Energy

Question 1

What are energy systems

Answer 1

• Set of rules relating energy intake to performance or production

Question 2

How do we use energy systems

Answer 2

• Predict performance based on particular energy level fed
• Calculate energy required to achieve desired performance

Need:
* Energy value of feed/feedstuffs
* Energy requirements of anima

Question 3

Scandinavian feed unit system (Starch equivalent system)

Answer 3

All feed is compared on a standard basis to 1kg of barley grain

Question 4

How is k ( efficiency of ME utilization ) related to amount of fiber in diet?

Answer 4

• As the fiber content increases,
  k
  k typically decreases.
• This decrease occurs because fibrous materials require more energy for digestion and fermentation in the rumen, leading to lower efficiency in converting ME into useful energy for the animal’s metabolic processes

Question 5

ME concentration cannot be calculated until ration has been formulated- why?

Answer 5

• it is a variable factor
• ME concentration of diet depends on digestibility of diet

Question 6

As DMI increases , what hapens to rate of passage

Answer 6

• Increased rate of passage
• Reduced rumen retention time
• Decline in feed metabolisability
• Decline in ME efficiency (k-value)

Question 7

ME requirement for maintenance increases by 1.8% for each unit increase in level of feeding
above 1 . TRUE or FALSE

Answer 7

TRUE

• E.g. Level of feeding for cow = 3.67 (209/57)
• ME requirement is 2.67 x 1.8 = 4.81%