Nutrition II Flashcards
1
Q
What is fermentation
A
A method of feed digestion
Oxidative
2
Q
how many type of ruminants are there
A
over 180
3
Q
capacity of the rumen
A
80-100 L
4
Q
What is the rumen lined with
A
Filiform and Foliate epithelium for increased SA for VFA absorption
5
Q
Function of Cranial Pillar
A
Holds digesta away from oesophagus, allows eruction of gases
6
Q
Appearance of reticulum
A
honeycomb structure
7
Q
function of reticulum
A
controls flow rate of digesta
8
Q
omasum
A
filters digesta in folds called laminae and flushed back into rumen for rumination
9
Q
what protects abomasum
A
mucus from pepsin and HCLM
10
Q
Where does the first stage of protein digestion occur ?
A
abomasum
11
Q
3 types of rumen microbiota
A
bacteria, eukaryota, archaea
12
Q
what % of rumen bacteria bind to feed particles
A
75%
13
Q
function of rumen bacteria
A
Digest starch, Sugars, Lipids, Proteins
14
Q
2 types of rumen bacteria
A
Fibre digestion ( Cellulolytic)
Starch & Sugar Digesters( Amalytic)
15
Q
What % of the rumen do Amylolytic bacteria take up
A
25%
16
Q
Fibre digesters work greatest on forage diets but don’t suit high fat diets above what
%
A
no greater than 5%
17
Q
Fibre digesters primarily work on what?
A
Cellulose, Hemicellulose, Pectin
18
Q
What is an example of a lactate using bacteria in the rumen
A
Megasphaera elsdenii
19
Q
What % of the rumen do Protozoa take up
A
50%
20
Q
What are the advantages of Rumen Protozoa
A
Single cell Eukaryote
Long residency time in the rumen
Attach to feed particles
21
Q
How long does it take rumen protozoa to grow
A
15+ hrs
22
Q
location of rumen protozoa
A
fibre mat of the rumen
23
Q
How can rumen protozoa benefit the rumen?
A
They can eat large amounts of starch at one time and store it in their bodies which in turn
slows down the production of acids that lower the PH of the rumen.
24
Q
optimum pH for:
cellulose digestion
formation of VFA
synthesis of protein
lactate production
A
cellulose digestion 6-6.8
formation of VFA 6.2-6.6
synthesis of protein 6.3-7.4
lactate production 5.9-6.2
25
Nitrogen is essential for what
Producing microbial protein in ruminants
26
How can we reduce N losses from dairy cows
Either by reducing dietary N or increasing N use by rumen microorganisms
27
What is a solution excess N being produced
Forages with lower concentrations of N and less soluble protein
28
An example of a structural carbohydrate
lignin
29
How is degradability of forages measured
In vitro gas production technique or via in sacco nylon bag technique
30
Wheat and barley straw have a soluble fraction of what
15%
31
PRG & white clover have a soluble DM of
30-40%
32
What sort of a process is fermentation
Oxidative process
33
fermentation
It is a metabolic process in which an animal converts a carbohydrate into an acid or an
alcohol.
34
What is a major constituent of plant cell walls
Cellulose. Made up of B(1-4) Linkages
35
What is cellulose starch and sugars broken down into
hexose
36
What are 3 main factors affecting fibre fermentation
Rumen PH
Diet Digestibility
Rumen Passage rate.
37
What causes the Ph of the rumen to decline
When VFA absorption is faster than VFA production
38
What is meant by rumen passage rate
Flow of digesta out of the rumen
39
What influences Passage rate
Complex CHO - Slow passage rate due to high structural content
Simple CHO - Fast passage rate as the small particles are rapidly broken down in the
rumen.
40
degradability
Degrading of feedstuff in the rumen
41
digestibility
How much of the nutrients consumed are absorbed and digested in the G.I (Reticulum &
Abomasum)
42
What are other methods of measuring digestibility
NDF, ADF and DM
43
What is the key functions of metabolizable protein
Growth, Lactation, Pregnancy
44
Two types of Rumen Protein
Rumen Digestible protein
Rumen Degradable Protein
45
What is the primary source of protein supplied to the S.I by
Microbial protein synthesis accounting for 50-80% of total absorbable protein
46
What is the purpose of energy systems
Bring together information on energy requirements of animals as well as providing info on the energy supplied by diets.
