Term
| parts of the plant cell that are completely digestible |
|
Definition
the cell contents:
-sugars
-starches
-fat
-protein
-NPN
-pectins |
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Term
| parts of the plant cell that are partly or completely indigestible |
|
Definition
cell wall:
-cell wall
-hemicellulose
-lignin
-cellulose |
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Term
| this determines the nutritive value of a plant |
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Definition
| The parts of the plant that are digestible determine the nutritive value of the plant |
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Term
| spacing of bundle sheaths in warm season grasses |
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Definition
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Term
| anatomy of warm season grass at various scales |
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Definition
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|
Term
| grasses with which type of p'synth have more energy? |
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Definition
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|
Term
| depiction of the types of cell walls that can be found in forage plants |
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Definition
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|
Term
| which cell wall is more important and why? |
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Definition
| The secondary cell wall is more important because it makes the frame in general. |
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Term
| why you don't wanna go beyond a certain age in forage plants |
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Definition
| because if you go beyond it, there’s too much accumulation of lignin |
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Term
| microscopic view of cellulose in a newly divided cell wall |
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Definition
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|
Term
| microscopic view of secondary cell wall encasing primary cell wall |
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Definition
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|
Term
| depiction of the general anatomy of a plant cell wall |
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Definition
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Term
which part of the plant cell wall is number 1?
[image] |
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Definition
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|
Term
which part of the plant cell wall is number 2?
[image] |
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Definition
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|
Term
which part of the plant cell wall is number 3?
[image] |
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Definition
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|
Term
which part of the plant cell wall is number 4?
[image] |
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Definition
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|
Term
which part of the plant cell wall is number 5?
[image] |
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Definition
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|
Term
| depiction of the composition of cellulose |
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Definition
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|
Term
which part of cellulose is number 1?
[image] |
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Definition
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|
Term
which part of cellulose is number 2?
[image] |
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Definition
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|
Term
which part of cellulose is number 3?
[image] |
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Definition
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|
Term
which part of cellulose is number 4?
[image] |
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Definition
| chains of cellulose molecules |
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Term
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Definition
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|
Term
| structure of hemicellulose |
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Definition
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|
Term
|
Definition
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|
Term
|
Definition
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|
Term
| starch and cellulose are made of glucose, but cellulose is harder to digest. why is that? |
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Definition
| because of the way it’s packed; chair conformation |
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|
Term
| how the number of side chains on hemicellulose affects digestibility |
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Definition
| The fewer the side chains, the more digestible the fiber. |
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|
Term
| why the hemicellulose is more digestible in younger plants than in older plants |
|
Definition
| fewer side chains in younger plants |
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|
Term
|
Definition
| Phenolic compound in plant cell walls, esp. in older tissue |
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|
Term
| why lignin is hard to digest |
|
Definition
| because it has no repeating structure |
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|
Term
| Trees have their strength because of... |
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Definition
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|
Term
| how lignin ca be digested |
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Definition
| can be digested with acid, but the chunks are still there |
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Term
| Forage “Quality” includes... |
|
Definition
1) nutritive value
2) Physical attributes of forage that regulate intake
3) “antiquality” compounds that limit intake (flavors, toxins, tannins) – these are aspects related to palatability. |
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|
Term
| nutritive value includes... |
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Definition
-Energy Value (from carbohydrates (starch, fructans, cellulose and other cell wall components))
-Crude Protein
-Minerals |
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|
Term
| how to calculate feed value |
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Definition
| Feed value = nutritive value * physical aspects of the forage |
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|
Term
| Some antiquality elements in forages |
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Definition
| tall fescue endophytes, toxins, and such |
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|
Term
|
Definition
| they can be a little bit good in terms of bloating |
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|
Term
| how to calculate dry matter digestibility |
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Definition
| (kg dry matter intake - kg fecal dry matter)/(kg dry matter intake) |
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Term
| how dry matter digestibility is usually measured |
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Definition
| Usually measured as in vitro dry matter digestibility using rumen fluid in a laboratory digestion protocol. |
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Term
| the Van Soest fiber analysis system |
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Definition
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|
Term
| what the detergent does in the Van Soest fiber analysis system |
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Definition
| The detergent breaks apart the cell wall because the content of the cell can’t be accessed unless you digest the cell wall |
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Term
|
Definition
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|
Term
|
Definition
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Term
| proximate analysis summary |
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Definition
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|
Term
| what the proximate analysis summary is used for |
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Definition
