Cows A11- A19 Flashcards
pH of rumen
6.5
what maintains the pH of the rumen
saliva
quantity of saliva produced each day
20L/day
function of saliva
acts as a buffer
what does saliva contain
HCO3
HPO4^2-
what happens in case of low chewing
decreased saliva
decreased buffer capacity
acidosis
structural carbohydrates feed types
hay/roughage
non structural carbohydrates feed types
cereals
nutrients of structural carbohydrates
cellulose
hemicellulose
pectin
nutrients of non structural carbohydrates
starch
fructose
sucrose
degradation of cellulose and hemicellulose
occurs at pH6-7
cellulose and hemicellulose degrade into
acetic acid
succinate
ethanol
formic acid
CO2
H2
pectin degrades into
VFA
lactic acid
succinate
starch and sugar are degraded by
streptococcus bovis
starch and sugar degrade into
lactic acid
acetic acid
proprionic acid
succinate
ethanol
sugar is degraded by
protozoa
sugar degrades into
acetate
butyrate
H2
succinate fermentive bacteria
co2
proprionic acid
what type of enzymes does bacteria in the rumen produce
extracellular enzymes
what do EC enzymes do
polysaccharides —> pyruvate
what do IC enzymes do
pyruvate –> VFA and ATP
quantity of VFA produced
3-4kg/day
3 VFA
acetate
propionate
butyrate
what does acetate break down to
AcCoa –> fat or ketone bodies
consequence of increasing roughage on acetate
increases therefore decreases amylitic bacteria and increasing cellulocytic bacteria
what does propionate break down to
energy
GNG producing glucose
what does butyrate break down to
energy
ketones
CP of ruminants
total N x 6.25 (true protein & NPN)
first step of protein degradation
to peptides by bacterial protease
second step of protein degradation
peptides to amino acids by peptidase
3rd step of protein degradation
amino acids to NH3, CO2, VFA by deamination
how is urea degraded
to NH3 by urease
What type of protein does a cow eat
CP
in the cow what happens to UDP
UDP + microbial protein –> amino acids to tissues and mammary glands
in the cow what are the 3 protein types
UDP
NPN
RDP
in the cow what happens to NPN
NPN –> NH3
NH3 becomes either energy or microbial protein
in the cow what happens RDP
RDP –> NH3
the 2 protein requirements of Ru
MPN
MPE
what is MP
metabolizable protein
the amino acids available in the small intestine
UDP + microbial protein
MPN
nitrogen dependant metabolisable protein
MPE
energy dependant metabolisable protein
how to increase UDP in feed
heat protein
formaldehyde treatment
maillard reaction
capping
function of capping
provides a lipid layer around methionine to prevent ruminal breakdown
function of formaldehyde treatment
binds to free amino acids which decompose in the intestines
function of maillard reaction
degradation of connection between proteins and carbs
foods with high RDP
cereals, not maize
field bean
soybean
grass hay
grass haylage
foods with medium RDP
maize
peas
sunflower meal
rapeseed
silomaize
fresh grass
foods with low RDP
sorghum
maize gluten
fish meal
pelleted alfalfa
what concentrate helps ammonia and energy curves meet
molasses
UFP definition
urea fermentation potential
how much urea is in 1kg DM
UFP equation -ew
(1.044TDN – degradation of protein) / 2.8
factors influencing ruminal degradation of feed proteins
protein degrading activity of rumen microbes
protein structure
sources of protein in the small intestine
By pass protein
protein synthesized in rumen
endogenous protein
utilisation of RDP
90%
utilisation of NPN
80%
requirement of by pass soybean protein
0.5-1kg
requirement of by pass methionine
10-20g/day
what feed type would you find simple fats?
seeds
what feed type would you find composed lipids
roughages
what type of fat is simple
triglyceride
what type of fat is composed
phospholipid
galactolipid
types of lipids in the diet
triglyceride
phospholipid
galactolipid
first step of lipid degradation
by bacterial lipase to glycerol & galactose and FA
linolenic acid hydrogenisation
linolenic acid + H+ –> stearic acid
linoleic acid hydrogenisation
linoleic acid + H+ –> oleic acid
how does an unsaturated fat become saturated
hydrogenised in the rumen
what type of fats do green forages have
unsat
as they spend less time in the rumen
if dairy cow needs more energy
dont give concentrates
why not give concentrates to dairy cow if they need more energy
decreased chewing
decreased saliva
increased VFA
acidosis
if dairy cow needs more energy give
more fats
5-8% DM
function of fat in rumen
dissolve fats and surround fibres
therefore no access for enzyme microbial digestion
decreasing acetate
lipid supplementation in the diet
(3)
ether extract
plant origin feedstuff
by pass fat
ether extract content of diet
2.5-3%
plant origin feedstuffs
2-3%
protected or bypass fats
2-3%
total lipid supplementation
5-8%
1.2-1.5kg
feed additives
yeast
buffer
main product of beef
offspring
main product of dairy cows
mother’s milk is main product
bw of calves at birth
40-50kg
bw of calves at 3months
80-110kg
bw of calves at 6 months
180-200kg
ruminoreticulum abomasum ratio at 1 month
0.5
ruminoreticulum abomasum ratio at 2 months
1.5
ruminoreticulum abomasum ratio at 4 months
4.5
feeding of calf from day 0 - week 1
8-10L/ day colostrum
feeding of calf from week 1 - 1 month
6-7L/day
feeding of calf from month 1 - month 2
5-6L/day
feeding of calf from month 2 - month 3
3-4L/day
feeding of calf from 3 months - 6months
> 1.5kg/day dry feed
What increases the size of the rumen
increase in VFA
how to improve microbiome etablishment
give solid feeds from week 2
what triggers papilla development
fibres from hay
oesophageal groove reflex
directs milk from moth to abomasum
temp of milk replacer
37-38o
conditions of milk replacer that causes the oesophageal reflex
intake
age
chemicals - copper sulphate
water requirement of calf at month 1
8-10L/day
water requirement of calf at month 2
10-15L/day
caesin digestion
prorenin becomes renin for caesin fermentation
how is milk fat digested
by lipase
how is lactose digested
lactase
(because - maltose, saccharose dont develop until 3-4weeks)