47
What energy system is adopted in ireland
French system
48
What are the two main losses from DE
urine & methane
49
Losses from DE can be put down to:
Inefficient feed digestion
50
How is Gross energy measured
bomb calorimetry
51
What is the typical GE content of most feeds
18-20 Mj of GE/kg DM
52
What is the formula for digestibility
Digestibility = Feed intake - faeces output / Feed intake
53
Calculate the following
Cow eats 25KgDM and produces 7.5 kg DM. What is digestibility
0.7
54
What losses does Metabolizable energy account for?
Losses through urine and gases lost from the rumen
55
Methane typically makes up what % of GE
8-9%
56
Methane typically takes up what % of DE
10-11%
57
Urine typically takes up what % of GE
3-5%
58
How is NE calculated
ME - HI
59
How is HI calculated
Indirect calorimetry
60
What is indirect calorimetry
A method estimating heat production through oxygen consumed, carbon dioxide produced and N in the urine.
61
Two types of respiration chambers
Open and closed circuits
62
What is the maintenance requirement for a 600 kg cow
M= 1.4(0.6*BW)/100
M=1.4(0.6*600)/100
M=5.04 UFL
63
WHat is the requirement for milk of a cow producing 25kg milk and 3.8% fat
Requirement for milk = 0.44*(0.4+0.15*FC)
= 0.44(0.4+0.15*3.8) = 0.43
Per 25kg = 25*0.43 = 10.75 UFL
64
What is the formula for 1 kg BW loss
3.5 x BW loss
65
What is the formula for BW gain
4.5 x BW gain
66
A loose housed animal will have an increased requirement of what
10%
67
A Pasture based animal will have an increased requirement of what
20%
68
Outline the energy requirements for pregnant cows in order of months and UFL
0.9 7 month
1.6 8 months
2.6 9 months
69
Feed intake is a function of what?
Meal size and meal frequency
70
What is one of the best indicator of ill health in ruminants
Decrease in DMI
71
When an animal reaches their rumen capacity it is called
Distension
72
When Distention occurs the brain detects high levels of what?
High levels of digestion end products in the liver and the animal will stop intake until the concentration decreases
73
What is the Thermoneutral zone of a dairy cow
Minus 15 degrees to plus 25 Degrees
74
What are 3 characteristics influencing Ruminant feed intake
Food Factors, Animal factors, Environmental factors
75
Every 100 kg increase in BW will result in
3KG increase in DMI
76
Overly fat animals will produce what hormone
Leptin which reduces intake
77
The 5 Key nutrients in ruminants in order
Air Water Energy Protein Vitamins minerals
78
5 factors affecting Energy requirements of ruminants
Maintenance Growth Health Lactation Reproduction gestation
79
What is the most important factor influencing performance
Dry matter intake DMI
80
What directly controls the amount of energy consumed and available for metabolism
DMI
81
Sub optimal DMI can result in
Metabolic disease and reduced performance
82
What % of BW does DMI typically take up in a diet
2-4%
83
Two important Hormones in feed regulation are what?