| it is used a lot, especially for concentrates |
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|
Term
| the proximate analysis summary reveals... |
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Definition
| the dry matter and moisture |
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|
Term
| why the number 6.25 is used for proteins |
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Definition
| because proteins have about 6.25% N |
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|
Term
| what happens to the organic stuff when you burn organic matter? |
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Definition
| When you burn organic matter, the organic stuff goes away, leaving behind minerals |
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|
Term
| the part of the proximate analysis summary where you got fats |
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Definition
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|
Term
| Proximate vs. Van Soest Analysis |
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Definition
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|
Term
| why cellulose and hemicellulose can be partly digested |
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Definition
| Cellulose and hemicellulose are partly digested, thanks to microbes and such |
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Term
| why some of the digestible stuff goes to the feces |
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Definition
| because of microbial cells (MC) and endogenous secretions (ES) |
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Term
| why alfalfa is higher in protein than Timothy grass |
|
Definition
| because Alfalfa is a legume |
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|
Term
|
Definition
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|
Term
| diagram of where energy from food can be lost |
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Definition
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|
Term
| Some energy that could be used in fermentation |
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Definition
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|
Term
| an energy related reason animals are sometimes given antibiotics |
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Definition
| Animals are sometimes given antibiotics to minimize energy loss from fermentation |
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|
Term
| how much digestible energy can be lost? |
|
Definition
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|
Term
|
Definition
| the stage where the inflourescence moves towards elongation, something like that |
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|
Term
| amount of fiber in a forage vs. fillingness to the animal |
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Definition
| The more fiber in the forage, the more filling it is to the animal |
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Term
| amount of fiber vs. amount of energy |
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Definition
| When the amount of fiber goes up, the amount of energy goes down |
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|
Term
| characteristics of forages that regulate intake by the animal |
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Definition
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|
Term
| how to calculate Estimated Digestible Dry Matter (DDM) |
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Definition
| Estimated Digestible Dry Matter = 88.9 – [0.779 x ADF(%)] |
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|
Term
| how to calculate Estimated Dry Matter Intake (DMI) |
|
Definition
| Estimated Dry Matter Intake = 120 / NDF (%) |
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|
Term
| how to calculate Relative Feed Value (RFV) |
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Definition
| Relative Feed Value (RFV) = (DDM x DMI) / 1.29 |
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|
Term
| ADF is used to measure... |
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Definition
|
|
Term
| NDF is used to measure... |
|
Definition
|
|
Term
|
Definition
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|
Term
| this decreases the digestibility of alfalfa |
|
Definition
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|
Term
| composition of the whole alfalfa plant |
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Definition
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|
Term
| composition of alfalfa leaves |
|
Definition
18-28% NDF
12-20% ADF
22-35% CP |
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|
Term
| composition of alfalfa stems |
|
Definition
35-70% NDF
30-55% ADF
10-20% CP |
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|
Term
| digestibility of the contents of alfalfa cells |
|
Definition
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|
Term
| digestibility of the contents of alfalfa cell wall |
|
Definition
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|
Term
| the 3 most important polysacs in terms of forage quality |
|
Definition
-cellulose
-hemicellulose
-lignin |
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|
Term
| one polysac you don't want in forages if you have a choice |
|
Definition
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|
Term
| the impact of maturity on cell wall c'tration |
|
Definition
| the, more mature, the more lignin in the cell walls |
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|
Term
|
Definition
| when the plant starts shifting to reproduction |
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|
Term
| why fiber increases as the plant matures |
|
Definition
| because the amount of growth in the stems is higher |
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|
Term
| why the protein content goes down as the plant matures |
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Definition
| because all the plant’s focus is on the flowers and influorescence |
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|
Term
| the amount of cell walls vs. maturity |
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Definition
| As the plant matures, the amount of cell walls increases |
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|
Term
| Relative feed value (RFV) |
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Definition
| An index for ranking grass and legume forages based on combining digestibility and intake potential. Calculated from ADF and NDF. The higher the RFV, the better the quality. It is used to compare varieties, match hay/silage inventories to animals, and to market hay. |
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|
Term
| RFV is calculated from... |
|
Definition
|
|
Term
|
Definition
| the higher the RFV, the better the quality |
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|
Term
|
Definition
| It is used to compare varieties, match hay/silage inventories to animals, and to market hay |
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Term
| why tropical perennial grasses are lower in quality |
|
Definition
| because of the distribution of bundle sheath cells |
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|
Term
| why is orchardgrass more digestible than Bermudagrass? |
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Definition
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|
Term
| some things that factor into intake of forages by the animal |
|
Definition
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|
Term
| some things about management that factor into intake of a forage by an animal |
|
Definition
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|
Term
| some things about feed that factor into intake of a forage by an animal |
|
Definition
-palatability attributes
-physical properties
-nutrient availability |
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|
Term
| some things about the animal that factor into intake of a forage by an animal |
|
Definition
-capacity
-appetite (energy demand) |
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|
Term
| why feed is necessary for animals |
|
Definition
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|
Term
| the limitations of using a metabolism crate to measure metabolism ofan animal |
|
Definition
-The metabolism period requires a minimum of 7 days faecal / urine collection,
-May need to be varied for specific purposes but should not exceed 10 days for cattle over 400 kg confined to crates.
