NUT 115-Midterm 2 Test With
Complete Solution
The use of laboratory techniques to determine the concentration of
nutrients(and energy) in a feedstuff or diet - ANSWER Chemical evaluation
The use of animals, in some way, to measureutilization of nutrients from a
given feedstuffvor diet - ANSWER Biological evaluation
What is the first step of chemical evaluation? - ANSWER getting a
representative sample
What are the 3 selections of analytical methods in chemical evaluation? -
ANSWER 1-Proximate Analysis
2-Van Soest Detergent Fiber Analysis
3-Near-Infrared Spectroscopy (NIRS)
How many categories for particle compounds are there in proximate
analysis?
-list them - ANSWER 1-Water
2-Crude Protein
3-Ether Extract (crude fat)
4-Crude Fiber
5-Ash
6-Nitrogen Free Extract (NFE)
,Proximate analysis pitter - ANSWER
How long are samples heated at what temperature in proximate
Analysis-Moisture (water)? - ANSWER 105 °C for 24 hours
What is the formula for % moisture for Proximate analysis-Moisture (water)?
- ANSWER (Weight of water loss/Weight of original sample) x 100
What is the formula for % dry matter for Proximate analysis-Moisture
(water)? - ANSWER DM= 100 - moisture
What is a source error for Proximate analysis-Moisture (water) - ANSWER
may overestimate moisture (underestimate DM ) from loss of volatile
compounds in
What are alternative methods for Proximate analysis-Moisture (water)? (2) -
ANSWER 1-drying under vacuum
2-freeze-drying
What basis assumes no water is present. This expression of nutrient
composition allows to accurately compare the nutrient composition of the
various feedstuffs. - ANSWER Dry Matter Basis
What basis represents feed as it would be fed to the animal, including water?
- ANSWER As-fed basis
What basis describes when feeds are allowed to air dry, most feeds
eventually equilibrate to ~ 90% dry matter (~ 10%moisture)? - ANSWER
Air-dry basis
What are the 2 rules for Dry-matter and As-fed Conversions? - ANSWER
1-The percentage of a nutrient on a dry matter basis will always be higher
, than it will be on an as fed basis
2-The amount of feed on a dry matter basis will always be lower than the
amount of feed on an as-fed basis
SEE pg 11 for equations
What is the importance of water or dry matter in Proximate analysis -
Moisture(water)? (4) - ANSWER 1-Proper moisture concentration for storage
2-Dry matter gives a basis to describe the quantity of feed consumed
3-Water is diluent of the other feed components
4-Moisture level affects the economic value of feedstuff
What 5 things does grinding an air dry sample produce for
chemical/proximate analysis? - ANSWER 1-Crude Fiber
2-Ether Extract
3- Crude Protein
4- Ash
5- other nutrient analysis
How do you prepare a sample for proximate analysis? (2) - ANSWER 1- Dry
55-60 °C)- only needed for wet/high moisture sample
2-Grind (1mm particle size) in Wiley mill
Complete Solution
The use of laboratory techniques to determine the concentration of
nutrients(and energy) in a feedstuff or diet - ANSWER Chemical evaluation
The use of animals, in some way, to measureutilization of nutrients from a
given feedstuffvor diet - ANSWER Biological evaluation
What is the first step of chemical evaluation? - ANSWER getting a
representative sample
What are the 3 selections of analytical methods in chemical evaluation? -
ANSWER 1-Proximate Analysis
2-Van Soest Detergent Fiber Analysis
3-Near-Infrared Spectroscopy (NIRS)
How many categories for particle compounds are there in proximate
analysis?
-list them - ANSWER 1-Water
2-Crude Protein
3-Ether Extract (crude fat)
4-Crude Fiber
5-Ash
6-Nitrogen Free Extract (NFE)
,Proximate analysis pitter - ANSWER
How long are samples heated at what temperature in proximate
Analysis-Moisture (water)? - ANSWER 105 °C for 24 hours
What is the formula for % moisture for Proximate analysis-Moisture (water)?
- ANSWER (Weight of water loss/Weight of original sample) x 100
What is the formula for % dry matter for Proximate analysis-Moisture
(water)? - ANSWER DM= 100 - moisture
What is a source error for Proximate analysis-Moisture (water) - ANSWER
may overestimate moisture (underestimate DM ) from loss of volatile
compounds in
What are alternative methods for Proximate analysis-Moisture (water)? (2) -
ANSWER 1-drying under vacuum
2-freeze-drying
What basis assumes no water is present. This expression of nutrient
composition allows to accurately compare the nutrient composition of the
various feedstuffs. - ANSWER Dry Matter Basis
What basis represents feed as it would be fed to the animal, including water?
- ANSWER As-fed basis
What basis describes when feeds are allowed to air dry, most feeds
eventually equilibrate to ~ 90% dry matter (~ 10%moisture)? - ANSWER
Air-dry basis
What are the 2 rules for Dry-matter and As-fed Conversions? - ANSWER
1-The percentage of a nutrient on a dry matter basis will always be higher
, than it will be on an as fed basis
2-The amount of feed on a dry matter basis will always be lower than the
amount of feed on an as-fed basis
SEE pg 11 for equations
What is the importance of water or dry matter in Proximate analysis -
Moisture(water)? (4) - ANSWER 1-Proper moisture concentration for storage
2-Dry matter gives a basis to describe the quantity of feed consumed
3-Water is diluent of the other feed components
4-Moisture level affects the economic value of feedstuff
What 5 things does grinding an air dry sample produce for
chemical/proximate analysis? - ANSWER 1-Crude Fiber
2-Ether Extract
3- Crude Protein
4- Ash
5- other nutrient analysis
How do you prepare a sample for proximate analysis? (2) - ANSWER 1- Dry
55-60 °C)- only needed for wet/high moisture sample
2-Grind (1mm particle size) in Wiley mill