Neuroendocrine system and hormonal secretion
84
What stimulates feeding behaviour
Orexigenic signals
85
What is inhibits feeding behaviours
Anorexigenic signals
86
What are examples of Inhibitory signals
Rumen distention
Rumen Osmolality
Gut peptides
Pancreatic hormones
Adipokines
87
The main characteristics affecting intake in ruminants
Rumination and fermentation of fibrous feeds
Retention time
Rumen capacity
88
As digestibility of a forage increases so too does intake, due to
faster passage rate
89
4 key minerals to ensure a ruminant is not deficient in
S P Na Co
90
What are the main environmental factors affecting feed intake
Heat , Rain , Grazing factors , Temp , Day length , Parasite infestation, ill health
91
What is the ideal bite size for a dairy cow
0.6 g DM
92
What is the ideal bite rate for a dairy cow
60/min
93
What is the target time spent grazing per day by a dairy cow
8-10hrs
94
What will be a result of excessively hot weather
reduced intake
95
What will be a result of cold weather
increased intake
96
What are the main animal factors that can affect intake in ruminants
over fat animals
Very thin animals
Pregnant animals
Physiological status
97
What is the correct fill units for the following
Dairy cattle
Beef cattle
Sheep
Dairy cattle - LFU
Beef Cattle - CFU
Sheep - SFU
98
Maintenance takes up what % of energy that goes into a cow
60-80%
99
What effect will wet grass have on intake
Lower intake as water is filling up the rumen
100
Higher intake is associated with what
Short fibers
101
What is PDIMN
Microbial protein that could be synthesised when Nitrogen is limiting
102
What is PDIME
Microbial protein that could be synthesised when fermentable energy is limiting
103
Where does the main energy supply for Ruminants come from
Carbohydrates and Fats
104
What is the max inclusion rate for fats in a ruminant's diet
No more than 5%
105
WHat is the results if a diet has more than a 5% fat inclusion rate
Depression in intake
106
Two types of structural carbohydrates
Cellulose and hemicellulose
107
What are the end products of digestion
VFA
108
What are examples of VFA
Acetic, propionic, Butyric
109
Where are VFA absorbed
Rumen wall
110
What is meant by physically effective fibre
Ruminants require fibre in a coarse physical form
111
WHat content should NDF be of dietary dry matter
30% with at least 21% forage
112
What is a problem with the ME system
ME values are not necessarily related to an animal's maintenance or production
ME overestimates the available energy of forages relative to concentrates
113
The dietary CP requirements of cattle are
Minimum >7%
Young /Growing 13-15%
Finishing cattle 11-12%
Lactating dairy cows 14-17%
114
What is non protein nitrogen
Refers to components such as urea, biuret, and ammonia which are not proteins but can be converted into proteins by microbes in the ruminant stomach
115
Name 4 common types of forages used in ruminant diets
Grass
Legumes
Herbs
Brassicas
116
A type of grass very toxic to horses
vetch
117
What is true about legumes
They are rarely grazed on their own by ruminants bar sheep
118
Two examples of herbs
Chicory and plantain
119
What influences nutrient availability
Degradability
120
Grass silage has what % CP content
~12%
121
An example of a feed deficient in calcium
cereals
122
What is the most common cereal used in diets
barley
123
What is the max recommended inclusion rate of starch in a diet
max 50%
124
What is the CP content of Barley
10-12%
125
What is the OMD content of Barley
81-88%
126
What is the starch content of Wheat
65-70%
127
WHat is the max recommended inclusion rate of wheat
Max 40%
128
Wheat contains what
gluten
129
What is the CP content of wheat
10-16%
130
What is the max inclusion rate of wheat in sheep diets
max 50%
131
What are examples of high fibre energy supplements
Molassed beet pulp
Unmolassed beet pulp
Soya hulls
Molasses
132
Molassed beet pulp is rich in what
digestible cellulose
133
Molassed beet pulp has sugar content of what
20%
134
Examples of Cereal by products
Pollard/wheat bran
Maize gluten feed
Maize distillers
135
Examples of oil seed by products
Palm kernel meal
136
What is the fibre content of palm kernel meal
80-85%
137
What is the crude protein content of palm kernel meal
20-25%
138
Give two examples of protein supplements
Rapeseed meal
Soyabean meal
139
The fraction of fibre that stimulates chewing activity is called what ?
