Chapter 1 Flashcards
5 reasons why nutrition is important
- Affects health
- production/performance
(rate of gain, milk production, race times, egg production - Body size
- 50-75% of total costs of raising livestock is feed costs
- employment (feed industry)
Who is the father of nutrition
Antoine Lavoisier
5 reasons we analyze feed in a lab for nutrient levels
- ration balancing
- compare results of 2 different seed varieties
- check for toxins/molds
- money value
- allocate certain feeds to certain classes of animals
what is the system/method for analyzing feeds
MECCAN
Weende Proximate Analysis Methods
Moisture content Ether exract (crude fat) Crude protein Crude fiber Ash Nitrogen Free extract
Test for Moisture
heat sample in forced air oven @105C for 48 hours
on farm -microwave(30 minutes) -Koster Tester (30 minutes) -electronic NIR (Near Infrared Reflectance)
Ether extract test
testing for all the fatty, oily ingredients in feed (lipids)
- most feeds have 3-6% of oil/fat in its dry matter
- Boil sample in liquid either for 4 hours
Crude Protein test
measures protein + non protein nitrogen
- Kjeldahl Test
- measures total % nitrogen in feed
- ***%Crude Protein=%Nitrogenx6.25
What percentage of nitrogen do most proteins contain?
16 percent
100 parts protein/16parts nitrogen=6.25
Crude Fiber Test
boil sample in weak acid, collect residue and boil it in weak base
-undissolved fibrous residue=%crude fiber
What is the relationship between crude fat and fiber to caloric value?
As crude fat% rises the greater the caloric value
As crude fiber% rises, the lower the caloric value
Ash Test
burn sample in muffle furnace @ 400-500C
2 Detergent Fiber Tests
- Acid Detergent Fiber
2. Neutral Detergent Fiber
2 parts of the cell thats hard to digest
cellulose
lignin
Nitrogen Free Extract
determined by mathematical calculation
What is the NIR test
very fast test, calibrated with wet chemistry (old methods)
cheaper per sample
