Protein And Energy Imbalances In Ruminants

Question 1

What factors affect productivity?

Answer 1

Genetics

Feeding - Diet

Environment

Management

Disease

Question 2

What is the most expensive part of cow management?

Answer 2

Feeding

Question 3

What rumen pH is ideal?

Answer 3

Neutral

Question 4

How can a neutral pH be maintained in the rumen?

How can this be facilitated?

Answer 4

Saliva acts as a buffer

Produced by chewing and ruminating.
Therefore need a comfortable environment and enough time.

Needs fibre in diet 2-4cm in length.

Question 5

Why does dietary fibre need to be 2-4 cm in length?

Answer 5

Below that, doesn’t stimulate rumination

Question 6

How long does a cow need to lie down for per day?

What could disturb this?

Answer 6

14 hours/day

Feeding, cleaning, milking - cows are moved

Question 7

What is meant by the term “time budget”

Answer 7

Amount of time cows spend doing things key things

E.g. eating, ruminating etc

Question 8

How can you assess cow comfort?

Answer 8

Observe cows undisturbed in straw yards or cubicles

60% should be lying down/ruminating

1 hour before feeding (when they are disturbed) 85% should be lying down

Question 9

What is the difference between nutrition and feeding?

Answer 9

Nutrition = what they are fed

Feeding = what they actually eat

Question 10

When may feeding not equal nutrition?

Answer 10

If the food isn’t palatable/ fresh

Question 11

How can trough space affect feeding?

How much trough space is needed per cow?

Answer 11

Each cow needs enough space, at least 60cm per cow

If not, cows will not get access to equal amounts of feed

Sometimes 1st lactation heifers are bullied by other cows and pushed to the back of the queue if limited feeding space

Question 12

Other than space per cow, how can the trough affect feeding?

Answer 12

Physical condition of the trough - sharp or rough edges

Cleanliness - is fresh food put on old food? NEEDS TO BE CLEARED

Question 13

How should water be presented to cows?

Answer 13

Plenty of CLEAN water

Enough space around the trough

high enough flow rate

Clean trough

Cool (in summer)

Correct TDS

Question 14

Why do water troughs need to be big?

Answer 14

Cows like to drink in groups

Question 15

What is DMI a measure of?

Answer 15

Dry matter Intake

How much the cows are actually eating

Question 16

How can you estimate the required dry matter intake for a milking dairy cow?

When can’t this estimate be used?

Answer 16

2.5% of body weight plus 1% of milk yield

DRY COWS

Question 17

What should you look for when assessing feed on farm?

Answer 17

Does it smell bad?

Is it mouldy?

Is it too soggy/dry?

Are the cows eating it?

Question 18

What is a key benefit of feeding a TMR?

Answer 18

Don’t have temporary acidosis caused by just feeding carbs

Feed forage and concentrates together

Question 19

What potential issues are associated with feeding TMR?

Answer 19

Sorting - cows only eat carbs because they taste better

Fibre length not long enough to stimulate rumen

Question 20

What issues can occur as a result of a hole in a silage pit?

Answer 20

Silage should be anaerobic

When air enters - Secondary fermentation of silage and heating

SPOILED - not palatable, lower nutritional value

Moulds can produce mycotoxins

Question 21

What feeding problems should you look for when on farm?

Answer 21

Insufficient feeding space
Rough edges of troughs, rails
Extremes of hot, cold, rain, light
Slippery floors

Self feeding from silage face
Very tight packed silage
Electric fences

Question 22

What issues are associated with self feeding from silage faces?

Answer 22

Food can collapse on heads

Hard to pull out silage

BAD

Question 23

What mistakes are commonly made regarding grazing?

Answer 23

Overestimating the value of grazed grass - quality is variable and difficult to assess. Long, dry summers =
POOR

Bloat from clover rich pastures

Magnesium deficiency

Question 24

How can grazing issues be reduced?

Answer 24

Buffer feeding

Silage/hay/TMR to supplement grass
Prevents over eating of hungry cows

Question 25

What is the ideal milk fat percentage?

Answer 25

4.2%

Question 26

What dietary factors affect milk fat percentage?

Answer 26

FIBRE LEVEL If concentrate:fibre is more than 60:40, milk fat will drop significantly Acetate:proprionate ratio Spring grass can be low in fibre

Question 27

What condition is associated with low bulk milk fat? What issues are associated with using this as the only method of diagnosis?

Answer 27

SARA Different groups within herd may have different milk fat- can hide low individual percentages

Question 28

What is the ideal milk protein percentage?

Answer 28

3.4%

Question 29

What causes milk protein percentage to drop? How long does this take to correct?

Answer 29

Drop in long term ENERGY intake (NOT LACK OF PROTEIN) Needs to be slowly built up

Question 30

How is dung scored

Answer 30

1-5 From loose and watery to stiff

Question 31

When might a score 1 stool be observed

Answer 31

(Loose and watery) If given high concentrates

Question 32

Describe the ideal cow shit.

Answer 32

Slow hand clap, Doesn’t stick to boots

Question 33

What should you do when BCSing cows?

Answer 33

Compare condition at different phases of the cow’s life cycle - dry cows - freshly calved - 2-4 weeks post calving - late lactation

Question 34

What is the transition period?

Answer 34

Critical 6 weeks either side of calving

Question 35

What can problems in the transition period result in?

Answer 35

Poor feed intake (DMI) post calving Metabolic disease - ketosis, fatty liver, fat cow, LDA Poor production Poor fertility (won’t cycle properly)

Question 36

What should the BCS of a dry cow be throughout the dry period?

Answer 36

BCS 3 or slightly lower NEEDS TO STAY THE SAME

Question 37

Why shouldn’t you make cows lose weight during the dry period?

Answer 37

Causes excess fat mobilisation making fatty liver etc more likely

Question 38

When could you reduce the weight of cows

Answer 38

Reduce food a bit in LATE LACTATION

Question 39

How can dry cows be divided into groups? How should they be fed differently?

Answer 39

Transition cows - 14 days before calving to calving - SAME DIET DIFFERENT QUANTITIES Far off cows - dry off until 14 days before calving

Question 40

What are metabolic profiles? What do they tell us?

Answer 40

Planned regular blood tests that look at the number of metabolites in normal healthy cows in the herd. How well cows are handling the diet OBJECTIVELY

Question 41

When should metabolic profiles be done?

Answer 41

On a regular, planned basis 4 times a year at crucial times After Spring turn out Mid/late Summer (variable pasture quality) After housing Late in winter housing period

Question 42

Other then the 4 planned times, when else might you do a metabolic profile?

Answer 42

After MAJOR DIET CHANGES Need to wait 10 days to allow cows to adjust

Question 43

What cows should be sampled for metabolic profiling ?

Answer 43

Normal, healthy cows NOT sick, unhealthy cows or ‘poor doers’ ``` Sample 6 from: Early lactation (10-20d post calving) Mid lactation (100-200d post calving) Dry cows (within 14d calving- transition) ```

Question 44

What common errors are made when performing metabolic profiles?

Answer 44

Sampling cows calved more than 20d Failure to include lactation 1 cows in each group Sampling immediately after diet change Including poor or problem cows