Lecture Final Flashcards
The series of chemical, biochemical, and physiological processes which transform food elements into body tissues and activities
nutrition
any chemical substance that can be used and is necessary for maintenance, production, and health of animals
nutrient
the combination of mechanical, chemical, and enzymatic processes occurring in the GI tract that prepares ingested material for absorption by reducing particle size and increasing water solubility
digestion
passage or movement of the end products of digestion (nutrients) through the wall of the GI tract to the general circulation (blood)
absorption
movement of nutrients from the absorptive sites to the various cells in the body via the bloodstream
distribution
sum of all physical and chemical processes by which living, organized substance is produced and maintained
metabolism
any constructive process by which simple substances are converted by living cells to more complex compounds
anabolism
any deconstructive process by which complex substances are converted by living cells to more simple compounds
catabolism
the removal from the body of unusable materials and waste products of metabolism
excretion
any material of natural or synthetic origin, fed to animals for the purpose of sustaining them (may or may not contain all nutrients required by the animal)
feedstuff
combination of feedstuffs used to supply vitamins and nourishment to the animal
diet
amount of diet consumed by an animal in a 24-hour period
ration
feed or feed mixture used with another diet to improve the nutritive balance of a diet and the performance of an animal (protein, vitamin, mineral)
supplement
feedstuff which supplies nutrients high in energy and contains less than 18% crude fiber
concentrate
a feedstuff containing more than 18% crude fiber
roughage
Analytical method
- complete ID
- obtain a representative sample
- grain: obtain while filling or emptying
- hay: drill core is best
sampling
Analytical Method
- most widely used
- includes DM, ash, Kjeldahl N, ether extract, CF, NFE
proximate analysis
Ash
overall mineral
Kjeldahl N
crude protein
ether extract
lipid
crude fiber
carbs (non-digestible)
NFE
carbs (digestible)
Where are vitamins included in proximate analysis?
fat soluble: ether extract
water soluble: NFE
Analytical method
- partitioning fiber (cellulose, hemicellulose, lignin)
- NDF, ADF, ADL
Van soest analysis
NDF
hemicellulose, cellulose, lignin
ADF
cellulose, lignin
ADL
lignin
Analytical method
- computerized (rapid) and low cost
- dry, grind, expose to infared light
- each major organic compound reflects light differently
- database is not yet large enough
NIRS (near infared reflectance spectroscopy)
Analytical method
- not routinely done
- usually biological assays
- costly and time consuming
vitamin analysis
Dry matter basis
no water
as-fed basis
includes the water normally present in the feedstuffs
air-dry basis
~90% DM
As-fed to DM
nutrient concentration increases
weight decreases
DM to as-fed
nutrient concentration decreases
weight increases
supplies information about palatability and performance, but does not answer why
feeding trail
Digestion and metabolism trial procedure
- run PA on feed
- feed known amount
- collect feces
- run PA on feces
- calculate apparent digestibility
Apparent digestibility formula
100 x ((Nut. intake - Nut. feces)/Nut. intake)
Methods of fecal collection
metabolism stalls
feces collection bags
marker fed
indicator method
collect urine and feces separately, animal must be able to lay down and stand freely
- cons: no females, must bring food to them, digestion changes, environment change
metabolism stalls
- estimate fecal output
- marker should be inert, contain no element under investigation, and not diffuse
marker fed
- chromic oxide, lignin, naturally occurring chromagen compounds
- apparent digestibility = 100-100x(% ind in feed/% ind in feces)x(% nut in feces/% nut in feed)
indicator method
Measure of energy
- principle limitation: does not account for important, sometimes substantial, energy losses: urine, gas, heat
- over-estimates energy content of roughages
- expressed by weight, not calories
total digestible nutrients (TDN)
TDN formula
100x((dig. CP + dig CF + dig NFE + (2.25xdig EE))/lb consumed)
Energy flow chart
GE -> DE -> NE (NEm+NEp)
- fecal energy = GE-DE
- urine, gas energy = DE-ME
- heat energy = ME-NE
Carbonaceous concentrates
cereal grains
grain milling by-products
other high energy feeds
- contain large quantities of carbs
- most are processed
- less than 20% CP and less than 18% fiber
- high energy, low fiber, low CP
cereal grains
cereal grains include
corn, sorghum grain (milo), oats, barley, rye, wheat and rice, millet and triticale
- widely used
- very low in Ca, Lys, and Trp
corn
- 95-98% feeding value of corn (monogastrics)
- 85-90% feeding value of corn (ruminants)
- must be processed for monogastrics
- higher than corn in CP but variable (8-12%)
- drought resistant value for ruminants
- tannins (toxic factor, affect CP digestion)
sorghum grain (milo)
- 85% feeding value of corn
- very palatable high fiber
- groats (hulled) are equal to corn
oats
- 88-90% feeding value of corn (ruminants)
- 80% feeding value of corn (monogastrics)
- limited use for swine and poultry
- most used in brewing industry
- high fiber
barley
what 4 grains are fed most
corn, milo, barley, oats