Diary cattle nutrition Flashcards
1
Q
___ % is small intestine
A
20%
2
Q
___% is cecum
A
3%
3
Q
___ % is large intestine
A
9%
4
Q
NDF
A
structural CHO: hemicellulose and cellulose (cell wall + lignin)
5
Q
ADF
A
cellulose
6
Q
nonstructural CHO include
A
cell contents: organic acids, sugars, starches, fructans, pectic S, B glucans
7
Q
_____ come together to create VFA in rumen
A
fiber and starch
8
Q
net energy feed values table
A
?
9
Q
lipid digestion in ruminants
A
lipid to glyceral to VFAs
or lipid to SFAS
or lipid to UFAs to SFAs (biohydrogenation
10
Q
SFAs and UFAs are
A
excreted into small intestine
11
Q
vitamine A (retinol)
A
absolute requirement
12
Q
Vitamin D (cholecalciferol)
A
synthesized by ultraviolet radiation of the skin, but is typically also supplemented to dairy cows
13
Q
Vitamin E (tocopherol)
A
absolute requirement
14
Q
Vitamin K (phylloquinone)
A
synthesized by ruminal bacteria to meet requirments
15
Q
ruminal bacteria synthesize most ___ vitamins
A
water-soluble (so true deficiencies of these viamins are rare)
16
Q
there are some benefits to supplementing ___
A
niacin and biotin
17
Q
water-soluble vitamins include
A
thiamine nicotinic acid pantothenic acid choline vitamine b12 riboflavin pyridoxine biotin folic acid vitamin C
18
Q
water intake increases with
A
milk production and temperature
19
Q
to meet nutrient demands of high-producing dairy cow:
A
increase DMI
increase nutrient density of diet
20
Q
dairy cow phase 1 (early lactation)
A
0-10 weeks
peak milk production occurs wihtin 3-6 wks
21
Q
phase II (mid lactation)
A
10-24 weeks
milk yield begins to decrease, peak DMI occurs within 11-1 wks
22
Q
phase III late lactation
A
> 24 weeks
milk yield continues to decrease; cows regain body tissue reserves
23
Q
phase IV dry period
A
5-8 wks dry period, late pregnancy (rapid fetal growth)
24
Q
phase V transition period
A
2-3 wks
dry period; late pregnancy; prepare for lactation
25
dairy cow production stages chart?
x
26
physiologic priority during phase 1
lactation
reproduction
growth
maintenance
27
physiologic priority during phase 2
reproduction
lactation
growth
maintenance
28
physiologic priority during phase 3
reproduction
growth
maintenance
lactation
29
goal of feeding dairy cows
provide high energy diets to allow cows to achieve their genetic potential to produce milk
30
dairy cow dilemma
feeding high-grain diets= more milk, but too much dietary starch may damage rumen papillae (parakeratosis) and depress milk fat due to inadequate intake of dieatry fiber
31
challenge of dairy cow feeding
feed diets with sufficient energy to support maximal milk production while maintaining adequate dietary fiber levels to avoid rumen damage and milk fat depression
32
impact of type of diet on rumination time, saliva production and rumen ph
more salivation and rumination causes more alkalotic rumen PH; small difference in PH will have huge difference on microbes
33
starch loving microbes
increase with increase in grain (get more propionic acid)
34
fiber loving microbes
increase with increased roughage diets; (more acetate less proprionate)
35
acetate is needed for
milk production
36
how does inadequate dietary fiber level depress milk fat synthesis?