-Feed intake is generally determined 24 hours prior to the collection period given the lag between feed eaten, and urine / faeces excreted. Hav e to start here because the forage takes about 24 hours to go thru the system.
-The total length of time an animal is confined to the metabolism crate is generally no longer than 14 days, |
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|
Term
| why a metabolism crate is not a good way to measure metabolism of an animal |
|
Definition
| This affects results because the animal is used to roaming free and the confinement stresses them out, affecting the metabolism |
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|
Term
| Limitations to Digestion Studies for Pastures |
|
Definition
-Forage always changing – can’t collect adequate supply of fresh forage at a constant stage of development
-Digestion studies expensive and time consuming
-Hard to compare many different species or varieties with different sampling dates, replications, etc. |
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|
Term
| why the forage is considered to be always changing |
|
Definition
| because it doesn't stay at a constant stage of development |
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|
Term
| a means of wet chemistry for digestion studies |
|
Definition
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|
Term
| how the Van Soest Analysis works |
|
Definition
1: Grind sample to 1-mm size in a Wiley Mill (standard) (day 1)
2: Perform reflux reactions (ADF, NDF) (days 2, day 3)
3: Perform 72% acid digestion (ADL) (day 4); this digests the cellulose and leaves behind lignin
4: Ash sample (day 5) contains minerals
5: Calculate energy values from fiber content |
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|
Term
| disadvantages of the Van Soest Analysis |
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Definition
| This is still a slow, labor intensive method – not useful for many samples, or for routine use in testing laboratories. |
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|
Term
| the light frequency used by Near Infrared Reflectance Spectroscopy (NIRS) |
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Definition
| Infrared spectrum = ~780 – 2500 nm, just above visible spectrum |
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|
Term
| why the Near Infrared Reflectance Spectroscopy (NIRS) can be used to analyze forages |
|
Definition
| because different constituents in a forage consistently absorb or reflect different wavelengths |
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|
Term
| what the Near Infrared Reflectance Spectroscopy (NIRS) method of analyzing forages analyzes for |
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Definition
| relationships between particular wavelengths and certain components, such as NDF |
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|
Term
| methodology of Near Infrared Reflectance Spectroscopy (NIRS) in brief |
|
Definition
1 – Evaluate reflectance of many samples
2 – Calibrate the reflectance based on wet chemistry
3 – Predict the values of samples not run with wet chemistry |
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|
Term
| even with Near Infrared Reflectance Spectroscopy (NIRS), you still gotta do the wet chemistry from time to time. why is that? |
|
Definition
| to determine the parameters; most of the time, it is species specific |
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|
Term
|
Definition
-Grind sample to 1-mm size in a Wiley Mill (standard) (day 1)
-Scan sample (1 minute each)
-Select* a subset of scanned samples to run through wet chemical analysis
-Calibrate* spectral characteristics using wet chemical results
-Predict remaining samples without wet chemistry
*Can be skipped if a calibration equation has already been developed. |
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|
Term
| how to estimate Net energy of lactation (Mcal/lb) (NEL) |
|
Definition
| NEL = 1.50 - (ADF% x 0.0267) |
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|
Term
| Problems with Predictions when it comes to forages |
|
Definition
Assume ADF has constant relationship to digestibility – not true in reality
Better to use a measure of digestible fiber than ADF |
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|
Term
| Relative forage quality (RFQ) |
|
Definition
| An index for ranking grass and legume forages based on DN and intake potential. Calculated from NDF, CP, EE, NDFD, ADF, and NFC. It matches animal performance better than RFV across a wide range of forages. |
|
|
Term
| advantage of RFQ over RFV |
|
Definition
| It matches animal performance better than RFV across a wide range of forages. |
|
|
Term
| the analysis that gives you more details |
|
Definition
|
|
Term
| the analysis that gives you a better indication of performance |
|
Definition
|
|
Term
| advantages of proximate analysis |
|
Definition
| Proximate analysis gives you more details and a better indication of performance |
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|
Term
| The toxic range for nitrates |
|
Definition
|
|
Term
|
Definition
| all the parameters and such |
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|
Term
| why dry matter yield peaks in March or spring |
|
Definition
| because of the cool season forages |
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|
Term
| when warm season grasses have their peak |
|
Definition
|
|
Term
| maximum yield corresponds with... |
|
Definition
|
|
Term
| Older forage tends to have (more or less) energy available |
|
Definition
|
|
Term
|
Definition
|
|
Term
| when you need to supplement feed |
|
Definition
| at the point of lowest energy |
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