Week 5 Flashcards
what feeds should you test
hay (due to variability)
byproducts (distillers, brewers grains, etc)
when should i save my money on feed testing
common feedstuffs
pasture
forage mineral analysis to develop your own mineral
when should you sample hay
each load or cutting (make 1 composite for each)
at least 10% of bales
how to sample hay
go into side of bail to get multiple layers and thus a better representation; sample above the curve; first and fourth cutting are best
DM
Dry matter
CP
crude protein
TDN
total digestible nutrients
NDF
neutral detergent fiber
NFC
non-fiberous carbohydrates
EE
ether extract (ie lipids)
Ash
chemical fraction that contains minerals and soil contaminants; no energy content
TDN value of hay for cattle and horses
would not be the same
estimating TDN
ADF and crude protein
summative equations
add digestible energy containing fractions together to determine TDN (NDF, NFC, CP, EE)
digestible NDF is best determined using an
in vitro analysis (take rumen fluid and mix with feed, determine whats left after rumen microbes have digested)
NFC=
100-CP-NDF-EE-Ash
analysis to request for hay (typical)
DM, CP, NDF, NFC, Ash, TDN
digestible NDF
analysis to request for hay (others to consider)
Ca, P, K
Nitrates (want to know from a safety standpoint)
brown midribs and tifton 85
hard to determine with traditional analysis
wet chemistry
chemical fraction is measured directly (digestion, combustion, etc)
works for all samples
NIR or NIRS
near infrared reflectance spectroscopy
estimates ______ using ______
chemical fractions; statistical relationship
____ is key
database
works well for
some feeds but not others
