Lecture 14 - Nutritional Requirements

Question 1

Total Energy requirement is a sum of…

Answer 1

maintenance and production requirements

Question 2

Basal Metabolic Rate (BMR) is … and is influenced by…

Answer 2

energy required to maintain the body at basic level to support primary processes
bodyweight (BW), environmental temperature and activity level

Question 3

BMR can be measured by …

Answer 3

Direct and Indirect calorimetry

Question 4

Direct Calorimetry and fasting metabolism

Answer 4

Insulated aerated chamber
over periods of 24h it is generally safe to assume that the quantity of heat lost by animal equals to quantity produced
Since the “no activity” parameter is impossible to obtain with animals, instead of basal metabolism we say that this measure “fasting metabolism”

Question 5

Indirect Calorimetry

Answer 5

Heat is produced when nutrients are oxidized, and so energy is calculated on the basis of oxygen consumption and carbon dioxide production

Question 6

3 conditions for both direct and indirect

Answer 6

1 fasting
2 thermo neutral zone
3 no activity

Question 7

Metabolic Body Weight formula and how to use it for BMR

Answer 7

bodyweight (BW) raised to 0.75 due to rubner’s surface law
BMR (kcal/day) = 70 x BW^75
bc an average 70kcal of heat are produced per kg of metabolic bodyweight per day

Question 8

How to calculate Energy Requirements for Maintenance (ERm) and how is it expressed

Answer 8

BMR + energy used for food intake, heat outside of thermoneutral zone and physical activity
energy required per unit of metabolic body weight (BWkg0,75)