Nutrients Flashcards
What are organic compounds in feed?
compound containing carbon usually bonded to hydrogen
(ie. methane, ethanol, carbohydrates, lipids)
What are inorganic compounds in feeds?
compounds without carbon
(ie. CO2, salt, minerals/elements)
What are the main components of feed desribed by proximate analysis?
- Moisture
- Ash
- Crude protein
- NDF and ADF
- Non-fiber carbohydrate
How much of an animals mass is water?
71-73%
What is the difference between as-fed and dry matter?
As-fed = feed nutrient content with water included
DM = feed nutrient content with water removed
Why is feed nutrient content reported on a DM basis?
better comparison between feeds
What is ash a measure of?
estimate of inorganic mineals
How is ash determined?
heat feed at 600C for 6hrs
How is organic matter determined?
Organic matter = 100-ash
How much nitrogen is in crude protein?
16%
How is crude protein determined?
Kjeldahl method or total combustion method
Kjedahl method involves sulfuric acid, NaOH, and dilute base
Saturated vs unsaturated fat?
Saturated: no double bonds
Unsaturated: double bonds
Fats vs oils
Fats: solid, contain saturated FA
Oils: liquid, contain unsaturated FA
How is crude fat determine?
Ether extract
What are structural carbohydrates and what are 2 examples?
Responsible for structure of plant, in cell walls
Cellulose
Hemicellulose
What are non-structural carbohydrates and what are 3 examples?
Cell content, store energy of cells
Sugar, Starch, Pectin
What is NDF and how is it determined?
measures fiber content (lignin, cellulose, hemicellulose)
soak in neutral detergent
What is ADF and how is it determined?
Measures least digestible parts of plant (lignin, cellulose)
Soak in acid detergent
What is peNDF and how is it determined?
physically effective fiber, has to be 4 mm in length using a particle separator
Why is peNDF important?
scratch factor for pili
What is the most energy dense component of feed? Least energy dense?
Fatty acids - most
Carbohydrates - least
What is NIR? What are its strengths and weaknesses?
Near infrared spectroscopy, measures organic compounds
Less accurate
Quick, cheap
What are the major resources for animal requirements?
National Requirements
