1. NUTRIENTS IN RELATION TO PROXIMATE ANALYSES
M. WAN ZAHARI
DVT UMK
4/21/2017

2. Elements and Atomic Weight
Name
Symbol
Atomic Wt
Carbon C 12
Magnesium Mg
243.3
Hydrogen H 1
Sodium Na 23
Oxygen O 16
Chlorine C1
35.
Phosphorus P 31
Cobalt Co 59
Potassium K 39
Copper Cu
63.5
Iodine I
127
Flurine F 19
Nitrogen N 14
Manganese Mn 55
Sulfur S 32
Zinc Zn
65.4
Calcium Ca 40
Molybdenum Mo 96
Iron Fe
55.8
Selenium Se 79

3. 1. Monosaccharides e.g glucose, fructose, galactose
Many different feed nutrients are currently recognized, and new ones are still being found. Those currently recognized are as follows:
A. Carbohydrate:
Contains C, H, and O, with H and O in the same proportion as in water. They consist largely of hexosans. These are made up of hexose or 6-carbon atom molecules.
1. Monosaccharides e.g glucose, fructose, galactose
2. Disaccharides e.g. sucrose, maltose
3. Polysaccharides e.g. starch, glycogen, cellulose, lignin
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4. Many different feed nutrients are currently recognized, and new ones are still being found. Those currently recognized are as follows:
Fats:
Contain C, H and O with more C and H in proportion to the O than with carbohydrates. Fats contain 2.25 times as much energy per kg as do carbohydrates.
1. Saturated fat e.g stearic, palmatic
2. Unsaturated fat e.g Oleic, linolenic, arachidonic
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5. Always contain C, H, O, N and sometimes Fe, P, and/or S.
Many different feed nutrients are currently recognized, and new ones are still being found. Those currently recognized are as follows:
C. Protein:
Always contain C, H, O, N and sometimes Fe, P, and/or S.
The only macronutrient which contains N
Feed proteins on the average contain 16% N.
Formed by various combinations of amino acids of which there are some 25+ to be found in proteins. Amino act as organic acids which carry the amino group (NH2).
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6. Continuation…..
D. Minerals: Of the 20 elements that function in animal nutrition, C, H, O & N are regarded as non- mineral elements
16 are mineral elements: 7 Macro minerals are Ca, P, K, Na, S, Cl & Mg and 9 Micro minerals are Fe, I, Cu, Co, F, Mn, Zn, Mo and Se.
E. Vitamins: Organic substances required by animals in very small amounts for regulating various body processes. They all contain C, H, O and several contain N & mineral elements
F. Water: Contain H & O. Water is found in all feed (ranging from 10% to 80%). Besides serving as nutrient and other important body functions, it is very important factor in feed processing & storage &feed value
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7. Continuation…..
D. Minerals:
Of the 20 elements that function in animal nutrition, C, H, O & N are regarded as non- mineral elements
16 are mineral elements: 7 Macro minerals are Ca, P, K, Na, S, Cl & Mg and 9 Micro minerals are Fe, I, Cu, Co, F, Mn, Zn, Mo and Se.
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8. They all contain C, H, O and several contain N & mineral elements
Continuation…..
E. Vitamins:
Organic substances required by animals in very small amounts for regulating various body processes.
They all contain C, H, O and several contain N & mineral elements
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9. Water is found in all feed (ranging from 10% to 80%).
Continuation…..
F. Water:
Contain H & O.
Water is found in all feed (ranging from 10% to 80%).
Besides serving as nutrient and other important body functions, it is very important factor in feed processing & storage &feed value
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10. SUMMARY OF THE VARIOUS FUNCTIONS WHICH THE DIFFERENT NUTRIENTS MAY SERVE
BASIC FUNCTION
ACCESSORY FUNCTION
As a Structural Material for Body Building and Maintenance
As Energy for Heat Production, Work, and Fat Deposition
As or for the Formation of a Body Regulator
As a Source of Nutrients for Milk (or Egg Production)
Protein
Yes
Certain
Amino acids
Carbohydrates
Only as fat formed from carbohydrates enters into makeup of cellular growth
Fats
Only as fat enters into makeup of cellular growth
Fatty acids
Minerals No
Vitamins
Water
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11. Proximate Analysis of Feedstuffs
A system for approximating the value of a feed or material for feeding purposes, without actually using the feed in feeding trial, was developed at the Weende Experiment Station in Germany over 100 years ago.
It based on the separation of feed components into groups or fractions in accordance with their feeding value.
The various fractions are:
Water Crude fiber
Crude protein Nitrogen-free extract
Crude fat or ether extract Mineral matter or ash
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12. Proximate Analysis of Feedstuffs
Following proper procedures in obtaining and preparing a sample is essential for an accurate analysis on given lot of feed.
Procedures to determine the various fractions:
Water- oven dry : Loss of wt during drying  100 = % water
Wt of sample after drying
Wt of sample after drying  100 = % DM
Wt of sample before drying
100 - %DM = water
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13. 2. Crude protein (CP) Kjeldahl methods-determine the amount of ammonia nitrogen (N) 3. Crude fat (EE) Includes all of that portion of a feed soluble in water. Crude fat is commonly referred to as ether extract. Extract the sample with ether in a Soxhlet extractor .
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14. 4. Crude fiber (CF):
This fraction was designed to include those materials in a feed which are low digestibility. Included hare are cellulose, certain hemicelluloses, and some of the lignin, if present. Some of the lignin, however, may be included in the nitrogen-free extract.
- dry sample, extract sample with ether, boil sample with dilute sulfuric acid, filter, boil in dilute sodium hydroxide then filter, dry the residue and weigh, ash the sample
Wt of CF  100 = % CF
Wt of original sample

