Dietary energy Flashcards
(33 cards)
the ability to do work; not a nutrient
Energy
in animal nutrition, unit of energy is expressed in terms of _____
Heat energy
basic measure of energy which is the amount of heat needed to raise the temperature of one gram of water by 1C
Calorie
energy content of a matter is determined using an instrument called _____
Bomb colorimeter
AMOUNT OF ENERGY CONSUMED BY AN ANIMAL IS SUBJECTED TO A NUMBER OF LOSSES:
Loss through:
Feces
Gaseous products of digestion
Urine
Heat Increment: Heat of fermentation, Heat of nutrient metabolism
first loss of energy during digestion
Loss through feces
second source of energy loss
Loss through gaseous products of digestion
third source of energy loss
Loss through urine
represents nutrients that have been digested and absorbed into the body but are excreted through the urine
energy loss through urine
energy from the undigested portion of the feed; also include small amount of energy from worn out cells from the intestine walls
energy loss through feces
the heat produced in the digestive tract as a result of microbial action, which is quite extensive in ruminant animals
Heat of fermentation
the heat produced by the work which the body must do to digest, absorb, and metabolize nutrient
Heat of nutrient metabolism
heat generated when a feed is completely oxidized/burnt
Gross energy
the amount of energy apparently absorbed from a feed
Digestible energy
can be determined relatively easily by a digestion trial
Digestible energy
determined by subtracting energy losses in urine, end products of metabolic processes, and end products of endogenous origin, and combustible gases from DE
Metabolism energy
determination must involve collection of feces, urine, and gaseous losses
Metabolization energy
slightly more accurate than DE in terms of estimating the available energy, but more expensive to determine
Metabolizable energy
determined by subtracting energy losses due to heat increment from ME
Net energy
most accurately predicts the available energy for the animal
Net energy
NE for basal metabolism, voluntary activity, thermoregulation
NE for maintenance
NE for growth/weight gain, draft/work, milk, wool/hair, reproduction
NE for production
widely being used in formulating diets for various ruminant species
Net energy
a figure which indicates the relative energy value of a feed to an animal
Total digestible nutrients (TDN)