```
increase grain provides for starch loving microbes
increase lactic acid production (decrease ph)
increase starch loving microbes more
decrease fiber loving microbes
decrease rumination time
decrease production of saliva
decrease dietary fiber digestion
decrease acetic acid production
decreae milk fat synthesis
```
37
how do we maintain adequate fiber levels in lactating dairy cow diets
1. formulate diet to contain a minimum forage: concentrate ratio of 40-60
2. formulate diet to contain minimum of 17% crude fiber or 21% acid detergent fiber (adf more accurate measure of fiber content of feed)
3. feed minimum of 1-1.5% body weight as a forage
38
rules of thumb that do not always work
x
39
ROT: better to consider ____ level of the diet, not just total fiber level
effective fiber level
40
ROT: effective fiber is defined as
the properties of a feed that cause a cow to chew
41
ROT: the higher the effective fiber in a feed,
the more time a cow will spend chewing and or ruminating
42
effective fiber of a feed is dependent on
```
particle size (long stem vs pellets)
amount of fiber (FC, ADF, or NDF)
type of fiber (proportion of lignin)
```
43
roughage value index (RVI) is determined by
measuring the amount of time a cow spends chewing
44
RVI is expressed as
minutes per chewing per unit of feed DM
45
roughage value index in order from least to greatest
barley grian,alfalfa pellets, corn silage, long stem alfalfa hay, med. quality hay
46
what is a method to measure effective fiber
penn state particle size seperator
47
impact of particle size of ration on performance of lactating dairy cows
fine particle size caused cows to ruminate less, produce less saliva and favored microbes that produce starch
48
short term benefits of including adequate levels of effective fiber in the lactating cow diet
chew more and provid emore saliva based bufferes to the rumen which will increase rumen ph and provide an environment more faborable for fiber-loving microbes; increase acetic acid production which is the precursor of milk fat synthesis
49
long term benefits
help maintain integrity of the rumen epithelial tissue thus preventing rumen parakeratosis (rumen burnout)
50
other nutritional factors that will affect milk consumption
type of grain
grain processing
dietary buffers
51
types of grain
cows fed grains which have a faster rate of rumen starch fermentation are more likely to have depressed milk fat
wheat>barley>corn and milo
52
grain processing
the more a grain is proessed the faster the rate of rumen starch fermentation
(steam flaking> cracked or dry rolled > whole)
53
dietary buffers
adding buffers to diet will increase rumen ph and help to minimize milk fat depression
54
dietary fats
adding fat to the diet may decrease milk protein
55
rate of starch fermenation differs by grain source
wheat most rapid
barley intermediate
milo less rapid
corn less rapid
56
the more you process grain,
the more rapid fermentation more likely you will have acidosis
57
sodium bicarbonate can be added to the diet at ____ of diet dry matter
1%
58
situations when dietary buffers are beneficial
```
high cornsilage based diets
high grain diets
low effective fiber diets
heat stress
when cows are off feed (early lactation)
```
59
energy density of the diet can be increased by
replacing a portion of the grain in the diet with fat
60
fat added diets allow more energy intake while avoiding
excess starch or low fiber intakes
61
including more than 8% fat in th etotal diet will cause
DMI to decrease
fiber digestion to decrease
incidence of digestive upsets to increase
62
most grains and forages contain ____ fat
3%
63
therefore, fat can be added to diets at ___ without adverselyaffecting DMI or digeestibility
5%
64
high producing cows within the first ______ of lactation benefit most from fat-added diets
2-5 months
65
cows fed fat-added diets typically produce ___ more milk per day
4-6 lbs
66
cows fed fat-added diets lose less weight during
early lactation
67
____ cows eat less and produce less
heat stressed (>80F)
68
feeding fat-added diets to heat -stressed cows is beneficial because
heat increment is decreaed
69
feeding fat-added diets may _____ the incidence of ketosis and _____ reproductive performance
reduce
| enhance
70
sources of fat for lactating dairy cows
plant oil seeds
unprocessed fat sources
processed fat sources
71
plant seed sources
cottonseed
soybean
canola
72
unprocessed fat sources
tallow
| hydrolyzed animal-vegetable oil blends
73
processed fat sources
Ca salts of fatty acids
| prilled fat
74
rumen inert fats (bypass fats)
do not disrupt rumen fermentation of fiber like unprotected fats (tallow)
75
rumen inert fats help maintain
BCS during negative energy balance when dry matter intake is limiting
76
increasing the energy density of the ration helps minimize
rebreeding problems, maximize milk production and maintain body condition
77
traditional feeding system
forage and concentrate based feeds are fed separately
78
steps to traditional feeding system
determine nutrient requirements
estimate forage DMI
estimate forage nutritional quality
challenging to formulate concentrate mix to supply nutrients beyond what the forage provides
79
total mixed ration feeding system
forages and concentrates mixed fed together
80
steps to tmr feeding system
determine nutrient requirements
estimate forage DMI (easy cause not grazing)
estimate forage nutritional quality (easier for harvested forages)
formulate TMR
81
advantages of using a TMR feeding system
cows not permited to eat fav forage
cows forced to eat correct balance of forage and concentrate
numerous meals throughout day; helps maintain ph
easier to feed cows in variouus groups
reduce incidence of social dominance
82
advantages of using traditional feeding system
harvesting and chopping forages for TMR system is expensive
costs of grazing forages as part of traditional system is cheaper
cost of feeding equipement for traditional system is less expensive
83
BCS 1-1.5 dairy cow
severe under condition
84
BCS 2-2.5
thin
85
BCS 3-3.5
moderate
86
BCS 4-4.5
fat
87
BCS 5
severe over condition
88
study BCS images
x
89
desired and reasonable BCS for dairy cows at calving
3.5; 3-4
90
cows at peak milk
2; 1.5-2
91
mid lactation
2.5; 2-2.5
92
dry off
3.5; 3-3.5
93
heifers at 6 months
2.5; 2-3
94
heifers at breeding
2.5; 2-3
95
heifers at calving
3.5; 3-4
96
Phase 1 nutritional goals to achieve during early lactation
maximize intake (for every pound of DMI, milk production will increase by 2.5 lb)
minimize body tissue loss
97
one lb of body tissue mobilized during early lactation will supply
energy for 7 lb of milk
| protein for 3.5 lb of milk
98
feeding recommendations for phase 1
high quality forage
palatable feed with high energy density
adequae effective fiber levels (min 20% ADF)
consider adding fat
use all natural protein supplements (no urea, NPN)
consider high quality bypass protien sources (UIP)
99
the _____ of protein in UIP fed to riminants is important
quality
100
what are the goals of phase II
maintain high milk production
| beginto regain body condition lost during early lactation
101
phase II feeding recommendations
use palatable feeds with high energy density
use high quality forages
ensure adequate fiber levels
use all naterual protein supplements
102
phase III goals
restore BCS
limit overconditioning
target BCS at dry off: 3.25 to 3.5
103
phase III feeding recommendations
use lower costs feeds when possible and meet needs
| consider use of NPN to meet a portion of protein needs
104
why feed dairy cow to replace body fat during late lactation>
????