Physically effective NDF
140
What effect does physically effective NDF have on the animal
Enhances saliva flow
Increases milk fat levels
Maintains rumen PH
141
What is net energy primarily used for in ruminants
Production and maintenance
142
WHat are two main maintenance values
UFL and UFV
143
What does UFL relate to
Maintenance and production in dairy cows and sheep
144
WHat does UFV relate to
Maintenance and weight gain in fattening animals
145
Barley is best fed in what form
Rolled and dried
146
WHat supplement is essential to balance peNDF in the diet
Wheat
147
What is pearson's square
A tool used to calculate energy and protein supply
148
Why is methane produced
To use up H+ in the rumen of animals
149
What is a useful role of methane in ruminants
Helps maintain a microbial population
150
What % of methane come from enteric fermentation
57%
151
How many more times potent is methane than carbon
28 times more potent
152
Methane is best described as
A short lived gas
153
Co2 has a GWP of
1
154
An example of a gas short lived in the atmosphere and released from the use of
Fertilisers
nitrous oxide
155
Nitrous oxide is said to have a GW potential of
298
156
What % of irish water has unsatisfactory or poor quality due to free draining soils
43%
157
How long does methane live in the atmosphere
12yrs
158
Examples of nutrient dense products
Milk and meat
159
Since 1990 and 2017 there has only been a what % increase in methane emissions
1.7%
160
What is glycolysis
The breakdown of feedstuff into glucose
161
What is butyrate formed from
acetate
162
Where more acetate is produced so to is what
methane
163
What is the MJ/kg of energy provided by methane
55
164
What % of total microbes does archaebacteria make up
0.5 - 3.0%
165
What will help reduce CH4
By providing an alternative sink for H2
166
What is the capacity of the rumen of a cow
100 - 120 Litres
167
What is the PH of the rumen
5.5-6.5
168
Mastication accounts for what % of gas released from cows
90-95%
169
A proven method of reducing methane emissions
Oil inclusion in the diet
170
How is microbial protein formed
Ammonia + Energy
171
Main function of the rumen
Carbohydrate digestion
172
What most accurately describes methane production
Methane production is a function of the animal, the diet and the microbial population in the rumen
173
Where is most methane excreted by hind gut fermenters
Excreted through the breath from the lungs
174
What is one management strategy that can help reduce methane
Selection of animals with less of a genetic capacity to produce methane
175
Where are protozoa found
The fibre mat of the rumen
176
The removal of protozoa is responsible for
Significant proportion of methane production
177
Two minerals that have the potential to reduce methane emissions
fats and oils
178
The use of linseed oil has found what
A methane per day production decrease of 17%
Methane reduction per kg milk solids of 20%
179
What is ether extract
Total crude oil content of a forage
180
To reduce methane we can
Breed , Feed and supplement
181
WHat VFAs are involved in the production of methane
Acetate, Butyrate, Propionate.
182
What VFA is least energy dense
acetate
183
What VFA is most energy dense
butyrate
184
WHy is methane produced in the rumen
The rumen is a large energy making mechanism for certain groups of microbes which live in the rumen. Methane is formed as aby product of VFA fermentation by
185
What is the formation of methane known as
Methanogenesis
186
What % of methane is released as a result of belching
90%
187
What % of methane is released anally
5-10%
188
Methane accounts for what % of energy intake in animals
10-12%
189
A high concentrate diet will lower emissions in comparison to
a grass based diet
190
What are the advantages of including fat in a diet of a cow
Increases energy & reduces methane production
191
WHat is the max inclusion rate of fat in a diet
max 6%
192
What are the consequences of including fat above 6%
Inhibits CHO digestion
193
For every 1% of fat given to a cow, what % decrease in methane yield is observed
5-6%
194
Plant oils all have
High concentrations of polyunsaturated fats
195
Why is fat not included at high rates in diets
It has the ability to inhibit CHO digestion
196
Linseed oil has shown what % reduction in methane
17% daily
197
What is defaunation
The inhibition or removal of methanogens & protozoa using plant oils.
198
Seaweed has the ability to increase ADG by
22%
199
Seaweed can reduce enteric fermentation by what %
50%
200
What % of irish rivers have unsatisfactory nitrate concentrations
43%
201
What % of ireland's ammonia emissions does agriculture account for
99%
202
Agriculture accounts for what % of total emissions
37.5%
203
Enteric fermentation accounts for what %
56%
204
What are some of the requirements for derogation 2022
Low emission spreading after 15th April
Clover inclusion in reseeds
Crude protein limit at 16% from 1st april to 15th september
Commonage fert limit 50 kg N ha
Grass measuring and nutrient management plan
205
Protein is available in two forms. What are they
Rumen degradable protein
Rumen undegradable protein
206
RDP is degraded to what
ammonia
207
What creates microbial protein
Energy + Ammonia
208
True protein can be regarded as?
Microbial protein
209
Give the three functional groups
Grass
Legumes
Herbs
210
What is Multispecies forages
Forages that contain 2 or more plant species from at least two functional groups
211
WHat are some of the most common types of legumes
White clover
Red clover
Vetch
212
What are some of the benefits of Multispecies swards
High Nutritive value
Increased animal performance
Increased summer growth rates
Reduced chemical N use
Increased biodiversity
