Ruminant nutrition general

Question 1

Metabolizable energy equation

Answer 1

Metabolizable energy = gross energy - energy lost in faeces/urine/methane

Question 2

Main sources of energy in the feed

Answer 2

Carbohydrates
Fats/lipids
Pre-formed VFAs

Question 3

Fermentable metabolic energy equation

Answer 3

FME = ME - energy from fats and VFAs

Question 4

Crude protein estimate

Answer 4

Multiply the amount of nitrogen in feed by 6.25

Question 5

Rumen degradable protein

Answer 5

RDP - Quickly degradable protein (QDP) and slowly degradable protein (SDP)
A low yielding cow will have a higher percentage of slowly digestible protein than a high yielding cow.

Question 6

Undegraded protein

Answer 6

UDP - Digestible undegraded protein (DUP) and non-digestible nitrogen (ADIN)
A high yielding cow will have a higher percentage of DUP than a low yielding cow.

Question 7

Metabolizable protein equation

Answer 7

MP = (MCP * 0.64) + DUP
Where MCP = microbial protein

Question 8

Acid detergent fibre (ADF)

Answer 8

Comprised of cellulose and lignin - min 19% in ration

Question 9

Neutral detergent fibre (NDF)

Answer 9

All fibre (hemicellulose, cellulose, lignin), recommended 30% in diet

Question 10

Which group is the most likely to be energy deficient

Answer 10

Dairy cows: Early lactation (10-20 days after birth) - high yielders
Suckler cows: late pregnancy (last 2 weeks)
Sheep: 2-3 weeks before lambing due to start

Question 11

Energy metabolites measured

Answer 11

BHB - high when energy problem
NEFA - measures fat mobilisation so high when energy problem
Glucose - low can reflect weight change

Question 12

Protein parameters measured

Answer 12

ureaN - reflects the balance between RDP and FME
Albumin - low when longer term poor protein supply or liver problems
Globulin - reflects chronic inflammation