105
phase IV goals
optimize fetal growth
prepare cow for next lactaion
minimize length of dry period (60 days)
achieve BCS of 3.5 at calving
106
phase IV recommendations
separate dry cows from lactating
avoid high grain diets to prevent abomasal displacement
avoid feeding excessive Ca levels to prevent milk fever
107
phase v goals
acclimate the rumen microbes to the diet that will be fed during early lactation
allows cows to be rapidly switched to a high grain diet with minimal digestive upsets
108
phase V feeding recommendations
feed .5 to 1.0 % of BW as grain to prevent acidosis
continue to limit intake of Ca to prevent milk fever
feed high levels of vitamein a and e to prevent mastitis
109
high producing cows are forced to make major ____ at calving
metabolic adjustments
110
tremendous nutrient demand shifts occur at
calving as cows redirect nutrient utilization to support high levels of milk production
111
cows have remarkable ability to _____ in an attempt to maintain homeostasis
mobilize body tissues (lipid, Ca, protein)
112
ability to consume feed lags behind the demand for nutirients during
first 8-10 weeks of lactation
113
during this period, cows are susceptible to
nutritional disorders
114
nutritional disorders in early lactating dairy cows include
```
milk fever
ketosis
retianed placentas or metritis
fat cow syndrome
displaced abomasum
mastitis
```
115
incidence of clinical milk fever
8-9%
116
more prevalent in
high producing cows, and in cows with previous milk fever history
117
80% of cases occur within ____ of calving
48 hours
118
rarely occurs in cows during
1st lactation
119
what are the symptoms of milk fever
hypocalcemia (
120
typical Ca levels in nonlactating cows is
9.4
121
typical Ca levels in fresh cows is
7.7
122
milk fever cows are more susceptible to
mastitis, ketosis, dystocia, displaced abomasum, uterine prolapse
123
an 1100 lb dairy cow requires ____ Ca per day
30-40g during dry period
124
feeding ____ during dry period increases incidence of milk fever
more than 100 g (mechanisms to absorb Ca from GIT an dmobilize Ca reserves from bone are down regulated)
125
preventing milk fever in dairy cows; traditional method
feed low Ca (
126
preventing milk fever newer method
feed negative dietary cation-anion balance (DCAB) diets during dry period
127
DCAB
sum of positively charged ions (cations) and negatively charged ions (anions)
128
a ____ DCAB before calving will activate mechanisms to absorb more Ca from gut and moblize more a from bone
negative
129
recommended DCAB is
-10 to -15 meq/100 g diet DM
130
to accomplish this,
avoid high K level forages
add sulfate salts until S is maximized at 0.4 to 0.5% in diet
add chloride salts until DCAB is lowered to -10 to -15
131
challenges to feeding negative DCAB diets
anion salts are more expensive
| high levels of anion salts are unpalatable (decrease DMI)
132
incidence of ketosis cases
2-15 %
133
aboute ____ of cows exhibit borderline ketosis
50%
134
most cases occur within ___ of calving
60 days
135
symptoms of ketosis
elevated ketone bodies
normal levels of ketone bodies
depressed blood glucose levels
distinctive acetone-like odor of the breath and fresh milk
appetite decrease; milk production decreases
cows develop ketosis gradually
cows seldom die from it
136
prevention of ketosis
```
avoid excess BCS at calving
good transitiondiet in Phase V
maximize DMI during Phase I
feed oral glucose precuroses
feed niacin for 2 weeks precalving and first 2-3 months of lactaton
```