15. 5. Mineral matter or ash:
Ash in a furnace (600 °C)
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16. 6. Nitrogen-free extract: (NFE)
Commonly referred to as NFE. Includes mostly sugars and starches, and some of the more soluble hemicelluloses, and some of the more soluble lignin.
Since this fraction was designed to include the more digestible carbohydrates, any lignin which may come out here will to distort the meaningfulness of the NFE figure as lignin is essentially indigestible.
NFE is determined by difference-that is, all those fraction discussed above are added together and subtracted from 100.
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17. As follows: % water % crude protein % crude fat % crude fiber % mineral matter – Total = % NFE
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18. 7. Expressing compositions:
A. In percent (%). This simply say that a feed contains so many parts (grams, milligrams, micrograms, etc.) of a particular feed component per 100 parts of the overall feed.
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19. B. In parts per million (ppm)
This simply says that a feed contains so many parts (g, mg, mcg, etc.) of a particular feed component per1,000,000 parts of the overall feed.
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20. C. In mg per kilograms (mg/kg).
This says a feed contains so many mg of some component per kilogram of the overall feed. Since a kilogram is equal to 1,000,000 mg, then “mg per kilogram” is the same “mg per million mg” or “parts per million”.
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21. The composition of feeds may be expressed on any one or more of three dry matter bases.
A. As fed: Sometimes referred to as wet or fresh basis. On this basis dry matter of different feeds may range from 0% to 100%.
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22. Most feeds, but not all, are fed in an air-dry state.
B. Air-dry:
May be actual or an “assumed dry matter content” basis. The latter is usually 90%.
This basis is useful for comparing the composition of feeds having different moisture content.
Most feeds, but not all, are fed in an air-dry state.
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23. Based on a moisture-free or 100% DM state.
C. Oven-dry:
Based on a moisture-free or 100% DM state.
Also useful for comparing feeds of different moisture contents.
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24. Why Test Feeds?
Nutrient concentration can vary considerably in feeds, especially forages
Used feed tests to target specific feeds to different livestock
Feed test can help establish the RM value of a feed
Use feed test to help determine what feedstuffs to buy for feed processing activities
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25. What causes nutrient concentration to vary?
Plant species and variety-protein, starch, fiber and toxins varies among varieties
Maturity-as forage plants mature, fiber concentration increases, concentration of DE & NE
Leafiness-leaves contain more CP & DE, harvest & storage conditions that save leaves result more CP and energy
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26. What feeds should be analyzed?
Analyze all feedstuffs that influence ration cost or animal performance. Important when potential differences between estimated nutrient composition and actual composition are great
Forages: nutrient composition varies greatly
Feed grains: seasonal & geographical differences-may influence future purchases
By-products: vary considerably in nutrient & moisture content
Always test non-traditional feedstuffs
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27. What causes nutrient concentration to vary?
Harvest-good management techniques ↑ nutritive values
Storage-moisture content within specific range
Environment-temperature, sunlight, soil moisture & fertility, diseases, weeds, insects
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28. Methods of Feed Testing
Physical: sight, smell, touch…., stage of maturity, foreign materials, best, color-provide limited information
Chemical-reliable & accurate predictions of animal performance
Near infrared reflectance (NIR) spectroscopy
In vivo and in vitro
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29. What analyses should be made?
Nutrients of primary concern: Ruminant (CP, DE or TDN, Ca, P), Monogastric (CP, amino acids, ME, CF, Ca, P)
Always compare cost of analysis to cost of supplement
Analysis for moisture, protein & energy are most important
Sampling is the key to accurate feed analysis
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