energy Flashcards
what is meant by animal tissues are dynamic
constantly broken down and replaced
what do catabolic reactions do
generate energy
what do anabolic reactions do
require energy (ATP) to build something
examples of anabolic reactions
muscle contraction
active ion transport
gene expression
hormone secretion
cell division
adipose reserves
growth
lactation/egg production
what is energy balance
total energy provision = total energy needs
what is a positive energy balance
e provision greater than e needs.
stores energy so anabolism
what is a negative energy balance
e provision less than e needs
mobilise body e reserves so catabolism
process of calculating gross energy in a BOMB calorimeter
sample dried
known quantity of DM combusted in sealed chamber
energy released by oxidation of covalent bonds in warm surrounding water
what is the 4 types of energy
gross
digestible
metabolisable
net
what is the percentage of faecal loss
10-70
what is metabolisable energy
the energy assimilated by the animal and available to fuel metabolism
what are the factors affecting ME
digestibility eg fibre content, food prep treatments
species
diet quality - higher protein intake of carnivores increases urinary excretion of energy rich nitrogenous compounds.
nitrogen balance
feeding levels
heat increment of feeding
prehension and mastication
gut contractions
production and release of digestive enzymes and hormones
catabolism of nutrients within the guts and tissues
absorption of nutrients across the gut wall
specific dynamic action of feeding
Net energy
the amount of energy assimilated by the animal & available to fuel metabolic processes other than
those associated with the acquisition of nutrients
what do energy needs vary with
age
species
body size
production level
work
Ta
disease
