS abomasum when cow is mature?
7% 80%
rumen
large anaerobic fermentation vat
rumen capacity
cow- normal 25-30 gallons MAX 55-60 gallons
ewe-Normal 3-5 gallons MAX 5-10 gallons
Temperature - 38-42
VFA Ratio- 70;20;10
acetate; propionate; butyrate
protozoa-
bacteria/fungi
100,000/gram of rumen fluid
100 million/gram of rumen fluid
functions of microorganisms-
digest roughages to make VFA, make microbial protein and make vitamins K and B complex
where are VFA absorbed?
in the rumen
VFA
Acetic acid
Propionic acid
butyric acid
high concentration diet
more propionate
high forge diet
more acetate
how long does rumination occupy their day
1/3
eructation (belching) production per hour cattle sheep
30-50 litres per hour
5-7 L/hour
belching allows ruminants to get rid of fermentation gases.
bloating can cause death from asphyxiation (death as a result of lack of o2)
how many times more potent is methane than C02
27X
AG accounts for X% if total Irish GHG emissions
37%
enteric methane accounts for approx x% total Irish ag emissions
60%
reticulum
honeycomb lining
regurgitation initiated here
collects hardware ( nails, wire etc)
omasum
heavy hard organ with lining that has many folds
believed to produce a grinding action on foodstuff
absorption of water 〰60% removed
abomasum (true gastric stomach)
cardiac, fundric, pyloric
ph decreases 6-2.5
denatures proteins
kills bacteria
dissolves minerals
*** unique feature secrets Lysozyme
lysozyme
secreted by the abomasum
enzymes that breaks down bacterial cell walls
needed to breakdown large amounts of bacteria that pass from the rumen
Pancreatic secretions
2.2-4.8 L/day (cattle )
0.3-0.4 L/day (Sheep)
secretion Ph- 7.2-7.8
LI- Digestion in colon may account for as much as X% Cellulose
X% hemicellulose
X% starch
27%
40%
10%
the faster the rate of digestion the quicker the rumen is emptied
= increase in feed intake
reduced digestiliby
= increased Ph
how many methanogens are identified
30 species
Fungi
strictly anaerobic and their lifecycle includes a motile phase (zoospore) negative phases ( sporangium)
Animals cant digest XXX so microbes do it
B-Linked polysaccharides and non protein nitrogen
