Lecture quiz 5/10/23 (wednesday)

Question 1

What do we have to balance first before the other nutrients?

Answer 1

ENERGY

Question 2

what would happen if we do not have enough energy?

Answer 2

lose weight

Question 3

what accounts for the different loses?

Answer 3

gross energy

Question 4

How is gross energy measured?

Answer 4

bomb calorimetry of feed and feces

Question 5

how do we calculate the digestible energy?

Answer 5

DE= GE-FE

Question 6

what is digestible energy?

Answer 6

represents the amount of energy that is absorbed by the animal
- it is not all available fo the animal to use

Question 7

what is metabolizable energy?

Answer 7

ME- DE-UE (MtE for ruminants)

UE - urinary energy
- collect urine by catheter or cup
- bomb calorimetry

Methane energy
- measure methane production in respiration chamber
- apply value for heat of combustion (-212.5 kcal/mol)

ME= GE - FE - UE & Methane E (ruminants)

Question 8

what does ME representt?

Answer 8

represents the portion of the ingested gross energy left after accounting for losses in feces, urine and methane gas
- not all available for the animal to use

Question 9

what is Net energy?

Answer 9

NE= ME- Heat increment

Question 10

how is heat increment measured?

Answer 10

use equations (estimated values)
bottom up approach to calculate for NE
NE = HE (from maintenance) +NEp ( retained energy in tissues, milk, concepts, etc/)

Question 11

what is HE (from maintenance)

Answer 11

by measuring HE during fasting or minimal activity
- heat increment (HI) = 0 by definition under these conditions